VW Gyro in Post Falls, ID.

[LAWOLF]

I am in Post Falls ID and have built a Gyro with a VW engine and a double tail with a instrument panel both of my design. The weight is 250 lbs since the tail is 1/8 thick 6061-T6 with rods to hold the tail upright and 90 degrees to the stablizer. I have also tied the rudder peddels to the tails with a steel rod through a gimble area to make the tails work in the right direction when you move the rudder peddles. I have 10 instruments on a plastic form in front with all the wiring running through the main tube to the engine area where I terminated the wiring on terminal boards. The engine has a single carb and a starter, altimeter, and a 1.6 to 1 gear reduction with a 68 inch carbon fiber 2 blade prop. The rotor is 24 feet in diameter and has a 4 foot rotor bar with two extruded 10 foot aluminum blades balanced in all directions. So some time this year I will be flying it and can't wait for the lift off. This is the first time on for me and I would like to attach a picture but I am not sure how to accomplish this task but if you send me your email I will send you a picture. My email is dlaw@hlaircraft.com :)

[Sonnyj]

Welcome aboard LAWOLF
Sounds like an interesting disign.
Gotany pics?
Welcome again
Sonny

[Friendly]

Welcome Donald

[ToddP]

Don Lives about 25 miles from me so I had some time yesterday to go over and meet him and take a look at his gyro. Don has been flying since he was 16 years old and he's a young 71 now. I've attached several pictures and hope that any comments will be constructive and helpful. This is Don's first gyro project and he's been pursuing this dream without any assistance.

[ToddP]

A couple more pics

[Sonnyj]

Thanx Don & Todd
A very nice and I mean "very"Nice Machine,looks well thought out :)
I am green with envy :D It's good to see more tallent on the forum.
Happy flying
Sonny

[GyroRon]

Hello Donald, welcome to the forum.... you couldn't find a better place to get ideas, share info and LEARN than this forum.

I have looked at your pictures of your gyro and have several concerns. But I want to first off express that I am not wanting to come off as negative in my comments and I don't want to discourage you in any way.

My first concern is the lack of proper aircraft hardware. In some of the pics I see what appears to be sloted screws holding the main airframe together! In other places I see Grade 8 hardware and in other places it is hard to tell what kind of hardware is used. In my own ship, I have used alot of grade 8 hardware, but in key areas where a bolt failure could kill me, I have used real AN aircraft hardware.

My second concern is the way your right side push tube is routed around the engines electric starter. I am about at a loss of words to describe my thoughs on this, but clearly this is not standard practice on any kind of aircraft, especially gyroplanes. If that tubes fails in flight your dead as you will have ZERO control of the gyro without both tubes staying intact. There is a way to go around that starter and not loose the strength of the tube... it is by using a scissor arm type of arrangement and it is a popular modification to gyroplanes that have things blocking the path of the pushrods.

My third concern is the modification to the control stick. As I understand it, you used a block of plastic between the stick itself and the joystick assembly under the seat. This to be honest Donald.... Scares the bejesus outta me!!! The control stick is not a area to skimp on, if it fails - just like the push tubes behind the seat - you have a complete loss of control and you die, simple as that. There has been several people killed by failures of one type or another in the control system in gyros, so this is not speculation, it is fact! My advise is to have a new stick made out of 4130 Steel and do the required bending to get it out in front of the seat where it is comfortable, but without using the plastic block as a spacer.

Other areas that concern me are not as important, but they still concern me. One is the type of blades your using. These blades have not had much of a proven record. Not saying they are bad blades, but I have read alot of negative press on them. Another thing is the complex arrangement used to move the twin rudders, I have to ask why all the linkages and levers? Why not use cables all the way to the rudders and keep it light and simple?

Now saying all that, I do want to tell you the gyro looks nice and with a little work it looks like it will be safe to fly and fun to fly. As it sits right now I would not fly it, as I fear it is very likely to have a failure in the control system and crash. I hope you do not take my post as a attack, as I would hope if you see something on my gyro that concerns you, you would tell me.

