School of hard Knox

[tomhall]

Tom T. Hall in Minnesota here, I am just back from Knox, IN. I spent 8 days with Duane Hunn and another student, Bob Mc Guire. After building for 2 years, I had great expectations. We got a lot done; much theory, a lot of adjusting, prop pitching & balancing, making 4 cylinders fire instead of 2. What we did not do is FLY ! Because Duanes RAF could not develop full power, we did 3 crow hops. I believe we did make the most of an unfortunate situation, but it does remind us of the weak link in most gyro instruction: we are dependent on a few single instructors who have one training aircraft. The student needs the instructor and his bird to be both present and healthy ! There are several gyros at Knox and last Saturday an older RAF flew in ( Phil Hecht ) and a Sycamore visited as well. Met some good guys & had perfect weather. I met with the FAA D.A.R. and passed his inspection ! As Duane suggested, we need something like a " Gyro Camp" several times a year where 2 or more instructors are present along with a D.A.R. and an examiner. It's not perfect yet, but it must be better !!

[barnstorm2]

Tom, I think a 'Gyro Camp' is a great idea. Congratulations on passing the inspection!

[Rotornut]

Tom, Way to go! But no Flying does stink! Hope it works out better in the Near Future. Keep on Plucking Away. MJ :)

[landman]

Say Tom, are you related to the famous (my hero) Tom T Hall the singer.

Martin Oliver

[tomhall]

Martin, I am not that guy, but for forty bucks I'll sing you a ballad !

[Rotornut]

lol MJ :)

[landman]

bucksbucksbucksbucksbucksbucksbucksbucksbucksbucks bucksbucksbucksbucksbucksbucksbucksbucksbucksbucks bucksbucksbucksbucksbucksbucksbucksbucksbucksbucks bucksbucksbucksbucksbucksbucksbucksbucksbucksbucks

Music maestro please. :D

Martin Oliver

[Udi]

Tom - congratulations for getting your bird certified! While you were there, did you get Duane to test fly your RAF? Do you have some pictures of your gyro?

By the way - at their facility in AZ, AAI have multiple (some of the best) flight instructors and multiple gyros for training. It may be best for you if you can get training in your own machine, though.

Udi

[Aussie_Paul]

The student needs the instructor and his bird to be both present and healthy !

You are so right Tom. I have many students who come from far and wide Nationally and Internationally to train with me. I always try to have a spare of everything. I like to be able to be back operational within 24 hours. I have even cross hired a machine for a couple of days once.

When students make the quite expensive decision to come and learn to fly with me I do my damndest not to let them down.

Geez, Internationally we need more "good quality instructors" availible on a continual training basis, not just as weekend part time instructors. I reckon that alone is the major detterant to the growth of our sport.

Aussie Paul. :)

[tomhall]

Hi guys, I really appreciate the support I get here on the forum. I don't feel so alone ! I will post some photos soon and as soon as I tune my guitar I guess I'll be singin' something about watermelon wine. Thanks again. Tom

[Gyropilot007]

Guys:

I'm Bob McGure, the other student that was training at Knox with Duane Hunn at the time that Tom Hall was there.

My experience was similar althought my circumstances were quite different. I live in Valparaiso, Indiana and work in Hobart, Indiana. Both places are no more than 40 minutes from the Starke County Airport in Knox. Tom, on the other hand, livies in Minnesota and had a significantly longer drive. Tom also took some vacation time to make the trip.

I arranged my work schedule so that worked in the mornings and then drove out to the airport in the afternoons. With this arrangement Tom was the first shift in the morning, we overlapped a bit in the afternoon and then I stayed in the evening.

Both Tom and I were able to do the "crow hopping" on Monday of that week. During that testing Duane determined that his engine was not developing full RPMs. After a lot of testing Duane decided to install a different engine.

Duane, through his many connections, was able to locate an engine. Tom and Duane worked for several days to installed and check out the engine. Unfortunately, Duane's aircraft was not ready to fly before Tom had to leave.

The time spend with Duane was certainly worthwhile. Duane gave us a lot of good information regarding the aerodynamics of gyroplanes and the principles of gyro flight. We were also able to work on our own gyros doing a hang test, setting up the control systems and balancing the props.

Tom left on Monday morning, October 11th. That afternoon Duane and I finished working on Duane's machine and Duane took it for a test flight. Everything checked out OK.

As a side note I will tell you that I had a little accident with my machine. After balancing the prop I was going to taxi my machine to the hanger. When I started up my engine the throttle stuck in a high RPM position. My gyro started moving fast toward a hanger. I worked the throttle several times but the engine did not slow down. I stepped hard on the brakes and fiinally turned off the engine. I slowed down but was unable to avoid hitting the hanger. Fortunately there was only minor damage to the gyro and the damage is only cosmetic. It is still perfectly flyable.

Anyway, during the last few days I have had my first two gyro flying lessons and I'm really enjoyingi it. I received my private pilot for fixed wing when I was 18 and I'm 50 now. I can tell you all I'm really looking forward to flying gyroplanes.

Duane is planning to be at Knox until October 30th and I'll be there everyday to further my training. I think Duane is a wonderful instructor and I'm amazed at his knowledge of gyroplanes.

I'd also like to thank Jim Logan for helping me locate a source for a replacement drive belt. Jim was a big help.

When Tom was here I had the pleasure of meeting his wife and the other members of his family, his two dogs, Redbud and Ginger. One night after training, Tom, Tom's wife Leslie, my wife Kathy and I had a lovely dinner at Strombow's restaurant in Valparaiso. It was an evening of good food and good conversation. I look forward to continuing my training and to seeing Tom again in the future.

Bob McGuire

[tomhall]

Here are photos of my bird from the "School of Hard Knox". Enjoy :)

[tomhall]

For clarification : I am Orange, Bob McGuire is " Star Trek " and Duane is Yellow ! Tom T. Hall

[Gyropilot007]

Tom's dogs are named Redbud and PEPPER. Sorry for the error.

Bob

[Alan Coats]

You guys hurry up and send Duane back to Oklahoma - I am waiting for him to return so I can continue my training. I agree, Duane has many years of gyro experience, in all kinds of machines, and seems to love sharing his knowledge.

I live about 2 1/2 hours away from Duane's hangar. My biggest problem is saving up money for the lessons. Sure would like to be able to spend a week at a time learning - I'm sure it would speed up the process.

What are you guys going to have to do to continue your training?

Alan

[Rotornut]

Nice Birds! Good Luck and I agree, Duanne is a Good Instructor. MJ :)

[Aussie_Paul]

I flew with Jim Logan on a Raf arranged flight check, and flew with Duane and Lisa for fun. I think that Duane and Lisa felt sorry for my brother Lin and I sitting there watching 'cause we did not have a gyro. Daune took Lin for a flight as well. That was really appreciated.

Jim is more the pilot who came up through the GA to professional heli pilot, and makes a very good check pilot.
Daune came up through the gyro school of hard knocks, mac attacks engine failures etc. I am a cross between both of these friendly gentleman. I like to give credit where credit is due.

Unfortunately these guys don 't love me very much any more due to the Raf stability/instability issues that we fought about, but I enjoyed their company at Bensen days 1999 when I was very much in the Raf camp, and had not been to NZ and flown with Rob Sanders in his basic stab Raf.

The attached pic of Jim Logans gyro was taken by Lin from Duanes gyro.

Aussie Paul. :)

[bones]

Paul i agree with you, from where i am the nearest instructor that i have found is Dave Stubberfield and he is 8-9 hrs drive from here, and i know of at least three people who have been put off by the driving distance, unlike me who just decided last christmas to jump in the car and drive 27hrs just to get on the drink for two days with a few mates :)

[StanFoster]

Paul: I personally met Jim Logan at Mentone this year. I was very impressed with his gyrocopter skills...and very much appreciated the time he spent to chat with me. He is a very humble person and its too bad such a nice person has had to receive so much flack for his type of flying.

Stan

[Chuck_Ellsworth]

Well I'm back from my summer flying contract in Europe and surfing through these posts.

I know I will not be popular with some here, but looking at the stabless RAF's makes me feel like I have sort of gone back in a time warp.

It is very disturbing to me to see that after all these years and all the needless deaths we still have a small group that refuse to add a safety device to their aircraft.

Truly disturbing from my perspective.

Chuck E.

[mcbirdman]

His "Type" ? C'mon. Do you mean that he is the type who doesn't think it matters? The type that has been in the minority for how many years? The type who does'nt agree with what stable is or agree with the new standards?..... Oh, I guess I know by looking at the machine he is training students in.......

Sorry but being nice don't change facts..... I too thought/think he is nice. Wrong though, but nice. jtm

[pwendell]

Chuck,

Welcome back.

There are still LOTS of motorcyclists that ride without helmets, several folks on this board with stabbed/clt gyros among them, even though everyone knows helmets are much safer. There's absolutely nothing to be done about it. People will make poor decisions. Period.

I have no problem with this. But, if these people claim their way is safer or better, or when they propagandize the uninformed that their way is better and the other guys are 'safety Nazis' or 'left wing wackos' or simply 'wimps', then I have a big problem.

I don't know Jim Logan. He probably is a very nice guy and a very accomplished gyro pilot and instructor. I have no problem at all with his enjoying the heck out of his stabless RAF. I have a big problem with his teaching in that same aircraft. I don't know how he will live with himself if even one his students dies unnecessarily in a stabless and/or HTL gyro. As an individual he can do what he likes. As a professional he is obligated to provide his students with the best training and knowledge possible based on OBJECTIVE and VERIFIABLE data.

It really ticks me off when I read in aviation mags, like 'Kitplanes', that there is a 'debate' in the gyro community over stabs and CLT. As far as I know there is now only one company, RAF, who does not embrace stabs and (near) CLT as essential to gyroplane stability. They should be shunned and marginalized until no one listens to them anymore.

Again, I have no problem with any individual who chooses to fly a stabless RAF. That is their concern. If, however, they claim their stabless/HTL machines are safer, have higher performance, or that stabs and CLT are unneccesary to a stable gyro, then they have stepped over the line and should be vociferousely and intelligently challenged at every opportunity.

I think most people on this forum probably agree with me.

[Chuck_Ellsworth]

Pwendell :

Thank you for your thoughtful comments.

Many years ago I almost became a Gyro Flight Instructor, however circumstances have to this point in time forced me to put that idea on hold.

I do however keep in touch with all my many friends that I have come to know through the Gyro forums.

Also I am still actively earning a living as an advanced flight instructor in large airplanes and it really makes me sad to see that there are a small group of people who are making a mockery of my profession by teaching bogus and dangerous misstruths about stability in simple flying machines such as gyroplanes.

I am against Government intervention and more regulation however sooner or later these charletons will be the cause of Government intervention into the gyroplane community.

I long for the day when I and others do not have to crush the enthusiasm of new commers to gyroplane flying by having to convince them that they are being lied to and decieved by this morally challenged fringe group affiliated with RAF who should be stripped of their designation of CFI.

I know these are strong words and will offend many, but I stand by my opinion.

Chuck E.

[pwendell]

I am against Government intervention and more regulation however sooner or later these charletons will be the cause of Government intervention into the gyroplane community.

Chuck E.

Chuck,

I think ultimately we have to police ourselves. If the RAF boys are the only ones out there saying stabs don't matter and the relationship between propeller thrust line and VCoG doesn't matter, and if the rest of us work hard to improve gyro training and lower our fatalities -- which seems to be happening--the FAA will have to give RAF a pretty close look.

I really hope you do become a gyro CFI and apply the same standards to gyro students as you do with your advanced FW students. As gyro pilots, we need to hold ourselves, and each other, to the highest possible standards. Because we are few and strange, our behavior needs to be beyond reproach.

[birdy]

Well said Peter and Chuck. :)
I agree with everything you said.
Only coz you said "performance" not "manouverability." Peter. ;) :D

BTW chuck,how's the airobatics cum'n along?

[Aussie_Paul]

Bones, unfortunately there is only one way to get into gyros and that is to "take a couple of weeks and go to a full time instructor". It is annoying and difficult but it is very successful. Better still if they can take their own machine and be very proficient in their own machine before they leave. Otherwise it takes forever, people become despondent, we lose them to the industry and more importantly they do not get to enjoy what we love. :(

I have a policy that if a student has no previous flying experience, I will not guarantee a certificate in 2 or even 3 weeks. The absorption rate is too high. :eek: I like these people to came for a week and gain most of the skills and info they need to build or buy a gyro. When they have their machine ready, I like them to come back again and have me check and test fly their machine, then solo them in it after they reach the standard. This can usually be achieved in a couple of weeks if those weeks are a couple of months apart. :cool:

If the student has previous flying experience and brings their pride and joy gyro with them I can usually guarantee success in a couple of weeks. :cool:

Aussie Paul. :)

[KenSandyEggo]

Well said, guys. I couldn't have said it better myself......well, maybe I could have with a little effort. Naaaaaaah. You guys said it well. I wonder who will be the first one to accuse you of being "bashers?"

I wish I would have saved the posts where Logan came on here a few years ago and tried to convince us that there is nothing dangerous about doing a full power climb and pushing the stick forward without reducing power at the top in a stabless RAF. He tried to convince us by plagiarizing and rearranging material from the FAA Rotorcraft Handbook, quoting selected bits from the heli section that pertained only to helis, and trying to make it appear that it was from the gyro section. He was caught red-handed and that was the last we ever heard from him here.

If he had gone unchallenged, I wonder how many corpses there would be from those gullible enough to have believed his lies.

[Vance]

I had an hour leson with Mr Logan at Mentone and it was very interesting. his machine is very well matained and nicely detailed. I found myself pitching slowly up and down for about the first 45 minuets but then I was able to stay with the machine. It was my inputs because when I left his machine alone it would stabilize. Unsolicited he told me that I might be more comfortable with a horizantal stabilizer. We were flying in 15 mph gusting wind and I did not feel comfortable trying a cross wind landing at the big airport. Aparantly he was not comfortable with my flying skills because he kept coming on the controls unanounced. I am more comfortable in either an AAI modified RAF or the Sparrow Hawk. I felt he was a very carefull and qualified instructor. He showed me an interesting way to come around the trees at the Mentone airport. I came away feeling that I would not want to fly an RAF without a horizantal stablizer. His ship had the stabilator on it and it seemed to change the way the stick felt but since I hadn't flown an RAF without one I am not sure just what it did. Thank you, Vance

[KenSandyEggo]

If you were initially pitching up and down, with him having to take over the stick from you, then I can assure you that it doesn't do anything.

[cgmg]

Ken,

I agree with your statement.

Five or six years ago, when my wife and I were newbies to the sport, we drove over to Indiana to take some lessons from Duane. We, too, were enthralled with the RAF and its looks. It was a warm and sunny September day, with plenty of thermal activity. Duane had to take control and "settle things down" a number of times during my flights with him. Not knowing any better, I just thought that was the way gyros flew.

Duane moved out of Indiana before we could resume our lessons with him, and other than a flight the next year at Fondulac, we haven't been in an RAF since. To Duane's credit, he is an individual who loves flying gyros. He laughed the entire lesson with us, he was having so much fun.

Fortunately for us, we ended up with an instructor who told me that, with my inability to catch pitch diversions in his Tandem Air Command trainer early enough, that we should invest in a centerline thrust machine. His reasoning was that a centerline thrust machine, with an adequate horizontal stabilizer, would be the safest machine we could fly.

That's what we fly now, a single-place centerline thrust Air Command, with the extended keel, and a horizontal stabilizer. In just over 100 hours of flying our machine, I've not had to reduce the throttle, or adjust the stick, to control a pitch excursion once. And I've worked myself up to flying in some fairly gusty conditions in the last year and a half. Thinking back to my lesson days, I couldn't imagine flying my instructor's machine solo on those type of days.

Even if safety weren't the ultimate reason for stabs and CTL, I would still choose both for the ease of flying machines with them. Even though I don't have extensive experience in other machines since we got our own, I believe I can get just as big a thrill flying our machine as RAF claims they can only get without the HS.

We have three members in our club who fly RAF machines. Until last year, ONE, who had tried an HS, didn't install his HS. But TWO, who did have a HS, and ONE, flew each other's machines at our 2003 fly-in. ONE had no trouble flying TWO's machine, while TWO could not fly ONE's machine for more than a few minutes, without having to hand control back to ONE. At our fly-in this year, ONE showed up with his NZ version HS attached. When asked about it, ONE said after flying TWO's machine, he felt it was time for the HS to stay on. And this is even with the cabin hop ONE has not been able to cure. I apologize for using the acronyms, but I'm not sure how either member would appreciate their names being used. The bottom line to this confusing story
is that a confirmed non-HS owner was converted, possibly after experiencing flying the two types of machines so closely together.

For the life of me, I just don't understand why Jim and Duane resist promoting the HS to their new students. If they want to avoid some kind of liability issue, just say the HS would make the machine easier to fly. I agree it's not the best reason, but if they can't use the real reason for whatever issue they're trying to avoid, they could still steer the students the right way.

[StanFoster]

I would like to add that I have never flown my RAF without its stab...and never intend to. I am very pleased with the feel it has.

I have ridden in Dofin Fritts machine...but it was my first flight in a RAF and I wasnt aware of what felt normal.

Stan

[pwendell]

Stan,

I think you know that I certainly have no problem at all with you or your aircraft. I doubt anyone else on this board does either. In fact, I'm jealous of all the hours your getting in! I'd fly with you anytime.

[Chuck_Ellsworth]

Quote :

" For the life of me, I just don't understand why Jim and Duane resist promoting the HS to their new students. "

It is quite simple, They are exact mirror images of Don LaFleur and Pete Haselow, either dishonest or stupid, or both, and seemingly without a conscience, the sad, sad record of RAF fatalities don't seem to have changed their ways...it is noteworthy that every RAF instructor that challenged Don and Pete on the stab issue are no longer associated with RAF.

But sooner or later they will be history and the gyro community will be far better off...

Chuck E.

[Jerseywing]

Jim is a veteran pilot who is self taught in Gyros. He took it slow and easy and learned on the ground before he lifted a wheel. He has over 3,000 hours in the RAF. I'm training with him now and he is more than willing to share his knowlege and experience with me. I can't compare it with others as I havent flown another but his gyro will pretty much fly itself if you don't mess with it. As far as a stab or CLT his attitude is that if I want one get it - not a problem. Part of his philosophy about PIO is not to teach you how to get out of it but rather how not to get into it to begin with. I have an enormous amount of respect for the man and his accomplishments. He is more a mentor than instructor. I'm new to the sport and will get a stab (and maybe even a conversion kit I'm not sure yet). The impression I get from these posts and the rest about the airport is that of a group of people who can't stand each other and don't trust each other worth a damn. It's easy to knock someone with a keyboard but how many have the balls to say it to their face? I'm glad I never have to go to sea with any of you. I've got to admit you folks sure made a real impression on me.

[KenSandyEggo]

Geez, Mike, I hear you, but somehow I just have a difficult time believeing someone who twists the truth with plagiarism to prove a point that has been shown time and time again to be a killer of gyro-heads. Has he shared his "knowledge" with you that it is just fine to do a full-power climb and then push the stick forward at the top without reducing power? That's what he tried to prove here and got exposed for lying, rearranging the wording in the FAA Rotorcraft Manual and plagiarism while trying to prove his ridiculous concept. Have you even read my post #27 in this thread?

Unfortunately, Jim lives on the east coast and I live on the west coast, but I ever meet him again someday, I will surely ask him face to face, "Jim, what the hell were you thinking when you posted that phony stuff?" He could have responded here directly when it happened, but he chose instead to just disappear from the Forum and to my knowledge, hasn't been back since. He didn't offer a rebuttal, a comeback of any sort, an explanation, or what he should have offered, an apology to all that may have believed him if his bull**** wasn't caught, and who would have most likely died following his advice.

I hope I never have to go to sea with you either. Gullible people who attempt to defend people afraid to defend themselves and act as their surrogate mouthpieces don't make good shipmates either. You're just another in a long line of RAF apologists and gullible people who have NOT made a real impression on most of us. We've heard it all before by even more rabid fans than you of slick, truth-twisting CFIs.

[Chuck_Ellsworth]

Hi Ken :

I can't believe that after all these years we are still trying to save all these poor ignorant victims of RAF's dishonest crooked purveyors of death.

How many more victims will we be trying to get the truth out to?

I just can't believe that RAF is still in business.

Jerseywing:

Has it ever occured to you that Jim and Duane are the only so called instructors in this business who teach their students utter crap that any knowledgeable instructor would laugh at if it were not so serious.

Here is a good question you can answer for me.

How many gyro instructors have you flown with?

Chuck

[Jerseywing]

Thank you both for proving my point...Mud slinging is easy when you can hide behind a keyboard... Neither of you have ever met me yet you sit in judgement of me. Amazing.

[mcbirdman]

Hey Jerseywing. Just take the physics of it into consideration. Just read up on RAF history. Take note that in the whole world these two people are the only ones "holding out" and YOU choose to trust and listen to. Sounds like you pretty much made up your mind anyway.

Research will show you the truth and possibly save your life. It isn't mudslinging there are problematic design flaws that aren't just simply a choice that is the same as choosing what type of candy bar you will ingest. Don't get mad at them for letting you know because in reality RAF isn't letting you know. Don't worry - you are not the first to be taken aside in the dark. It happened to me. Hey.... you sound like you like it. Want to buy a watch too?..... ;)

I knew 3 guys in Michigan that bought into the bull. One of them is still alive and probably still believes it is just a low significance choice. Only reason I think he is still around is because his diabetes caused vision problems and his is still in the trailer. Hey - it is your life to protect and you can invest your trust where you want it. Those guys are just trying to wake you up concerning the only 2 holdouts left. You want to be the realitive newbie and subscribe to this ridiculous company mentality I wish you luck but you were told. jtm

[Chuck_Ellsworth]

We are not sitting in judgement of you.

We are trying to jolt you into the fact that you are being missled by Jim and RAF.

We have no idea of what kind of a person you may be, but still do not want to see you die because you are being sadly missled.

Many people have been insulted by our posts, but most have finally realized we are only trying to save your life.

Mudslinging is not what I am doing Jerseywing, I'm trying to give you good advice.

And I would appreciate it if you withdraw your snotty remark about me hiding behind a keyboard.

Chuck E.

[KenSandyEggo]

"Neither of you have ever met me yet you sit in judgement of me. Amazing."

What's truly amazing is that you have the gall and balls to post the above after you posted the following. You threw a bunch of mud on a "group of people," calling them hateful and untrustworthy We only threw it on you selectively because of your defense of lies and dangerous misinformation by Jim Logan. Come out to San Diego with Jim, we'll have a good meal and a beer or beverage of choice and politely talk about it. Jim can talk about it right here, just like we are....as close to face-to-face as we can be, considering the distances involved. Jim chooses not to. No one is hiding here. We're all posting here under our real names. Have you mistaken this Forum for some newsgroups that allow anonymous posting?

Here's what you posted prior to being offended by being "judged." You seem very capable of judging others that you've never met. Use some logic in your future posts, please.

"The impression I get from these posts and the rest about the airport is that of a group of people who can't stand each other and don't trust each other worth a damn. It's easy to knock someone with a keyboard but how many have the balls to say it to their face? I'm glad I never have to go to sea with any of you. I've got to admit you folks sure made a real impression on me."