[GyroRon]

Also meant to add, that I think you need to put it on some scales, cause I can not see how in the world this will weight only 250 pounds. I estimate the weight as it sits in those pictures at, at least 325 pounds.

Has the machine flown yet? If not then do you plan to fly it sometime soon? Have you gotten any dual instruction in gyros? If so, has your gyro instructor or any other experienced gyro builders from your area seen your gyro to have a second set of eyes look it over?

You can never be too careful! Take care.....

[Screw]

Screw-In

Welcome aboard wildman. Good engine choice BTW. I too am a fan of the VeeDubb and wish you lots of good flying.

Ron is right about some of the areas of construction and don't take any of it negatively. I know this project took lots of time and hard work. Nobody, to include Ron, is nocking it. We just want you to be safe, and enjoy your machine.

Who's prop are you using? I was looking for a 2 blade adjustable prop, and I'm just wondering which one you are using.

Screw-Out

[GyroRon]

181 views and no one else thinks there may or may not be a issue with this machine? If you read all of Donalds posts, it sounds like he is going to try to fly this machine shortly. I am concerned about not only the items I listed above but also the fact that this will be not only the machines first flight, but also the pilots! I am not even sure if he has gotten or is getting any training first either..... No one else has a opinion on this?

[RICK MARTIN]

Ron, It sounds like you said it all. I agree. Just want him to be safe. The mast/keel cluster plate hardware really caught my attention, but you covered it well.

[Alan_Cheatham]

A VW powered Gyrobee, I recognize the basic airframe. There are definitely issues here that need to be addressed before flying this craft and hopefully the pilot will receive proper training as this is not a 250 lb ultralight.

[gyromike]

181 views and no one else thinks there may or may not be a issue with this machine? If you read all of Donalds posts, it sounds like he is going to try to fly this machine shortly. I am concerned about not only the items I listed above but also the fact that this will be not only the machines first flight, but also the pilots! I am not even sure if he has gotten or is getting any training first either..... No one else has a opinion on this?

I think you pretty much nailed it Ron.
I didn't notice the joggle in the control rod until you mentioned it, but I hadn't looked at all of the pictures either. :eek:

Donald, I highly recommend you have someone knowledgable check out your machine before it's first flight.
And definitely get training!

[Ralph]

Donald,

You really do need to pay attention to Ron's posts as he has your best interest at heart. The following points bother me:

(1) You cannot build a 250 pound machine with a VW engine - there is no possibility that the aircraft is Part 103-legal.

(2) Some serious redesign of the engine mount would be required to handle the weight and torque of the full-sized VW engine.

(3) The non-aircraft hardware issue is serious business.

(4) I worry about the control stick extension

(5) I think you have compromised the rotor control rod with the "jog" to get around the starter.

You should have the machine thoroughly examined by an experienced gyro pilot prior to any testing.

Ralph

[animal]

[QUOTE=GyroRon]Hello Donald, welcome to the forum.... you couldn't find a better place to get ideas, share info and LEARN than this forum.


Other areas that concern me are not as important, but they still concern me. One is the type of blades your using. These blades have not had much of a proven record. Not saying they are bad blades, but I have read alot of negative press on them.

Ron Not sure which blades he has, but I have the Vortech 12 foot blades on my scorpion-162, after getting intrested in that RH-2 falcon gyro on vortechs web site, I called Neal at Rotorhawk, and had a long talk with him, he is a really great guy and will answer any questions a person would have.
Anyway I asked him what he knew about the Vortech blades,Since Vortech also sells his Rotorhawk kits for him, and he informed me the Vortech bladees are his. I figured there was a connection,since when we got a set of vortech blades for the guy in pa. that bought the dusty2 prototype, the box had Rotorhawk on them.
now to the blades them self, at first you had to assemble the spar inside your self, in the plans they showed to be glued in with J-B weld, but also they need to be pinned inside so they can not come back out ( ask mike gibson about that one) anyway neal now installs the spar him self when he sells them. so far i have not heard of any failures other then the spar slideing out when not pinned. I am still going to try and fly my blades but keep a close eye on them.Neal did say a guy in canada did a bounch of tests with them on an Exec,helicopter,and he has all the report info somewhere.
what I do know is they really are a slick high lift blade. they have been out for years under the Flec name. so anyway anyone thats out there flying the Rotorhawk blades let us know what you think about them.
Oh and of cousre I learned that RH-2 on the vortech web site is a one of a kind that a guy built with a 4130 airframe, Neal owns it now.

after learning more about the fact I will have a problem getting an FAA examiner to check me out in my Scorpion, I may be going for a nice gyro my self soon., I mean sure my business partner is a helicopter CFI.but if i can only get soloed and not really legally fly it anywhere, then the Gyro looks better everyday. btw Ron didn't you have one of those RF-150'2 when i first met you? and what did you think of that machine? Neal makes the Kits for those also. I am kind of leaning that way since maxie doesn't sell kits for his 2 seat Mad Max gyros anymore.
anyway just thought that was some useful info to pass on about the blades.

fly safe ya'll

Tim H.

[GyroRon]

I recieved a email from Donald and wanted to reply here to a few of his points.

It seems he believes the hardware he used is stronger than aircraft hardware. This could very well be true. Most aircraft hardware is equal in strength to grade 5 hardware. The difference though is that aircraft hardware will NOT lose it's strength if it is bent. A harder bolt, such as Grade 8 hardware or stainless - which Donald said he used - Is stronger, or harder if you want to use that term. But the harder bolts will SNAP if bent too far, and they lose a large portion of their strength if bent at all. If you price decent grade 8 or stainless hardware to aircraft hardware, there is not a huge price difference, And therefore there is no good reason not to go with real aircraft hardware. This isn't a gokart, this is..... anyone......???........ A AIRCRAFT!!! use the right stuff!

Also Donald did not respond to the comments about the Plastic stick extension under the seat. I am not sure what his thoughts are about that. Again this is a big no no in my book. Most experienced gyro pilots know the importance of a strong stick and control assembly. Most of the older wiser gyrohead will go out of their way to replace a aluminum stick with a steel stick to gain additional strength. Alot of us will upgrade to larger diameter push tubes to gain additional strength. I know that piece of plastic is pretty tough stuff, and it will be hard to break it, but this will surprise me if this plastic fitting does not cause a problem at some point where there is a lose of control of this gyroplane.

The jog in the pushrod to allow it to clear the engines starter.... Donald described how he made this jog very beefy. I still don't feel all warm and fuzzy about it. It just seems like a major weak link in the control assembly.

I think if Donald did more research into what kind of problems have lead to fatal gyroplane accidents, he would feel more along the lines of how I feel about these two very unusual modifications to the control system.

I do want to add that Todd Powell has seen this gyroplane in person. He didn't like these items either. He did not want to upset the owner, his hope was if ore of the experts here could see these pictures, possibly enough comments could be posted that might sway Donald into making a few changes that would help insure his safety in this machine. It was also my understanding that Donald has gotten ZERO gyroplane instruction and he is planning to fly this bird within the next month or so.

Donald is on the other side of the USA. I have nothing to gain and nothing to lose if he crashes and burns. But I would hate knowing that a accident could have been prevented by making a few simple changes to the gyro and going to a gyroplane instructor and taking at the absolute least, a hour or two of training.

Can you imagine never having a momment of gyroplane flight training or experience.... and then hopping in a unproven, highly modified, gyroplane that clearly has some issues that worry not only several experienced gyropilots, but also the designer of the Gyro Kit that this gyro was based on!!!

I am glad we got another spunky gyrohead wanting to go gyro flying. I am glad he is willing to think outside the box in design and modifications. I am also glad Todd has a neighbor so close to fly gyros with. But I am very fearful that if Donald does not rethink his plans on flying this machine as it is and with no training, he is going to end up hurt or worse.

Of course we all are hurt if something happens, cause to the rest of the aviation community, this would be just another gyroplane crash and would further reinforce the notion that were all idiots to fly such dangerous machines.