[Udi]

...Part of his philosophy about PIO is not to teach you how to get out of it but rather how not to get into it to begin with...
Not getting into a PIO should be a safety measure inherent to the aircraft itself. A stable gyro with a properly designed stab will not PIO and will not PPO. Learning how to avoid PIO and PPO in an unstable gyroplane like learning how to not fall from a unicycle. What's your objective? If you enjoy the challenge of flying an unstable aircraft and not becoming a statistic than by all means fly an unstable gyro. If you want a safe and friendly gyro to fly, get yourself a stable machine. It’s that simple.

Udi

[Jerseywing]

Advising me is one thing.. I understand the issues and if you read my post you'll see I will have a stab - no question. I just don't thing that its right to dog people, it's that simple. If people truly want to help, be constructive thats all. No one should go into this endeavour without doing their homework. It'll get you killed no matter what you fly. But calling people gullible c'mon ...The bottom line is that if you can't say something constructive then don't say it especially about someone else. I'll talk physics with you all day long. If you think I'm doing something wrong take it off line it's the appropriate venue for that. But realize as a newbie I read this forum and see alot of bitchin and mostly from the senior members. Talkin trash about stuff that happened in the past it's just not for me. As far as instructors go the PRA cant be doing that great of a job promoting the hobby when there is only one CFI in the NY metro area. So instead of crushing someone else here why not try and promote the sport through constructive conversation and informative posts. i.e. I've seen pictures of RAF's with dropped keels how do you do it? Never seen that discussed,,, That would make 'em safer. The reality is that there are two reasonably priced enclosed machines available and one is still proving its worth.

[banaari]

...Part of his philosophy about PIO is not to teach you how to get out of it but rather how not to get into it to begin with...

Genuinely curious, does he actually teach how to recover from a PIO situation?

[KenSandyEggo]

"Talkin trash about stuff that happened in the past it's just not for me."

You're not interested in learning about how many stabless RAF drivers have bunted over to their deaths in the past? You're not interested about lies told by RAF CFIs and management in the past? What are you doing here? Everything posted here is about something that happened in the past....even your original posts.

Obviously you hear about it from the senior members. It's obvious that it takes time to find out about it. You're new and you didn't know about it, so who do you expect to find out about it from? We went through it ourselves, but chose to wake up and realize what was going on....a point you haven't reached yet.

[Jerseywing]

Jeez Ken get over it... It's not what you say but how you say it. can't you prove a point without without insulting people? You want to tell me facts do it! I'll take them digest them and decide on them. Just don't dog others to prove a point.

[Chuck_Ellsworth]

Jerseywing :

First you acuse me of hiding behind a keyboard, now you are saying I'm talking trash.

The truth is the so called instructor you are so impressed with is the one who is spreading "trash" with his blind devotion to Don LeFleur and Pete Haseloh with their snake oil sales pitch that that killer they sell to the unimformed is stable and safe.

Did you know that RAF have had four of their own people killed in Kindersley flying in that death trap?

So I'm still waiting for you to withdraw that stupid remark that I'm hiding behind a keyboard. And we can just agree to disagree.

How about it?

[pwendell]

Talkin trash about stuff that happened in the past it's just not for me.

Mike,

To paraphrase a smarter man than me, "Those who fail to learn the lessons of history are doomed to repeat them."

I can promise you that every 'senior member' here who you feel is 'talkin trash' or 'coming down on you' is doing so only out of the sincere desire that you not pay with your life to learn history's lessons--lessons already learned, in some cases, by friends and comrades who are no longer here to share their experiences.

There is an awful lot of information now available to you on the internet. I recommend that you ask questions and take the time to read and understand why these experienced pilots hold the views they do. As a self-proclaimed newbie, perhaps a little humility might help to leven your growth as a pilot.

[Chuck_Ellsworth]

Jerseywing:

Jim Logan has been teamed with Don LaFleur and the Haselohs since 1992, I also was at that time involved with RAF and was attempting to set up their flight training program.

I very soon realized that RAF were just plain dishonest snake oil salesmen.

Jim stayed and is part of that group that continue to misrepresent and misslead those who know nothing about gyro stability.

Jim in my opinion is a disgrace to the meaning of CFI.

Are you aware that RAF has had four of their own die in Kindersley in that killer they flog to the unsupecting public?

I can understand your sticking up for a friend, but what he is teaching you is dead wrong.

Anyhow it won't be long and you will see the truth.

Chuck E.

[Jerseywing]

The term "talking trash" was not meant to demean anyones experience or wisdom. It was meant to describe making a factual case a personal attack. Chuck... Thank you, you stated your experiences facts, (and an Opinion) but without "talking trash" . There is a difference. I appreciate all of your concerns. And will take them to heart. As far as humility goes - humility is knowing that there are many things you don't know and being willing to ask others for for the answers. In that I am a humble person. Wisdom is the experience gained to be able to share that knowlege.

[mcbirdman]

Look - you admit being a newbie and yet you were talking so knowledgeable from your experience that you admit is .... limited. You seem to be more upset with getting told something you don't want to know than than we are about losing friends. If you want it watered down and think that being straight out is too hard for you then maybe you already are bothered by your mistake. You were excited about something that is exciting but we are more excited by these losses. Every so often a newbie jumps in with enthusiasm and all the facts and figures figured out. They don't like the message or being embarressed that the truth they thought they were given isn't anything like reality. Don't be embarressed or felt put down.

You have been able to see in just a few posts that there is far more you don't know than you expected. If nothing else you are now realizing that this isn't a normal chat room. We all care because we take the time to help others. Yes we want this to grow as you were questioning.... but with every preventable loss we all suffer in other ways. We lose friends and the gyro community in general continues to suffer the perception that it is abnormally dangerous to build and fly gyros. So, faced with not saying anything or just trying to get along - something must be said because we care. This forum is very valuable and imagine how long it would have taken you to realize all these things on your own.

As far as facts vs opinions..... You research it and I know you will be stunned at how long and often these type of situations have occured. There has been many people like you who have trusted in that company and have paid with their lives.

The shortness and directness of the posts come because we are not just messing around, especially when there has been so many losses. Many people just like you have stepped up and thought they were different somehow. That is why the past matters so much. Especially when the company isn't changing anything . In other words they are still in the past and so their past continues today. Other companies have moved from the past by learning from mistakes and should be viewed as much more suitable company to keep. It is exactly that important in my estimation. What does being a nice instructor have to do with the issues of building a hut out of straw or brick? You need to decide what you would put your life in concerning the activity you are engaging in. Luckily you will read stuff in this forum that may not be what you are expecting but can save you years of frustration and add years to your life. Take care, jtm

[Chuck_Ellsworth]

See how easy it is!

You are already one of us and learning just like we did.

Fly safe my friend.

chuck

[ben]

i am also a student of jim logan i find him to be a honest man and a very good teacher.and i am not going to sit back any longer and let you guys bad mouth him any longer. you know when i asked his why he doesnt post on this forum. he didnt say a bad word about any of ya, and yet you all do nothing but talk **** about him its a shame he has 2800 hours on his raf and you guys say its luck.

[pwendell]

he has 2800 hours on his raf and you guys say its luck.

Ben,

Whether it's luck, skill or a combination of the two doesn't really matter. There is plenty of empirical evidence that high thrustline gyros without horizontal stabilizers are not, and cannot be, stable aircraft. They are significantly more dangerous than CLT gyros equipped with an effective horizontal stabilizer. This is a fact. Anyone who disputes this is simply uninformed or lying. If someone disagrees with this, no matter how experienced they are, ask them for data that supports their arguments, other than their own experience. There is plenty of data available to support what I have said.

I do not know Jim. I have said nothing bad about Jim. If he wants to fly and teach in an unstabbed RAF that it his, and his student's, business. If he teaches that his aircraft is safer than, or as safe as, a properly designed gyro with (near) CLT and an effective horizontal stabilizer, he is doing his students a potentially fatal disservice and he should be challenged publicly.

If you, as an informed adult, wish to continue training with Jim in his aircraft and/or to buy or build a high thrust line, unstabilized Gyro, that is your choice, but understand that you are assuming an unneccesarily high level of risk.

Please understand that there is nothing personal in this. I am simply sharing the objective physics of gyroplane design and operations as I have learned them over the past 2 years studying and flying gyros.

[mcbirdman]

A person can be honestly wrong. A person can also be a nice man. Is this about being nice or can you understand what is wrong? This isn't about one person.

You are missing the point. You are pointing to a high time former helicopter pilot and expecting the same performance from the "average" type of guy who wants to just hop in and fly as the brochure from RAF seems to imply.

With the obvious design flaws and history of crashes or the inferior parts being supplied or the lay low and don't say anything type of defense does nothing to improve the facts or history that has been documented. If you are going to get mad at something that hasn't been said - can't help it. If you can follow what IS being said you will see.... but only if you want to see, but you are going to have to decide which way you want to look.....

[KenSandyEggo]

"can't (sic) you prove a point without without insulting people? Just don't dog others to prove a point."

What the hell do you think you're doing when you post stuff like this!!?? :confused:

"The impression I get from these posts and the rest about the airport is that of a group of people who can't stand each other and don't trust each other worth a damn. It's easy to knock someone with a keyboard but how many have the balls to say it to their face? I'm glad I never have to go to sea with any of you. I've got to admit you folks sure made a real impression on me."

[KenSandyEggo]

Ben, why did he say he doesn't post here any more? I'll answer for you.....it's because he was caught red-handed in bold-faced lies, which is not being honest in case you didn't put 2 and 2 together. Neither is plagiarism and posting the words as your own, nor is scrambling sentences from 2 locations that refer to 2 distinctly different types of aircraft, and intertwining them in an attempt to deceive others that the made-up paragraphs refer only to gyros and it was safe to perform the deathly maneuver he was advocating.

What may surprise you 2 guys is that I once defended RAF much more staunchly and vehemently than you could even probably imagine. I argued and argued with the "senior members" here about their bashing of RAF. After numerous flat-out lies from RAF to over 30 RAF owners that caused at least one roll-over by another RAF-er (had to do with their junk ignition systems), Don saying in one breath (almost tearfully) that he can't get genuine Subaru parts because no one will sell them to him, and coming back a couple of weeks later, having forgotten what he just said, that RAF uses ONLY genuine Subaru parts, after replacing dozens of cheap, disintegrating components on my own RAF with absolutely no concern from them, after finally seeing the carnage that was happening in the stabless RAF gyros, and finally availing myself of a lot of the sage advice offered here, I finally woke up.

It pisses me off when I see another newbie come along that has been bull-****ted by the likes of Logan and Hunn and used as mouth-pieces for them in an attempt to justify their total lack of knowledge when it comes to basic aerodynamics. With all of their experience, they are woefully ignorant of basic flight dynamics. Some will say that they do understand the dangers, but sadly sold out to RAF to remain on their good side so they can keep selling RAF gyros and getting student referrals. You can take your pick. We didn't post lies like Jim did......lies that could have easily lead to people's deaths. If that's "talking ****" about Jim, too darn bad, because this scenario will be repeated over and over, whenever bull-****ted victims of his show up here telling us what an honest person and great CFI he is. THAT'S talking ****.

[birdy]

Hmmmm..................
Michael and Ben,if some of the things I'v said over the last few months sounded like they may prop up your arguments and you think that my experiance would back it up,then please don't,coz its a compleatly different argument.
Everybody knows I don't fly stabs.Thats my choice and I have reasons for that choice,but I'v never said that my machines are stable,and would never let a newby,or someone who has only flowen stable machines fly mine.

While I don't fly stabs and my machines arn't exzactly CLT,I will support these blokes in their argument.

I'v found these blokes to be good ,well meaning people,and are only trying to help.Most of them know wot they are saying and some have alot of experiance.[you could only imagion how I percieved some of their comments ,being and ozzy.]

I wouldn't know your instructor if I fell over him[or anybody on this forum actualy]but he sounds like he definately knows how to fly[no ones luck will last that long] and either dosn't understand stability or can't see the importance of it to the welfare of a nervious newby.

IMHO,He could definately teach you how to fly to a high standard,but he can't ,or won't ,teach you the airodynamics.The fact that he's flowen a standard RAF for so long and is still alive is proof of this.