Donald, I beg you to rethink your plans and let Todd or someone else in your area - John Landry would also be good - go over your machine and help bring it up to accepted construction standards for gyroplanes. And go see the guys at Sportcopter or Randy Coplien or whoever else is close by for at the very least a hour or two of training. If you are a good stick then that may be all you need, but on your madien flight in your own unproven machine is a bad time to find out you can't handle your machine. There is several modes of flight in a gyroplane that can kill you and are unrecoverable from. Your machine has a HTL and a powerful engine, it can PIO and PPO very easily. Do you know what these are? Do you know how to avoid these?

[scottessex]

This is the first time i have seen the pics, I too express concern over the same items, Especialy the non-aircraft hardware at the cluster plate. I have never seen slotted screws that have a shank on them. Even if these are stainless, having a non-shank bolt in an area like this is a bad thing. If the bolts are threaded all the way, the threads are going to saw the aluminum rather quickly.
I wonder too about the pushrods binding when aircraft weight is suspended from the rotor.
I understand Your enthusiasm, and wish You the best, But please take the constructive critisism to heart, and make a few minor changes, and you will not regret it.

[animal]

I recieved a email from Donald and wanted to reply here to a few of his points.


Also Donald did not respond to the comments about the Plastic stick extension under the seat. I am not sure what his thoughts are about that. Again this is a big no no in my book. Most experienced gyro pilots know the importance of a strong stick and control assembly. Most of the older wiser gyrohead will go out of their way to replace a aluminum stick with a steel stick to gain additional strength. Alot of us will upgrade to larger diameter push tubes to gain additional strength. I know that piece of plastic is pretty tough stuff, and it will be hard to break it, but this will surprise me if this plastic fitting does not cause a problem at some point where there is a lose of control of this gyroplane.

The jog in the pushrod to allow it to clear the engines starter.... Donald described how he made this jog very beefy. I still don't feel all warm and fuzzy about it. It just seems like a major weak link in the control assembly.

I think if Donald did more research into what kind of problems have lead to fatal gyroplane accidents, he would feel more along the lines of how I feel about these two very unusual modifications to the control system.


Ron you are so right about control forces,after 4 test run up's of the Scorpion, I noted one of my bell cranks I made flexing,also the bolts my control mixer slides up and down on had already looosened some. needless to say I have already taken it apart and made a new bellcrank from steel, and i am redesigning the slider bolt mounts.
people just don't realize what pounding control rods and linkages take when everything is spinning.

Donald,please look into makeing a scissor link, it is not hard to make and is proven design. in your case to make it clear you could make it like 2 teetering beams one above and one below, so as to when the rod pulls down on the back end of the bottom beam it will push up on the front end, then in turn will push up on the front end of the top beam, which would then pull down on the back of the top beam. hope this helps ya out some. I designed my own helicopter and was swinging a set of blades that weighed 40 pounds each, beleive me I can tell you about parts breaking.

[Doug Riley]

A VW engine will not last any time at all at 5K. In fact, it will not last above 3K without a large oil cooler (not the tiny one that comes on the car; that one works only because it has fan-forced air and a much more conservative duty cycle than we face in an aircraft).

I made a bunch of unscheduled landings in my VW gyro years ago to gather this information. One such stop was on a suburban residential street. Somehow I didn't hit any mailboxes (or the stop sign at the end of the street) with my blades. Another was on the grounds of Green Haven Maximum Security State Prison. The staff came out to make sure I wasn't staging a Hollywood-style bust-out, then drove off. I suppose today the consequences would be more serious.

It is virtually impossible for a person, however smart, to modify a gyro successfully to this extent without a great deal of specifically GYRO experience and some background in design. For the 14 or so years that I ran AEROTEC and sold Gyrobee kits, I had to preach this truth to unreceptive ears over and over. Invariably, those who didn't listen would call up sheepishly months later, having crashed a time or two, admitting their errors and pledging to stay stock until they had more experience. By sheer luck, none of these well-meaning but unqualified "designers" died in the resulting crashes. All of them lost a lot of money, time and emotional energy. They also lost a few square inches of skin to runway rash as their machines self-destructed.

To take just one thing, most people who attempt to "imagineer" a gyro do not grasp just how critical weight is in a rotorcraft. It's just about twice as critical as in a small FW craft such as a Cessna. Why twice? Unlike a wing, a rotor produces produces a pound of drag for every 4-4.5 lb. of gyro weight (for an inefficient plane, the ratio is more like 8:1). The Gyrobee was designed with this very much in mind. It isn't any stronger than it has to be in order to function adequately as a 250 lb. gyro. The G-B frame is in no way adequate for a machine that weighs over 400 lb. empty, as this one most definitely does.

The extra weight degrades performance (especially climb, a safety item) to an extent that's astonishing until you get used to it.

Teaching yourself to fly in an untested gyro (or even a tested one) is absolutely a recipe for disaster. Things simply happen too fast for anyone to "think through" what to do next. The machine is already on top of you on the pavement while you're still thinking. Control inputs MUST be reflexes. The reflexes must be developed in a controlled, safe environment. Both takeoff and landing are far different than in conventional craft. No one is born knowing how to do them, and "I'll figure it out as I go along" is not a viable option.

[GyroRon]

Call me quick to give up, but I give up. I got two more emails from Donald this early afternoon. In one email he clearly states he has no gyro flying experience and no gyro instruction and he DOES intend to fly this thing as it and he is. He is also sure of his modifications and hardware choice and from the tone of his emails, he is not going to change those items either.

He also says he weighted this gyro and it was infact 250 pounds with fuel on board. He says this is possible because it has a lighter twin aluminum tail instead of the heavy fiberglass tails normally used on this ship. What do I say?..... BULL$hit! The following componets easily add up to more weight.
1. Engine and redrive = at least 180 pounds
2. Warp Drive prop = at least 10 pounds
3. exhaust and oil cooler = at least another 10 pounds
4. Rotorhead assembly = at least 10 pounds
5. Rotorblades with hubbar = at least 65 pounds
6. Wheels and tires = at least 10 pounds
7. instrument panel with gauges = at least 10 pounds
8. seat tank with NO fuel = at least 3-5 pounds
9. control rods and underseat assembly including stick = at least 5-8 pounds
10. Twin aluminum tails with bellcranks and pushrods = at least 10 pounds
11. basic airframe structure = at least 25 pounds
12. additional braces and motor mounts and seat bracing etc... = at least 10 pounds

So the way I add it all up his gyro has to weight at least 350 pounds and more likely it is closer to Dougs guess of 400 pounds. He has N numbers so that is not the issue - of it being a legal ultralight - but it is heavier than the basic gyrobee airframe was designed to be operated at, that and the fact that if Donald can't even figure out it weights more than he thinks it does, then how can he know if his modifications will really be safe to fly? Hell why get N numbers for a ship that weights under 254 pounds?

Anyway, He sounds like he is on a mission and it wouldn't matter who trys to advise him, he isn't going to listen cause he knows more about it then you do. How he made it to 70+ years old with this mindset is amazing. I wish him alot of luck.

[Doug Riley]

Here are a few numbers (i.e. not opinions):

5000 crankshaft RPM/1.6 redrive ratio = 3125 prop RPM

Circumference of 68" prop = 68/12 x 3.14 = 17.79 ft.

3125 RPM/60 = 52.08 rev/sec.

Prop tip speed = 52.08 x 17.79 ft. = 927 ft./sec

This tip speed is deep in the transsonic range and is far in excess of what should be tolerated. A similar prop on a Rotax with 2.58 gearbox would have a tip speed of 747 ft./sec. Even that's high. Such a Rotax on a gyro would more typically run a prop of 60" diameter, with a tip speed of 660 ft./sec.

The tip speed and prop RPM will actually be higher than the static tests indicate. As the aircraft begins moving through the air, the load on the prop decreases and it will spin a bit faster. The tips may actually go supersonic, at least on the curved side.