No gyro is idiot proof,and a RAF is less idiot proof than most.

[GyroRon]

Ben,

Whether it's luck, skill or a combination of the two doesn't really matter. There is plenty of empirical evidence that high thrustline gyros without horizontal stabilizers are not, and cannot be, stable aircraft. They are significantly more dangerous than CLT gyros equipped with an effective horizontal stabilizer. This is a fact. Anyone who disputes this is simply uninformed or lying. If someone disagrees with this, no matter how experienced they are, ask them for data that supports their arguments, other than their own experience. There is plenty of data available to support what I have said.

I do not know Jim. I have said nothing bad about Jim. If he wants to fly and teach in an unstabbed RAF that it his, and his student's, business. If he teaches that his aircraft is safer than, or as safe as, a properly designed gyro with (near) CLT and an effective horizontal stabilizer, he is doing his students a potentially fatal disservice and he should be challenged publicly.

If you, as an informed adult, wish to continue training with Jim in his aircraft and/or to buy or build a high thrust line, unstabilized Gyro, that is your choice, but understand that you are assuming an unneccesarily high level of risk.

Please understand that there is nothing personal in this. I am simply sharing the objective physics of gyroplane design and operations as I have learned them over the past 2 years studying and flying gyros.



Peter, best post on this subject I have read in a long while!!!

Ben and JerseyWing, It is the fact that Jim is a instructor and teaches in a dangerous machine that bothers the majority of us. Instructors are role models to their students in most cases - anyone see Barnstorms attachments to Gary Goldsberry, or Automans attachments to Maxie Wildes, or Screws and my attachments to Steve McGowan??? - We all look up to our mentor in gyroplanes and follow their lead in most cases. Jims students - especially the ones who had or are buying a RAF - are encouraged if by nothing else but example, to fly their gyros in stock configuration which is very potentially dangerous.

If Jim was not such a nice guy, and good CFI otherwise, no one would bother him I believe. But the majority of the gyro community would rather see him teach in a more stable gyro - at least use a stab on that RAF Jim!!! - so that his students are safer during their time training and the students would be more likely to fly stable gyros right off the bat too. We all know Jim is a good guy and good instructor, It is just too many of us think he should do his students a little better and be teach in a stable gyro.

Now to Ken and Chuck and James, If you read his posts, JerseyWing already said he is putting a stab on his machine and other than filling him in about the Rod Ends and other builders tips, I think he knows what he needs to know by now.

[Dean_Dolph]

......Now to Ken and Chuck and James, If you read his posts, JerseyWing already said he is putting a stab on his machine and other than filling him in about the Rod Ends and other builders tips, I think he knows what he needs to know by now.Ron, you are right, while we all know that Ken and Chuck are correct in their assessment, I feel that their messages always appear to be directed toward the messenger instead of the message.

It is to Jerseywings credit that he has hung in here and hasn't bailed out from what could easily be taken as a personal attack. I know that isn't Ken and Chuck's intent. But their real message, which is the RAF design/manufacturing flaws, could easily get lost in all the verbiage.

Jim Logan and Duane Hunn aren't going to change their presentations to their students so it adds no value beyond pointing out that the machines they are instructing in are dangerous and then presenting why. We can't go wrong in sticking to the facts of physics/building & flight experiences and then hoping that the message is accepted and understood. Emphasizing an instructors stupidity or ignorance, I'm not sure which in this case, won't help in getting the point across.

[Gyropilot007]

Guys:
I'm currently training with Duane Hunn and will hopefully soon solo my machine. I have an RAF but I've equipped it with Larry Martin's 'Ultimate Stab'. I have also installed RAF's stabilator modification.

Duane has not in anyway tried to encourage me to remove the stabilizer. He has stated that it is not needed and will reduce the performance of the aircraft. Duane has explained that the patented RAF flexible mast greatly reduces the chances of PIO and PPO. But he has also stated that it is the decision of the owner/builder regarding whether or not to install a stabilizer.

I purchsed the RAF because it appears to be a reliable and safe machine if the pilot has the proper training and the aircraft is properly maintained. I plan to do both.

Bob McGuire

[GyroRon]

.

Duane has not in anyway tried to encourage me to remove the stabilizer. He has stated that it is not needed and will reduce the performance of the aircraft.

Bob McGuire

If he tells you it isn't needed and that it will reduce the performance of the aircraft, then what do you call that?

Both of these instructors are good guys and would not get the treatment they get if they just broke ties with RAF and put a stab on their gyros and continued to train.

They would still have plenty of business without the RAF ties and they would earn back the respect of the rest of the gyroplane community if they did just that.

[mcbirdman]

Dean, if someone bailed because they choose not to hear the message it may still have a positive effect in the fact our safety record remained unchanged. Someone may say that someone who didn't like being told the truth in a percieved harsh way was hurtful to the gyro movement because they don't fly or were discouraged but that would not be the truth. If they were to continue and we were worried about hurting someones feelings even though we explained exactly what we were concerned about - someone could end up hurt like many others who also decided to ignore the information as presented. A death hurts the gyro community far more than losing one member. It isn't for everyone and the people who fly have to be able and willing to learn. Look how many people we have lost this month. Is it 4 ? We can't be timid in trying to change the bad public perception that exists.

I did see what jersywing said about his intentions of using stab. I still thought it was important to take note that the stuff the instructor was teaching actually involves a whole lot of other things worth consideration including history, design and lack of basic aerodynamic understanding.

How much time do you think the instructor took letting jersywing know the long extent of the situation? If he really told him what was going on other than his own personal view that he shares with another instructor then I am sure jersywing wouldn't have gotten in. It is really hard to learn what is going on from someone that involved in such a decietful company so a student saying he knows doesn't make it so. And it is difficult and somewhat unnatural to suspect that an instructor isn't up to date with current knowledge or isn't that determined to offer the best information out there concerning safety first.

IF a person is to take the least important aspect such as how nice someone is instead of the more important questions - then they can benefit from consideration of more important factors than being nice.

Yes, jersywing pm'd me and I know he will be fine and he did appreciate the information. But then Ben walked in and it seemed like he didn't like the messenger and wasn't getting the message either. Not too hard to understand either since he also is torn between feeling confident with his instructor and being told by others that he is learning from 1 of 2 instructors around that are left in the RAF foal. He has to either tune us out and put his full faith in the instructor or continue training with the knowledge that he may not be getting the full information accurately. Personally, if I can't get the full straight out honesty of a situation and have to question the validity of such I wouldn't pay for it. You can get that kind of FWIW information for free here. The only thing about that however is that you will get to the truth a lot quicker from people that have nothing to gain but the satisfaction of helping a fellow gyro pilot. Can't blame Ben for thinking that you can go straight to the company to learn their machine and proper operation. That seems normal but the main point of all this writing is that it isn't a normal company, that is for sure.

It is beyond anyones control to submit a message and to know what part of the post is influential. If someone wants to look at a post as negative personal attack when another person understands it as constructive or caring - heartfelt message to encourage someone to consider where they get their information from is all we can hope for. No one knows what it will take to get someone to make the best use of the information. In this case I know that he IS listening and that makes it worth while.

[Chuck_Ellsworth]

Some direct question questions to Duane Hunn and Jim Logan.

Please post supportable evidence that the addition of a H.S. will "reduce" the performance of the aircraft. And corelate this statement by explaining why all those helicopter manufacturers add H.S. 's to their design?

Please show verifiable proof that the "Magic Mast" that Peter Haseloh's uncle designed in his mind will prevent a bunt over due to the high trhust line instability of their gyro.

My opinion is both of you are missleading your students and exposing them to needless risk because you do not have the strength of character to stand up to Don LaFleur and Pete Haseloh and refuse to shill for them.

If you do not defend your position with facts that can be agreed to by the rest of aviation then you will in my opinion have zero credibility.

Chuck Ellsworth

[Mayfield]

I believe:

1. That Duane and Jim are good and honorable men.

2. That their logic is seriously flawed vis-a-vis stability.

3. That they are so skilled that they could sucessfully fly the box it came in.

4. That a RAF 2000 fitted with a good stab is more stable than without a stab.

5. That a RAF 2000 with a good stab and CLT is optimal re: stability.

6. That lowering the engine also lowers CG (significantly) and therefore does not necessarily correct the HTL.

7. That we should not build aircraft that can bite you (hard) when you are doing everything right.

8. That a statically (or dynamically) unstable aircraft can/will bite.

9. That a statically unstable gyroplane is even more lethal than a statically unstable FW.

10. That when asked by new folks about safety or stability that we try to explain the physics without hostility. That we do so even when the questioner uses emotionally charged language.

R/S (for the non Marines out there, Respectfully Submitted)

Jim

[Doug Riley]

There are huge differences in skills and knowledge among (1) engineers (2) pilots and (3) mechanics. People who are really good at any one or two of these disciplines aren't necessarily any good at the other(s).

A good PILOT can make a very marginal machine appear to be a pussycat. With enough flight time, such a pilot can even teach a newcomer his special skills. The tricks involved in handling an unstable gyro include the following: (a) using pulse-and-return stick movements (b) using a "second jab" in the opposite direction after applying and releasing a stick pressure and (3) immediately snapping the throttle shut when turbulence or PIO are encountered. The first two are standard professional test-pilot techniques for handling static instability. The third is a technique specifically tailored to aircraft that, because of a high uncompensated prop thrustline, are prone to uncommanded pushover when the G-load on the rotor is reduced.

None of these techniques is necessary or particularly useful when flying a pitch-stable gyro.

A pilot with such advanced skills qualifies as a "good stick"-- an outstanding pilot in the gyro world. That doesn't confer upon him/her, however, ANY engineering knowledge whatsoever. None. It takes a whole different skill set to analyze the stability of an aircraft. Pilots and mechanics, however masterful they are at their specialities, have no leg up on any randomly-selected layman in understanding the science of stability.

Fortunately, some very bright people with engineering and physics backgrounds have done all the heavy lifting for us. In some cases, the work was done decades ago, but either forgotten, not well circulated or just ignored for commercial reasons. Among these people are Chuck Beaty and the Groen Brothers in the U.S., Juan de la Cierva in Spain, Jukka Tervamakki in Finland, Jean Fourcade in France and Stewart Houston in the U.K. Their work stretches over more than 75 years. Of the group, only Cierva and Groen are/were in the business of selling gyros.

They all came to the same conclusions: prop thrustline at/near CG is necessary for gyro stability and a horizontal stabilizer is necessary on a gyroplane. Note that the only two gyros certified post-war in the U.S. -- the Air and Space and the McCulloch J-2 -- both have large HS's placed in the center of the propwash and thrustline at or near the CG. (For that matter, the prewar gyros had the same features.)

Instructors who ignore or contradict this amount of technical wisdom sure have some explaining to do.

[GyroTyro]

confused: Please explain this statement. :confused:


[QUOTE=Mayfield]I believe:


6. That lowering the engine also lowers CG (significantly) and therefore does not necessarily correct the HTL. (???) :confused: :confused:

10. That when asked by new folks about safety or stability that we try to explain the physics without hostility. That we do so even when the questioner uses emotionally charged language.



If you lower the engine and prop say 6 inches without modifying the redrive don't you also lower the thrust line 6 inches?

I included point 10 just so you don’t get hostile while answering my question. :D

[Dean_Dolph]

James, you are a stupid ignorant ass!




Not really! :) :) But what did you feel when you read those words?

I would be very surprised if you didn't immediately get an adrenaline rush and go into a defensive mode. It is a natural reaction and we all know from personal experience that when we do that it tends to cloud our thinking and we aren't as receptive to anything that is presented from that point on. It is definitely not a frame of mind where we should be flying!

If you don't accept the premise that people tend to ignore what you say after you have insulted them, or in this case their instructor, then it is difficult to discuss the merits of presenting the info in a different manner.