I don't know if a Warp Drive will hold together under such conditions. It's certainly not how it was designed to be used.

[PW_Plack]

It's frustrating to warn someone unsuccessfully, and it's also frustrating when a crash follows, because that does affect us all. I think, though, that it's time to wish Donald the best, pray that his first crash is humbling but not fatal, and stay on friendly terms so he comes back to the forum before attempt #2.

Unfortunately, for that to happen, we have to hope the VW throws a rod before any of the control or airframe stuff breaks...

[Doug Riley]

With or without blades?

[GyroRon]

With or without blades?


Don't know but it would nice if all the FAA inspectors used these scales! A lot of Illegal ultralights would become legal all of a sudden!!! :D

I just don't see how it is possible for it to weight that little. :confused:

[Brian Jackson]

I couldn't really tell from the photos, but I'm curious of the plackards on the front of the mast tubes are glued on or screwed into the tube. If screwed, I'd be wary of a weak area, and if glued, what happens if it becomes delaminated and goes through the prop? I don't know, but what is the accepted practice for attaching these? Thanks.

Brian Jackson

[Brian Jackson]

Another thing I noticed, besides the notes on the attached image, was that the rudder "rod" only exists on one side of the airframe, meaning that it's meant to act as a push-pull rod. For the forces required, I don't see how this rather thin, unsheathed rod will keep from bending under compression loads.

EDITED: Oops, I just noticed it was a sheathed push-pull cable. My mistake.

[automan1223]

If you think you feel bad now, I can tell you from 1st hand experience. It sucks to put together a machine that will no fly as intended. I have been working on gyros since 1998.

I cannot add anything to the technical points except aircraft hardware does not use threads thru the material that is being secured. AN hd has a grip length. the threads are not in any way thru the material.

The rest of the machine, and I know this is gonna hurt but I have to agree with all the other guys here. Is a perfect example of great intentions that will get you killed in short order. Case closed. Take the engine and rotor head off and cut up the airframe cause I know you have not drilled a single hole as per aircraft specs, drill, ream, measure, used an rated hdw. I dont know where to start but you have to stop before you get hurt or worse.

If you are lucky you will end up only losing your pride and a few scrapes and bumps. Please do not let us read about you in the funny papers.

no training ? go ahead and throw the keys to some 16 year old and see what your vehicle will look like when you get it back. And that stays on 4 wheels, (hopefully)

Sincerely,
Jonathan Weis
Oriental NC

[brett s]

Hopefully when the mast departs (and it will with the hardware used, it's just a matter of when) it'll be long before it gets in the air...and there's no way that thing really weighs 277 lbs given the configuration. Definitely a Darwin Award candidate if he still attempts to fly it even after all of the great advice here, some people are apparently determined to kill themselves.

[Brian Jackson]

On another note, isn't the GyroBee designed for a 60" prop? In it's documented configuration it's about 1" from CLT. With a 68" prop it's going to be at least 5" HTL, perhaps more with the added weight below the prop TL. Granted there's plenty of HS there where it needs to be, but nearly half a foot HTL would make me feel uneasy, especially without any training or testing. An experienced gyro pilot, from all I've read and learned here, might be able to handle such a configuration. But as was stated earlier by Doug Riley, we're not born with these reflexes. To risk life and limb just because you're "damned determined" is definitely a precursor to a Darwin Award for sure.

[Hognose]

I am in Post Falls ID and have built a Gyro with a VW engine and a double tail with a instrument panel both of my design. The weight is 250 lbs since the tail is 1/8 thick 6061-T6 with rods to hold the tail upright and 90 degrees to the stablizer. I have also tied the rudder peddels to the tails with a steel rod through a gimble area to make the tails work in the right direction when you move the rudder peddles. I have 10 instruments on a plastic form in front with all the wiring running through the main tube to the engine area where I terminated the wiring on terminal boards. The engine has a single carb and a starter, altimeter, and a 1.6 to 1 gear reduction with a 68 inch carbon fiber 2 blade prop. The rotor is 24 feet in diameter and has a 4 foot rotor bar with two extruded 10 foot aluminum blades balanced in all directions. So some time this year I will be flying it and can't wait for the lift off. This is the first time on for me and I would like to attach a picture but I am not sure how to accomplish this task but if you send me your email I will send you a picture. My email is dlaw@hlaircraft.com :)

Don, here's what I like and don't like.