If someone bails before they have heard or accepted the message then the gyro movement has a chance of being hurt. I think you misunderstood what I was saying. And quite frankly I'm not concerned about what the public thinks except I recognize that the public, if we are talking John Q instead of our aviation brethren, could have a negative impact on our flying. What I am concerned with is the means of reducing the incidents. This isn't about losing a Forum member, it is about saving someone from injury or death. And providing an environment where questions can be asked and views can be exchanged in a non-threatening manner has a chance of doing that. But there are no guarantees.

So yes, bailing out and thinking that this group is a bunch of jerks rather than realizing that we have peoples best interests at heart is a real possibility, And yes we all could suffer from some one bailing out. So, there is an incentive for us to be kinder and more gentle when trying to get the message out.

Jerseywing sounds like he has a thick skin and heaven knows that is an asset here! But he is new here, even if he has been lurking for awhile, so like any new member he doesn't recognize who the experts and knowledgeable people are. And without that knowledge how do you suggest he go about accepting what he is presented with?

Now, it is my, and others, belief that the majority of instructors, not only Logan and Dunn, are not teaching enough or the correct theory. But the question then comes up about whether that is the instructors role. Should Logan and Hunn, or any others, be held accountable for teaching theory or should they concentrate on teaching flying skills? I think it would be hard not to include some theory.

I have never flown with either of them but there are several old timers that say that they very skilled pilots with loads of experience to pass on. But I would rather they leave theory out altogether than pass on faulty info. I would say that the theory part can be take care of on the Forums but then there is no guarantee that all students will visit here. So, hoping I’m not contradicting myself, it is imperative that if an instructor is going to teach theory then it must be correct.

No, James, I'll stick by what I have stated about sticking to the physics, building and flying experience facts and leave the personal attacks out. Insulting a student's instructor is not the way to get the info across.

[pwendell]

Bob,

Unless Duane explained to you how the 'magic mast' and stabilator can make a HTL gyro without a horizontal stabilizer statically and dynamically stable, he essentially told you nothing at all. Did he even use the terms 'static and dynamic' stability? (Please note that aerodynamic stability is not the same thing as a subjective feeling of stability while flying). If you have not been taught about static and dynamic stability in gyroplanes then you really need to do it on your own.

The AAI website, http://www.americanautogyro.com, has a nice basic explanation of gyroplane stability. The Magni USA website has a wealth of detailed information put together by Greg Greminger, who is head, I believe, of the ASTM committe on gyroplane stability. You can find this at, http://www.magnigyro.com/USA/features.htm .

Feel free to share your learning experiences or ask any questions you might have here on this forum.

[mcbirdman]

OUCH !!!!! That is HOT !
just kidding.

Looks like you agree. But when you said

"No, James, I'll stick by what I have stated about sticking to the physics, building and flying experience facts and leave the personal attacks out. Insulting a student's instructor is not the way to get the info across."

I don't remember any of them saying that. Every post I saw took the time to say he is nice BUT nice isn't the same as being right. I just think others looked past the nice part first and then to the disagreement which is the opposite of what you were saying when you called me an ass.

In other words there was real sugar given to go in the coffee but the conflicted person was reacting to the coffee that evidently is hotter than what he thought he was getting. It is a normal response since it is something totally unexpected. I felt the same way.

Am I really? ;) take care, jtm

[Mayfield]

GyroTyro,

The engine on one of the "Dreadnought" class machines (Chuck Beaty's nicely put description) like a SparrowHawk or an RAF, can make up 40-50% of the total aircraft weight.

If you lower the engine you lower the CG by some amount that is proportinate to the ratio of the weight lowered to the total aircraft weight.

If the thrust line stays in the same place, relative to the mass of the engine, the relationship between aircraft CG and engine thrustline may stay very close what it was before you lowered the engine.

I'm not saying that there is no value in lowering the engine. I'm saying that lowering the engine alone may not bring large benefit re: engine thrustline aligned with aircraft CG.

I am certain that Doug Riley or Chuck Beaty can articulate this better.

This message edited after reading Doug's better description below.

R/S

Jim

[Doug Riley]

When you move weights around on an aircraft, the CG follows you like a puppy.

When you move a weight back, the CG moves back. When you move a weight down, the CG moves down.

The CG doesn't move as far as the weight moves. In fact, the CG moves the same percentage of the distance the weight moved as the weight bears to the whole aircraft weight.

Take Jim Mayfield's statistic. If the engine is half the aircraft's gross weight, then the CG will move half the distance that you move the engine. If you move the engine down six inches* using a "drop keel" setup, then the thrustline has moved down 6 inches, but the CG has moved down 3 inches. You've only cut the thrustline misalignment by a net 3 inches instead of the full 6. Flipping the redrive so that the prop shaft is below the engine crankshaft is a more efficient way to get things to line up.

* You could just as well think of the engine and thrustline sitting still and the rest of the aircraft being "raised up" around it on longer landing gear. The arithmetic works out the same no matter which way you look at it: in either case, you're moving half the weight and you get half the CG move.

[Vance]

Hi Doug, I love the way you explain things. I never had a puppy. Thank you, Vance

[Chuck_Ellsworth]

Dean :

Are you an instructor?

I am not trying to be confrontational it is just that I can't follow your logic.

For me it is pretty straightfoward, I am an instructor and believe that to teach flying safely it is my duty to teach my students "ALL" of the needed subjects.

To do this I do not have to be an engineer nor an expert on aerodynamics and the laws of physics because all that information is already avaliable with the conclusions well proven by those trained in those subjects.

Anyhow lets wait and see if Duane or Jim can answer my questions and back up their position with veriafible proof of same. I am really interested in that statement about a H.S. degrading performance the first time I read about that was when Dan Haseloh had another one of his many accidents and blamed it on testing a new stab....

Chuck E.

[Dean_Dolph]

confused: Please explain this statement. :confused:


[QUOTE=Mayfield]

6. That lowering the engine also lowers CG (significantly) and therefore does not necessarily correct the HTL. (???) :confused: :confused:

10. That when asked by new folks about safety or stability that we try to explain the physics without hostility. That we do so even when the questioner uses emotionally charged language.

If you lower the engine and prop say 6 inches without modifying the redrive don't you also lower the thrust line 6 inches?

I included point 10 just so you don’t get hostile while answering my question. :D No hostility here! I see Mr. Mayfield and Doug R., have already provide you with an answer so I'll just give you a different slant with the same result.

First you have to recognize that the two heaviest components of a flying gyro are the engine and the pilot. So it follows that moving the engine (or the pilot) up or down also moves the vertical center of gravity significantly.

But if you drop the engine and the prop both 6 inches then you have maintained their relationship and have had minimal impact on the high thrust line. The only place that you have helped it is that you have, in effect, raised the pilot's weight in relation to the prop thrust line which helps some what. But with an RAF thrust line that is reported to be somewhere in the vicinity of 10 inches you will be far from correcting the problem. What others have done, and it is the correct way, is raise the engine so that the redrive can be rotated where the prop is below the engine and more in line with the pilot and the Cg. This usually requires a dropped keel to provide for prop to keel clearance.

It doesn't matter what is moved as long as the prop thrust line passes thru the Cg or within plus/minus a couple of inches. The vertical Cg can be calculated using a spreadsheet that is available somewhere on the Forum or from someone here. In any case a horizontal stabilizer is required.

[Jerseywing]

I understand the proportionality you describe regarding the weight shift. Where I have a question is if you raise the engine doesn't that change the "tipping" moment or rotational axis. I understand the physics of a ppo but I'm confused on how lifting the engine helps. I realize you can then invert the redrive so you can move the thrustline lower but isn't it then like a lever under the engine so in a forward pitching motion it aids in moving the weight of the engine over? . If you were to get a straight through drive or direct drive and lower the engine what would the resiult be. Where is the ideal engine/cg/thrustline location?
Jeez now I'm confusing myself....

[Aussie_Paul]

....when I was in full swing with my modifying and testing Rafs on a daily basis. :D

Jim, that was a well written post, but I dissagree a little with 6).

Dean if you lower the engine and redrive it is not only the pilot weight that goes up but the whole weight of the machine except for the engine and redrive weight.

Not the ultimate BUT well worth the effort. On a Raf it is not a minimul change to the HTLM by lowering the engine and redive 6". It can be approx a 30 to 40% reduction of the CoM to thrust line offset, which in a stock Raf is around the 10.5". That is considerable compared to 30 to 40% of a more normal 6" offset.

I know that the $ should not be the motivating issue with safety, BUT it sometime is and has to be. To convert a Raf to Hybrid means the purchase of a gearbox. A new prop as the direction is reversed. A new tail as the "P" factor is also reversed. The advantage of a new tail is that it can be made larger to counter the Raf yaw instability with the doors on.

Lowering the Raf engine redrive combo, and having an effective stab with fins set at a negative AoA of approx 4 degrees, you have fixed the yaw instability with the doors on and brought the CoM to thrust line offset and stability to an acceptable level that I will solo and issue certificates to students without having to lose sleep worrying!!!!! :eek:

It certainly is not the ultimate, BUT it is an economical way to make a Raf quite use friendly without breaking the bank. This is certainly ahead of not being able to afford Jim augmentation kit or changing to my Hybrid version and flying a stock Raf.

I have written this with the intent to help some people, I hope that it is taken in that light.

I will try and dig out the pics I used to calculate the CoM of the NZ Raf that the boys in Nelson NZ modified several months.

If I remember correctly, it reduced the offset from 10.5" down to 6.5"

Aussie Paul. :)

[ben]

ken, i was on norm forum when he said about pushing the nose forward to leveling off to pattern altitude while still under full power before throttling back to cruise speed i couldnt figure what the big deal was its a move that i do when i get to pattern and have no problem with it.when i saw the post i had a lesson the next day and asked him about it and he told me that it was in the helicopter part of my book and it was.then i aked him why the helicopter part he told me that it wasnt explained well if at all in the gyroplane section. it made sense to me but you went off on him.jezzzes ken that was a year ago, let it go, ;) have a beer and a shot on me.

[banaari]

ken, i was on norm forum when he said about pushing the nose forward to leveling off to pattern altitude while still under full power before throttling back to cruise speed i couldnt figure what the big deal was its a move that i do when i get to pattern and have no problem with it.

Interesting: I'm still trying to arrange my first gyro lesson - but: the Attitude,Power,Trim sequence for top-of-climb definitely applies to FW aircraft, otherwise you let the (already reduced) airspeed bleed off even further, asking for a stall. The overriding concern in a gyro is very different, i.e. unloading the rotor. Speaking from a position of utter ignorance (no flames please!!) I would have thought the approach would be to reduce power, and let the a/c nose settle downward to cruise attitude as the climb rate dropped away.... weathercock stability in the vertical plane supplied by the horizontal stabiliser... ??

[pwendell]

Ben,

If Jim told you that, you should run, not walk, away and find a new instructor. The reason for not leveling out after a climb by pushing the cyclic forward whith the throttle still on climb power is obvious to anyone who knows even a little bit about how and why gyros fly. When you lower the nose at the top of a climb, you momentarily unload the rotor allowing rotorspeed to decay. This is bad practice in any gyroplane. In a gyro with a high thrustline and no horizontal stabilizer it is a recipe for disaster. The only thing keeping such a gyro from nosing over (bunting) in normal flight is the rotor's thrust. When you push the nose over at the top of a climb, you partially unload the rotor and reduce its ability to couteract the engine thrust that is trying to push entire gyro over when it is most needed -- under full power. This is an extremely dangerous flight profile. If you are unfortunate enough to encounter some moderate wind shear or a moderate downdraft at this moment, unloading the rotor even further, your could pushover in an instant and become statistic -- a beer and a shot won't help.

Gyros are not helicopters. They do not fly like helicopters. What is acceptable in a helicopter is not necessarily acceptable in a gyro. Just because the Rotorcraft Flying Handbook describes a maneuver for a helicopter does not mean it applies to a gyro.