Like:
idea of your gage cluster. Not sure about layout, but it's innovative alright
running wiring through keel. Good idea but may cause some hair-pulling on maintenance
Tail concept, BUT. Two questions -- (1) why not use sheet, it'd be much lighter, and (2) have you figured the air loads on this?


Don't like:
Non-AN hardware. There is much, much more to hardware than tensile strength. Entire books have been written on mechanical fasteners. Using automotive or hardware fasteners leaves stress risers in places you don't want them. The AN bolts are designed to have no stress risers near the head. SAE hardware threads are normally cut, not rolled, and unlike AN fasteners, a wide range of variation is permitted. Also, while as many as half of "Grade 8" bolts in hardware store bins are Chinese counterfeits, a box of AN bolts comes with a pedigree. Some other differences:

corrosion resistance.
Material. SAE Grade 8 bolts are mild steel. AN fasteners are usually nickel steel.
ductility. AN bolts are more ductile. SAE Grade 8 is the opposite of ductile, which is: "brittle."
load bearing in shear. SAE hardware is threaded right up to the head. AN has a shank to fit the appliction. This makes shear loads very hazardous for any SAE bolt (including Grade 8).
thread manufacture. SAE threads, as I mentioned, are cut. AN are rolled. This means that the grain of the material is cut through on SAE bolts, weakening them. What's more, the threads are cut AFTER heat treating, so sometimes the heat treatment is cut clean through.
consistency. AN fasteners are subjected to more rigorous quality control and exhibit less variation in measurements and mechanical properties within, and especially between, batches.

With the larger, heavier VW motor than the customary lightweight 2-stroke engines on a gyro in this class, your Gyrobee-based frame is badly underbuilt. Look at the design of the cluster plate on any of the gyros that is successful with a heavier engine. You will see that they are trapezoidal or an irregular 6-sided shape something like a trapezoid, that spreads torsional loads over a wider area on the keel. Your version may not hold the mast in torsion.
Struts and braces. They are fine and good, but they transmit loads. How much, and where? If you can't answer these questions you may have transmitted a load to something that will break.


Finally, a few words about the Teach Yourself Gyro method. That was once the most common way to learn. The survivors became good gyro pilots. Many of them are instructors themselves now, and they became instructors in part because they got sick of burying friends. When you train with one of these worthies, you can do something wonderful: you can learn from his experience so you don't have to learn from your experience.

There's a saying: "Good judgment comes from experience. Experience comes from bad judgment."

There is probably somebody on this earth who starts grinning when he or she sees you coming -- even if it's just your dog. You've shown you can work with your hands, now set your ego aside and work with your head, so that those smiles will keep coming for many more years.

You might be a little ticked at Ron Awad right now, but he has given you the best advice you are going to get in your life, because it's advice that can keep you alive and healthy. If you choose to take it. Ron has the rep on this forum as the guy "who'll fly anything." If he says he wouldn't fly your machine without making some changes, it would behoove you to take some notes.


cheers

-=K=-

[animal]