If you don't believe me or the other folks here, grab a phone an call another CFI. Call Greg G., Terry Brandt, Doug Riley, anyone other than Duane Hunn, and ask them.

[Mayfield]

Paul,

I certainly agree with you that lowering the engine even 6 inches is better than the stock thrust line offset.

As you implied, it is a matter of degree. When I stated that a typical engine weighs 40-50% of the gyro weight I was talking empty weight. Doug tactfully pointed out my slip of the keyboard.

The weights of interest are weight moved and flying weight.

To put real numbers to it:

1. If the engine/redrive/heat exchangers/exhaust, etc. weigh approximately 300 pounds and;

2. If the gross weight is 1300 pounds;

3. moving 300 pounds down 6 inches will move the CG down 300/1300 = .23% X 6 inches = 1.38 inches.

4. This means, using your calculation of a 10 inch thrustline/CG offset, that we still have a little over 8.5 inches (fixed by Udi inpost below to 5.38 inches! Thanks Udi.) of offset left. Coupled with your effective stab this may be enough. Our calculations (and measurements of RAFs brought into the shop for mod kits) show a typical offset of a little over 12 inches. I'm sure it varies from ship to ship.

So; yes it helps. Enough? As you and I have discussed before, it's all a matter of degree.

If my Alabama "ciphering" above is in error I count on brighter people to catch it.

R/S

Jim

[Udi]

1. If the engine/redrive/heat exchangers/exhaust, etc. weigh approximately 300 pounds and;

2. If the gross weight is 1300 pounds;

3. moving 300 pounds down 6 inches will move the CG down 300/1300 = .23% X 6 inches = 1.38 inches.

4. This means, using your calculation of a 10 inch thrustline/CG offset, that we still have a little over 8.5 inches of offset left. Coupled with your effective stab this may be enough. Our calculations (and measurements of RAFs brought into the shop for mod kits) show a typical offset of a little over 12 inches. I'm sure it varies from ship to ship.
I think you gave permission to correct the numbers, Jim.

1. If the thust line (the prop) moves 6" down,

2. And the CG moves down 1.38"

3. Then the new thrust line offset would be 10" - 6" + 1.38 = 5.38"

Udi ;)

[Udi]

...If Jim told you that, you should run, not walk, away and find a new instructor. The reason for not leveling out after a climb by pushing the cyclic forward whith the throttle still on climb power is obvious to anyone who knows even a little bit about how and why gyros fly. When you lower the nose at the top of a climb, you momentarily unload the rotor allowing rotorspeed to decay. This is bad practice in any gyroplane. In a gyro with a high thrustline and no horizontal stabilizer it is a recipe for disaster. The only thing keeping such a gyro from nosing over (bunting) in normal flight is the rotor's thrust. When you push the nose over at the top of a climb, you partially unload the rotor and reduce its ability to couteract the engine thrust that is trying to push entire gyro over when it is most needed -- under full power. This is an extremely dangerous flight profile. If you are unfortunate enough to encounter some moderate wind shear or a moderate downdraft at this moment, unloading the rotor even further, your could pushover in an instant and become statistic -- a beer and a shot won't help...
I have to dissagree with you on this one, Peter. In both FW and gyroplanes the correct controls are stick for airspeed and power for altitude. So, if you climb at 55 MPH and then you want to accelerate to 75 MPH at the top of the climb, the correct thing to do is to lower the nose as you approach your altitude and let the gyro gain airspeed. When you reach your intended airspeed, you would reduce power to maintain altitude. There is no other way to gain airspeed other than lowering the nose or, as you say, pushing the stick.

You were correct to note that a low G event would slow down the rotors, but leveling off out of a climb does not require that kind of negative G. You start leveling off well before you reach your target altitude and if you do it gradually enough you woudn't even feel light in the seat.

Banaari - stable gyros and FW are flown almost the same, with the exception that negative G's are a no-no in gyros.

Udi

[pwendell]

So, if you climb at 55 MPH and then you want to accelerate to 75 MPH at the top of the climb, the correct thing to do is to lower the nose as you approach your altitude and let the gyro gain airspeed. When you reach your intended airspeed, you would reduce power to maintain altitude. There is no other way to gain airspeed other than lowering the nose or, as you say, pushing the stick.



Udi,

Respectfully, lowering the nose under full power in an HTL, stabless gyro is potentially hazardous. In my opinion, the correct procedure for leveling off in such a machine is to reduce power to cruise and then add forward pressure to reduce angle of attack and increase airspeed. In practice these two things happen nearly simultaneously. The important thing is not to 'push over the top' at full power since it puts the gyro into a more vulnerable state.

In the gyro I've trained in, an AAI modified RAF, climb and normal cruise speeds are virtually the same. At the top of my climb I always reduce power to cruise and then add forward pressure as necessary to maintain airspeed, or accelerate, if desired. If I've misjudged my power setting, I simply add or remove power as necessary to maintain altitude once the desired airspeed has been achieved. The principles you correctly wrote 'power for altitude, pitch for speed' are observed. Only the timing is different.

I am, of course, always willing to hear from other pilots and learn from their experiences and my mistakes.

[Mayfield]

Udi,

As always I appreciate your lucid look at things! Hopefully someday my fingers will keep up with my brain.

If the CG stayed magically in the same spot then a 6 inch engine drop would reduce the offset to 4 inches. But since the CG dropped down another 1.38 inches then the new offset would be 4 + 1.38= 5.38.

Jim

[Aussie_Paul]

With my Hybrid, I train the same as a fixed wing instructor trains. Power Attitude Trim(PAT).GEEZ!!! :( I must have been tired when I wrote that. I should have continued and said "for levelling off Attitude, Power Trim (APT)." This could never be done in my previous HTLM trainers. :eek: I do not train people into HTL machines. If they refuse to have a CLT with an effective stab gyroplane I will not train them. All but one I have been able to convince with reasonable discussion. ;)

This one person who did not come back after I told him to either reverse the gearbox or don't come back. Now he is ringing me to see if we can get rid of this "nosing over" feeling that he now feels as the thermals begin to show up!!!! It is amazing how some people are more concerned as to how their machine looks rather than the safety!!!!! Bright and shiney HTLM or a non painted CLT with an effective stab machine to go to a flyin!!! :eek: I am not too proud to turn up with a safe unpainted gyroplane!!!! :D

I have one newly certificated pilot who has a HTL gyro, and we are in the throes of changing it. This person is a natural and has many hours of sailplane flying, but he wants to improve his machine. Now that makes me feel good!!!! :D

I just love stable gyroplanes that I can solo people into and not have to worry at all. To think that you can have stability and the manoeuvrability of a helicopter is just great!!!! :D

Aussie Paul. :)

[ben]

udi, that is what i was trying to say, stick for airspeed and power for altitude,thank you

[mrford61]

I have read a number of times re the 3 or 4 degrees on the stabilizer.

I assume it is to give a nose up deflection relative to straight and level flight. I also assume this is to resist a PPO.

My thinking though is that in the very first stages of a PPO ie. the attitude of the aircraft is not in line with the flightpath, a FLAT stabilizer very quickly, by default, progressively gets 1, then 2 then 3 then 4 and so on degrees AOA in relation to the flightpath and starts pushing the nose back up.
So really, all the 3degrees set AOA is, is a headstart on what will happen anyway as the nose over starts.

So I am thinking that you will be "dragging" that 3 degrees in normal flight when it may not be necessary, particularly on a CLT machine.

Or is it offset by less rotor AOA????

At what AOA would a FLAT stab be when your rotors are likely to start banging in a PPO. I would have thought very high????

Hope you all understand what I mean and help me get my brain around this.

Thanks.
Mark Clifford - Australia

[mceagle]

Udi, I agree with you totally - re level off then power back. I had many disagree with me a few months ago on this subject but it seems most fly off at at the wrong tangent without listening to what is said. No one to my knowledge has ever suggested "pushing the nose over". A simple matter of lowering the nose is not even felt as a "G" change and is part of any normal flight regime in a Gyroplane (you have to reduce "G" to take weight off the rotors, and the "G"'s have to reduce to zero to totally unload the blades). Any Gyroplane that PPO's after this manouver is close to doing it anyway and is dangerous and should not be flown.

Peter W. In my opinion, there is something wrong with the AAI modified RAF that you trained in. The best climb speed and the cruise speed should not be virtually the same. Either the climb speed is way too high or the cruise speed is very slow for that aircraft. Perhaps Jim could fill us in here.

G'day Mark - I agree with your post. The 2 to 4 degrees angle of attack on the stabilizer is an incorrect assumption made by many after learning just enough about the subject to get themselves into trouble. The angle of attack of the stabilizer should be relevant to the airflow, which may well have no relationship to the rear keel at all. In any case, if the gyro is correctly hung, the C of G will be ahead of the rotor thrust vector, causing the gyro to tend to fly a few degrees nose down. This in turn will give a keel mounted H/S a negative angle of attack anyway. Just enough angle of attack would be required to "pre-load" the stabilizer enough for the gyro to fly level. adding too much extra would not only cause unnecessary drag, but could concievably cause premature stabilizer stall when it is needed the most.

[Aussie_Paul]

Mark, you only need the negative 3 or 4 degrees in a HTLM. For CLT the stab should be neutral.

Aussie Paul. :)

[Aussie_Paul]

..... (eg. stock Raf, heaps of horsepower) you definately have to reduce power before, or as you lower the nose to s/l attitude, otherwise you will find the nose going down in the beginning of a PPO. The reduction in "G" does not have to be very great at all in these types of machines.

Aussie Paul. :)

[chuter]

Tim said:
In any case, if the gyro is correctly hung, the C of G will be ahead of the rotor thrust vector, causing the gyro to tend to fly a few degrees nose down.

My understanding is that this is not necessarily correct. The hang angle is used to center the stick to ensure there is adequate control movement available fore/aft.

The relationship of the rotor thrust vector to CG is the result of forces from the thrustline/CG relationship and aerodynamic forces on the airframe.

Experts please correct me if I'm wrong. :o

[mrford61]

Thanks Tim and Paul for replying re Horizontal Stab.

What about my other comments that in the first stages of a PPO you would quickly get your negative AOA anyway, are they valid or way off the mark?

Another cat in the pigeons... regarding the consensus that the stab is more effective immersed in propwash. Given that the propwash would be the overriding force on the stab, and the stab is fixed to the same platform as the prop, wouldnt that negate the horizontal stabiliser???

Imagining the gyro tumbling forward under power (PPO) isnt the stab getting no resistance from the relative airflow because of the overriding force of the propwash, which is just following the stab in the tumble.???

Please understand I am not making statements here, just asking questions

Really appreciate any comments.

Mark Clifford - Australia

[Doug Riley]

Mike Guard, you're right. Whether the CG is ahead of or behind the rotor thrust line will depend on what other forces are acting on the airframe. A high prop thrust line, for example, will swing the CG down-and-back relative to the rotor thrust line, setting up an unstable situation. All stock RAF's -- including those with HS's -- have this defect to a greater or lesser degree.

Mark, immersing the HS does NOT prevent it from sensing the surrounding airflow. The prop wash deflects in response to changes in the direction of the surrounding airflow.

This is easily proven with a couple of electric fans and some bits of yarn. Tie the yarn tufts to the grille of one fan. Turn it on and observe the direction that the tufts blow in. Now turn on the other fan and place it upstream so that it blows into the intake side of the first fan. Move fan #2 around, pointing it into the intake of fan #1 at various angles. Watch the tufts respond, evn though they are immersed in fan #1's wash. The wash "bends" in reaction to the direction of the inflow.

All the professionally designed pusher gyros -- from the 1930's Buhl on through the McCulloch J-2, Air and Space, Groen and Carter machines -- have HS's centered in the prop wash. So do fixed-wing pushers such as the Cessna Skymaster and Seabee. These craft wouldn't -- couldn't -- have the HS where they do if the propwash made it insensitive to the surrounding airflow.

Bensen simply blew the HS issue on his B-8 gyro and was either too proud or too tied up in legalisms to fix the problem. Instead, he just let people die and blamed it on failure to follow directions. Others, not knowing any better, copied his design but made it worse by using redrives offset above the engine. We're still trying to dig ourselves out of that hole.

[gyromike]

Another cat in the pigeons... regarding the consensus that the stab is more effective immersed in propwash. Given that the propwash would be the overriding force on the stab, and the stab is fixed to the same platform as the prop, wouldnt that negate the horizontal stabiliser???

Imagining the gyro tumbling forward under power (PPO) isnt the stab getting no resistance from the relative airflow because of the overriding force of the propwash, which is just following the stab in the tumble.???


It doesn't work that way Mark.
The airflow coming off off the prop is not always parallel with the thrustline.
Crooked air in, crooked air out.

Consider the rudder and vertical stab (or all-flying rudder).
If the airflow were always parallel to to the thrustline, your vertical stab and rudder (immersed in the prop wash) would be ineffective, unless you displaced the rudder with the rudder pedals. If the surfaces are "shielded" by the prop wash, why does the machine continue to go straight if you hold your feet steady on the pedals, effectively locking the rudder in place?

Because the propwash is affected by the relative wind entering it and surrounding it. It moves the propwash around, though not as much as the change in relative wind. However the increased speed of the propwash vs. the relative wind gives it plenty of lift (sideways, but still lift).

The same goes for a horizontal stab in the propwash.

[Chuck_Ellsworth]

May I suggest that factoring G load into the process of changing your flight path from the climb to level flight is causing "fuzzy" thinking in this conversation.

It is very simple, when leveling off from the climb to level flight there will be very little change in G load, unless you agressively move the cyclic foward.

The uncommanded pitch excursions in a high thrust line gyro are a result of the prop thrust acting like power steering in a car and overcontrol becomes much more difficult to prevent due to the "power steering " only acting in one direction.

The actions required to change from climb to level flight are A. P. T.

The actions required to change from level flight to descending flight are P. A. T.

These are basic aircraft handling proceedures that must be taught in the first flight lessons with Attitudes and movements.

Don't make simple things difficult by factoring in G load in normal aircraft handling actions.

Chuck E.

[Udi]

I suspect that in the AAI modified RAF Vx and Vy are close enough to 65 MPH that Jim and Terry decided to make it simple for the students and fly only at 65 MPH. My old single place Air Command for example had a Vx and Vy of about 45 MPH and my cruise speed was about 65 MPH.

Mark Clifford - the thrust-induced PPO nose-down pitching moment of a HTL machine is not a function of airspeed, it's only a function of the power setting. To counter, or minimize, that nose down moment, people install a stab in the prop wash with a negative angle of attack. The purpose of the negative angle of attack is first of all to take advantage of the prop wash to counteract the nose down pitching moment of the engine. A negative AOA stab in the prop wash is providing a nose up pitching moment that is proportional to the prop wash - thus proportional to engine power. A perfectly set up HTL machine (Hybrid? Magni) would have a stab that completely cancels-out the engine nose down pitching moment, and then adds just a little more nose up pitching moment, for positive static stability. That is how HTL machines like the Magni can be stable. A secondary purpose of the negative pitched stab is to provide airspeed stability. But that is just a bonus because most gyroplanes are airspeed stable anyway due to rotor blowback.

Tim mceagle has mentioned the relationship between the hang test, the keel flying angle and the angle of the stab in flight. Many people get this part wrong, because this relationship is hard to visualize. Mark chuter mentioned, correctly, that the purpose of the hang test is to center the cyclic in flight. But remember that this test is assuming a given rotor AOA in flight. The actual angle of dangle of the gyro in flight also depends on your specific rotor and on airspeed. The rotor AOA is higher at a low airspeed and lower at a high airspeed. The rotor itself "doesn't care" how your gyro dangles. The Rotor AOA is determined only by weight and airspeed. The rotor thrust line vector (RTV) is perpendicular to the rotor AOA.

So, the angle of dangle, in flight, is determined by the static hang angle (i.e. the location of the CG with relation to the teeter bolt), by the angle of the RTV (airspeed specific), and by all the other pitching moments that act about the CG under any given condition (they include engine thrust and aerodynamic forces (lift/drag) due to fuselage and stab). The only practical way to determine the angle of dangle in flight is through flight-testing. But you can make your life easier by aligning the drag, thrust, and lift with the CG. This is the basis for the design of a true CLT gyro.

Udi

[pwendell]

I suspect that in the AAI modified RAF Vx and Vy are close enough to 65 MPH that Jim and Terry decided to make it simple for the students and fly only at 65 MPH. My old single place Air Command for example had a Vx and Vy of about 45 MPH and my cruise speed was about 65 MPH.



Udi,

Vy in the AAI modified RAF is about 65mph and we generally cruise at around the same speed, although not always. Leveling off in this machine is simply a matter of reducing throttle to cruise and letting the nose settle to trimmed pitch.

I stand by what I said about reducing throttle at the top of the climb in an HTL, stabless gyro. I try to think about these things from the point of view of a student or low time gyro pilot. Is it really smart to have a low time pilot leveling off at full power in a machine that is prone to PIO and bunts? If the low time pilot overshoots, he could be in trouble. If he hits some turbulence while leveling off, he could be in trouble. There is no reason not to reduce power to cruise first and then lower the nose, or let it come down on its own (remember that in practice these actions happen almost simulaneously). Sure, maybe you accelerate to cruise speed more slowly this way -- a few seconds slower? -- but it is definitely safer, even for experienced pilots. The less time you spend in the highest risk configuration -- level flight, full power and forward pressure -- the better.

Pilots in stable gyros don't need to operate this way.

[Doug Riley]

..and recall the article in a recent PRA mag by an Englishman flying a Cricket (a no-HS Bensen derivative with a pod and low CG). He appears to have come very close to PPO a couple of times as a result of lowering the nose after initial climb while the power was still up.

You really do have to tiptoe around the danger spots in the flight envelope of some of these unstable machines... even to the extent of using some awkward or seemingly wrong-headed control inputs.

Another reason to get such craft fixed ASAP.

[Udi]

As Tim said before me -- any gyro that will PPO when you level off at the top of a climb is too close to PPOing all the time and should not be flown at all!!! I probably should have included this caveat with my post above. Any gyro that can bite you without any provocation should not be flown at all.

Udi

[Aussie_Paul]

Even today most gyros still have a narrower gap between the best climb speed and cruise speed than a fixed wing aircraft. The sleeker we design our gyros the wider the gap. Best climb speed is the most efficient speed.

In Hybrid best climb speed is 48 to 52 kts or 55 to 60 mph and during training we cruise at 52 to 58 kts or 60 to 67 mph. Hybrid will cruise faster but more fuel is used.

Aussie Paul. :)

[mceagle]

It is interesting to read some of the posts from different people on this subject. The development of Gyroplanes in different countries has taken slightly different courses. By far the most hours flown by Gyroplanes in Australia are done by mustering pilots. Coincidentally, this section also has by far the greatest safety record - approximately one fatality per hundred thousand hours. (now two). I think this matches GA figures.
The mustering pilots did not want to loose the bottom end capability of the Gyroplane, so a lot of development went along this line.
As machines got heavier with more reliable engines it was soon found that bigger diameter rotors maintained (and even improved) the slow speed bottom end capability of the gyroplane. However there was some concern over clearance problems and drag of the bigger rotors. Clearance problems were solved with taller masts and more taxi awareness. With the introduction of McCutcheon Rotors and the newer generation thereafter, bigger rotor drag problems do no longer exist and in fact most Gyros with bigger blades were actually faster as well as maintaining or improving the bottom end.
Thus it suprised me some what when I read Doug R's article on the test flying of the Dominator Tandem with the 912. The climb speed seemed so fast and the top speed did not seem very high.
This seems to fall in line with some of the postings on this thread.

My first two-seater in 1987 (open side by side) had a best climb speed of 40 mph and a cruise speed (just off full throttle) of 50 mph. If you pulled back the throttle on climb, you would quickly get behind the power curve (35 mph)before you could level off. My last two seater was 250 lbs heavier and had larger diameter McCutcheon blades. Best rate of climb was at 40 mph and cruise of 75 to 90 mph. Cruise was limited by the sensitivity of the blades under different conditions. The cruise speed was approximately double the best rate of climb speed. You could still get behind the power curve throttleing back before levelling off. This is vastly different to what I am hearing on this thread. I would seem that most gyros are climbing at their cruise speed and that climb speed is fast enough to allow throttling back prior to levelling off.
It is interesting to note that most gyros (and fixed wings) will cruise marginally faster if the cruise speed is approached from a higher speed rather than from a lower speed.

[Brian Jackson]

...If you pulled back the throttle on climb, you would quickly get behind the power curve (35 mph)before you could level off.
I apologize for my ignorance in advance, but what does it mean to "get behind the power curve?" I haven't begun my gyro training yet but would like to be somewhat informed beforehand. Thanks.

Brian Jackson

[birdy]

Behind the power curve is when he rotor drag has increased[due to the higher AOA for slow flight] to such an extent that the maximum prop thrust can't override it and you start to sink under full power and backstick.

[gyromike]

Behind the power curve is when he rotor drag has increased[due to the higher AOA for slow flight] to such an extent that the maximum prop thrust can't override it and you start to sink under full power and backstick.

SCG, huh? :rolleyes:

[chuter]

"Behind the power curve"

My understanding is:
you have a minimum-required-power airspeed. That is the speed that requires the least amount of power to maintain level flight.

To go faster or slower than this mrp airspeed requires more power.

Any airspeed slower than the mrp is "behind the power curve".

If you keep slowing by pulling back the stick, you will reach a point at which you don't have enough thrust to just power out of it and maintain altitude, you have to lower the nose and gain airspeed before you can climb.

Just another way of saying what Birdy just said.

As usual, experts please correct me if I'm off base. :rolleyes:

[mceagle]

Doug said :-
"..and recall the article in a recent PRA mag by an Englishman flying a Cricket (a no-HS Bensen derivative with a pod and low CG). He appears to have come very close to PPO a couple of times as a result of lowering the nose after initial climb while the power was still up."
Correct me if I am wrong but wasn't this virtually a zero time pilot trying to have a go himself? If so then it is not a good example. If such was the case then it was only the forgiving nature of a gyro that saved his neck. any other field of aviation and he wouldn't have been alive to talk about it.
I must agree though that - "You really do have to tiptoe around the danger spots in the flight envelope of some of these unstable machines... even to the extent of using some awkward or seemingly wrong-headed control inputs."
I guess the problem is that beginners are not equipped to recognise the "danger spots"

[StanFoster]

Brian: Michael said it very well. I can word it a little differently but it will still be the same meaning.

As soon as I started flying my RAF..I wanted to know the MPR speed...(minimum power required).

So..I went to 500 feet above ground and kept my altimeter at that altitude. I was cruising around 70 and then just kept creeping back the throttle,,,adding more back stick..and holding this 500 foot altitude. After several small incremental power reductions and necessary backstick to hold altitude,,,I soon arrived at the lowest rpm's that sustained this altitude. I then recorded the airspeed and rpms and this is my minimum power required figure.

Any further reduction in airspeed will require more power. This is now flying behind the power curve. To take this to the extreme...as I continually slow my airspeed with more backstick...to maintain altitude...the throttle has to be incremently increased. Finally you arrive at an airspeed where the engine is screaming at full power and your altitude is still being maintained. You are now at your minimum speed to maintain altitude. Any further reduction in airspeed by applying more backstick will cause settling and your altitude will decrease.

Now...take it back to the MPR and holding altitude.... any increase in power will result in higher airspeed. So...now you are flying ahead of the power curve and the faster you go....the more power you need. Behind the power curve...the slower you go ...the more power you need.

Brian....also please note that your MPR speed will increase while you are in ground effect....as there is less drag.

Isnt this stuff interesting? :)

Stan

[mceagle]

This thread is moving so fast that I am a couple of pages behind.
Michael G #91 said :-
"My understanding is that this is not necessarily correct. The hang angle is used to center the stick to ensure there is adequate control movement available fore/aft."

Michael, my opinion is that though what you have said is essentially correct, it is because we choose the angle that we want our airframe to fly at. The rotor disc flys typically at 8 to 10 degrees angle of attack and we select the airframe angle and adjust the hang test to ensure that the joystick is in the middle of its travel when the airframe is flying at the angle we have chosen. That angle could be anything we like but most choose the keel as the horizontal flight reference line for either asthetic, efficiency or simplicty reasons. The balance (hang test) determines the horizontal position of the C of G and what we strive to achieve is normally 10 to 12 degrees nose down (measured on the horizontal flight reference line). As the rotor thrust vector is only av. 9 degrees then we have achieved the basics of a stable gyroplane (C of G ahead of the rotor thrust vector)

Re Mark #92 "Another cat among the pidgeons"
I agree with you, the propeller would tend to "straighten" the airflow over closely immersed control surfaces and would not truely represent the relative airflow. Just to what extent that would loose efficiency compared with the efficiency gained by the increased airspeed I do not know. I would like to do some such experiments in the near future to find out.

Birdy, when the MF says "Do you think this dress makes me look fat", do not answer because it is a no win situation. You will need to do some fast crawling to get out if it.
That is behind the power curve.

[chuter]

HI Tim,

Regarding the hang angle, etc; it seems to me that when the gyro is in flight it is no longer hanging from a fixed point and is free to rotate about the CG in response to various forces, so the hang angle is not so relevant.

If the thrust line is higher than the CG, it will rotate forward until the rotor thrust vector is far enough ahead of the CG to counter the PPO force. This would be an unstable configuration. :confused:

[Doug Riley]

McEagle: To clarify on the 912S Dominator, I've never posted Vmax figures. I have some apprehension that the windshield may not stay aboard at 100+, so I haven't opened it up in level flight. 90 is about the fastest I've flown. It will do more, but how much more I don't know and honestly don't care to find out. A nice cruise groove is 75-80. There's a "plateau" of airspeeds that all seem to be at or near best rate of climb; anything from 65 to 75 seems to be on this plateau. I usually pitch the props on my gyros for no-compromise climb, not cruise.

I use the machine only for training, so repeated climbs-descents represent most of its career. Once in awhile I rack it around a bit on the first flight of the day (always solo).

The deflection of the prop blast in reaction to intake direction is well known. It's a matter of adding vectors and the results are predictable. The "diluting" effect of the higher airspeed of the prop blast on AOA changes is overwhelmed by the greater lift caused by the same higher airspeed. This follows because lift is a function of the SQUARE of airspeed, while lift is only a linear function of AOA. IOW, double the AOA and you double the lift. Double the airspeed and you quadruple the lift at the same AOA. Double the airspeed and HALVE the AOA and you still double the lift.

[pwendell]

Doug said :-
"..and recall the article in a recent PRA mag by an Englishman flying a Cricket (a no-HS Bensen derivative with a pod and low CG). He appears to have come very close to PPO a couple of times as a result of lowering the nose after initial climb while the power was still up."
Correct me if I am wrong but wasn't this virtually a zero time pilot trying to have a go himself? If so then it is not a good example. If such was the case then it was only the forgiving nature of a gyro that saved his neck. any other field of aviation and he wouldn't have been alive to talk about it.
I must agree though that - "You really do have to tiptoe around the danger spots in the flight envelope of some of these unstable machines... even to the extent of using some awkward or seemingly wrong-headed control inputs."
I guess the problem is that beginners are not equipped to recognise the "danger spots"


Tim,

I believe this pilot had received a significant amount of dual instruction in the Magni trainer and had been given some transition training and received approval to fly his machine solo. But he had had very little experience in the Cricket at the time of the incident.

I think the situation in the UK now is really perverse. The vast majority of dual instruction in given in the Magni, a very stable and forgiving machine from all accounts, but, unless the student can afford a Magni, they are forced to transition to one of the few models of stabless, HTL machines that are legal in the UK. I'm sure all of here would agree that this is a recipe for distaster.

[mceagle]

Thank you for clarifying that Peter. It is certainly a recipe for disaster, self transitioning from a gyro as stable as the Magni to an unstable gyro.
Doug, isn't it a great to be able to fly a good gyro nowdays and not have any idea what the top speed is and to have no necessity or desire to find out.

[mceagle]

Michael G, even in flight the gyro is still "hanging" from the rotors, but you are correct in stating that it is free to rotate around its C of G. What stops a low Cof G machine from PPO is shift of the C of G in relation of the RTV (the more nose down it gets the further rearward the C of G gets and the more the leverage the RTV gets to lift the nose back up) and the horizontal stabilizor also supplys a nose up force, that gets greater as the nose down gets greater. The pilot himself also supplies a balancimg force by easing back on the stick, thus moving the RTV forward and supplying an extra nose-up force.
The moving forward of the RTV or rearwood of the C of G tends to supply extra lifting force to the nose and as such is a stabilizing influence against PPO tendency

[Aussie_Paul]

Tim, the trouble with what you say happens, and you are correct, is that the PPO force has to be equalled by the RTV and the stab forces. This is total wasted energy. :eek: ' could add up to quite a few litres of fuel for a musterer in a year. :D I am going for the tight a*s musterers jugular now!! :D

There is absolutely no need to have a set of forces working against another force(HTL) which can be designed out of the gyro!!!!! :(

Aussie Paul. :)

[Hognose]

As Duane [Hunn] suggested, we need something like a " Gyro Camp" several times a year where 2 or more instructors are present along with a D.A.R. and an examiner.

Tom, that's a really good idea of Duane's. Credit where credit is due. Duane is one guy I really want to meet and talk to sometime -- we have never connected at the big shows.

Spent most of today in a 172, sneaking around the pattern under the clouds, wishing the wings were rotating instead. Still, any time there's air between me and terra firma is a happy time.

cheers

-=K=-

[ben]

hey pwendell,
this is for you and i wont run from jim he's right and i dont know who is doing or did your training but either he aint right or you dont listen.

[pwendell]

Ben,

It ain't a pissing match. Just because someone wrote a procedure in a book doesn't mean it is appropriate for all gyroplanes. The important thing is to understand WHY we do, or don't do, things a certain way. Do you understand why I, and many others, believe that leveling out with full power at the top of a climb in a high thrust line, stabless gyroplane is potentially dangerous? If you do, I would be curious to know why you think it is safe.

[ben]

Ben,

If Jim told you that, you should run, not walk, away and find a new instructor. The reason for not leveling out after a climb by pushing the cyclic forward whith the throttle still on climb power is obvious to anyone who knows even a little bit about how and why gyros fly. When you lower the nose at the top of a climb, you momentarily unload the rotor allowing rotorspeed to decay. This is bad practice in any gyroplane. In a gyro with a high thrustline and no horizontal stabilizer it is a recipe for disaster. The only thing keeping such a gyro from nosing over (bunting) in normal flight is the rotor's thrust. When you push the nose over at the top of a climb, you partially unload the rotor and reduce its ability to couteract the engine thrust that is trying to push entire gyro over when it is most needed -- under full power. This is an extremely dangerous flight profile. If you are unfortunate enough to encounter some moderate wind shear or a moderate downdraft at this moment, unloading the rotor even further, your could pushover in an instant and become statistic -- a beer and a shot won't help.

Gyros are not helicopters. They do not fly like helicopters. What is acceptable in a helicopter is not necessarily acceptable in a gyro. Just because the Rotorcraft Flying Handbook describes a maneuver for a helicopter does not mean it applies to a gyro.

If you don't believe me or the other folks here, grab a phone an call another CFI. Call Greg G., Terry Brandt, Doug Riley, anyone other than Duane Hunn, and ask them.

pete,
first thing first well i must not know anything becuse that's the way i was taught to level off by my cfi jim logan i have done it many times.2)who ever told you that lowering the nose at altitude will unload the rotors is full of smellie stuff. how long you been flying these things???( and i'm the student??)3)all things that fly all level off to altitude the same exact way, a plane a gyro and yes even the helicopter that you say doesnt appy to the gyro.all of these things level off to altitude the same way, altitude,power, trim. ben

[pwendell]

pete,
first thing first well i must not know anything becuse that's the way i was taught to level off by my cfi jim logan i have done it many times.

Ben,

So the answer to the question in my previous post is, 'No'. You don't understand why I might think that leveling off by pushing the stick forward under full power at the top of a climb in an HTL, stabless gyro can be dangerous. What you do know is that you've been taught it is OK and have done it without injury, so far. You also seem to assume that I'm simply repeating things I've been told by others. I assure you that I have spent conciderable time learning why gyroplanes fly and how a gyroplane's basic design affect its performace and safety. Do I know everything about gyros? Absolutely not. Am I still learning? You bet.

I'm not interested in getting in an argument over whose CFI is right. I have explained the reasons for my position in previous posts. If you want to discuss those, I'm all ears.

It's your life up there and it is your responsibility to learn as much as you feel you need in order to be safe. You can use these forums as an opportunity to learn, or not, as you choose.

[rehler]

Ben,

I don't know about Jim Logan, your #1 comment, but as for 2 and 3:

2. Lowering your nose at any altitude will unload your rotors, but what is dangerous is lowering your nose with full power especially if it is at the top of a climb where the throttle is at a high setting.

3. No you should not level off the same with all aircraft. With a gyro, after a climb you should level off by decreasing your throttle setting - not by pushing your cyclic stick forward.

With a "typical gyro" with a high thrust line above the gyro's CG it is dangerous to make a full speed climb and push the stick forward at the top leaving your throttle set high. This can cause the gyro to quickly flip over fprward resulting in the death of the pilot. I believe that all gyro pilots should be taught to avoid this manover!

[ben]

all i ask of ya pete and ken is that you show me in any flight book where it written any different then what i have said. some people may think its wrong and teach differently and thats ok. but dont speak down about someone when he teaches the way its written. btw while im at it i have a aircommand elite CLT.

[Steven_Kozned]

Ben,

I suggest you pick up a bonafide flight manual such as is provided by every decent flight school (ie: Civil Aueronautics Bulletin #32, Fundamentals of Elementary Flight Maneuvers, U.S. Government Printing Office). Slowly pushing the stick forward while simultaneously reducing power keeps the G loading and airspeed constant while arriving at the desired altitude. This works for all aircraft.

[GyroRon]

In my dominator, I push the stick forward to stop a climb and sometimes I don't reduce power either. But I don't jam the stick forward either, just lightly and slowly press it forward

[KenSandyEggo]

Ben, there have been numerous incidents documented over the years where a gyrohead climbed at full power, left it on to the top and leveled off without reducing power and tumbled to his death. I believe it happened at El Mirage a couple years ago. Some of the old-timers here can probably give more details on how many times this happened.

[birdy]

Not sure if I should,but I'll put my 2 bobs worth in,mainly coz I'm worried bout Bens safety.
What regulates your RRPM Ben is the weight on the systm.Any change in the discs attitude will change the weight load through G forces,wether it positive or negative.
When you level out from a climb,youreduce the load on the rotors,slowing them.The faster you level out the greater the rpm loss.Even in a properly setup machine with a CLT,stab and all the bells and whistles,you can still go over if you stick forward hard enough.
A scinario that COULD catch you out is if you are leveling out ,with the power still on full ,and you hit wind shear.Your rrpm has droped slightly,your'v full thrust and the discs atitude suddenly changes to negative or 0 AOA.
If you know anything bout gyros I need go no further.

I may be a SCG Ben and have been flying for a while with alot of steep climbing and banking on full power,but I'll always backoff the power if I 'lighten the load' on the disc.

As someone said before,you can get away with it for along time,but it's not a good habit to have.