www.vortechinternational.com/review.html
www.vortechinternational.com/fag.html
www.vortechinternational.com/article.html
www.warpdrive.com
www.greatplainsas.com/screddr.html
The best is the article at Ken Brock on the KB-2VW and the weight of the gyro which is 312 lbs with a 9 lb tail and a wooden prop, also another gyro kit KB-3 with a Rotex engine single tail wooden prop is 250 lbs, another model is with a KB-2 McCulloch engine weight 250 lbs with a single tail.
Performance top speed
KB-2 McCulloch 90 to 95 mph 2 cycle engine oil added
KB-2 Rotex 63 to 70 mph 2 cycle engine oil added
KB-3 VW 1835 cc engine 90 to 95 mph 91 octane gas
All these engines are mounted on a very same frame and all have very good reports on flight. and have no reported problems I can find.
My gyro LAWOLF has carbon fiber prop 3 lbs and a aluminum double tail so if I wish to mount a cab the tail will not be blocked and the weight is 3.8 lbs the gyro blade is an extruded aluminum 24 foot diameter and the weight is 30 lbs with the 4 foot extension bar. its weight with 4 qts of oil and two galions of gas is 277 lbs. The oil is 2 lbs/Qt since I have a oil cooler. I am lighter than the KB-3 but I have to fly it with all the new conversions to see if it handles correctly with the lighter equipment along with the ability to air start with a alt and starter.

Donald did you assemble the Blades your self? up untill lst year they came where you had to install the Spar your self,now they are sold with the Spars installed. anyway the reason I ask is make sure you have the Spar Pinned if you did it your self. I know of one gyro that was flying these blades and the spar slid out about 6" luckily the guy made it down ok, this was told to me By Neal of Rotorhawk. Vortech blades are his Blades, he now installs the spars before shipping. I also know of a Scorpion that after 25 hours had cracks in the blades, was later totalled when the spar came out of his vortech tailrotor blade.
so just be careful, I say this becouse I have Vortech blades on mine also,needless to say I check mine after everytime I run them up.
fly safe,we all want to see ya around and get to meet ya in person at the fly ins.

[Brent_Brown]

FYI you do not have a KB frame

[Brian Jackson]

Good for you, Donald! I know you said "no more comments", but I just had to say I'm very, VERY glad that you're getting together with Todd on this. He'll be able to help you quite a bit. We all just want you to be as safe as possible... It's a brotherhood here, and we look out for our own.

Respectfully,
Brian Jackson

[Tom Evans]

Donald, If you truly do not understand what concerns others have with your build and hardware, I suggest you reread those posts, or have someone read them to you so you can hear those same words with your ears. Maybe then it will sink in. I am more of a self trained engineer than a gyroplane expert, but to my mind, all those points that have been pointed out are valid. And by the way, why do you suppose AN hardware was developed?

[GyroRon]

You don't want a hard bolt, cause a hard bolt is also a brittle bolt. Softer bolts will give before they break and the Aircraft bolts - AN hardware - is made to be able to bend 90 degrees in one direction and still be as strong as it was before it was bent. Harder non aviation bolts would snap if bent 90 degrees.

Don, I am also very happy you will let Todd help you sort out the couple issues with your gyro.

I myself will personally pay for one hour of dual instruction for you if you will go get it - just email me after you have gone to the instructor and I will send you a check priority mail. Just please send me a reciept

I like your ideas and your willingness to try to experiment. I hope one day to meet you and shake your hand and watch you tear up the sky in your gyro. I think you will do good now that you have a open mind.

I know we all haven't seen your gyro in person, but a picture is worth a thousand words! I am sure if I posted pictures of a indy car for you to look at, if there was something wrong with it, you could point it out just by seeing the picture.

Good luck and hope that all works out for you.

[BUD ONEAL]

Two things come to mind,Herb Cox and Bill Parsons, Both killed by control system failuer
These two men had many ,many hours in the air in gyros. except for rotor blade or control rod failure most every thing else will call for unplanned landing.Except if a engine should deciede to leave its mount. Ron is right all my bitching to him was not in vain.As Ron said,Just my two cents worth!
Bud O'Neal

[LAWOLF]

Donald did you assemble the Blades your self? up untill lst year they came where you had to install the Spar your self,now they are sold with the Spars installed. anyway the reason I ask is make sure you have the Spar Pinned if you did it your self. I know of one gyro that was flying these blades and the spar slid out about 6" luckily the guy made it down ok, this was told to me By Neal of Rotorhawk. Vortech blades are his Blades, he now installs the spars before shipping. I also know of a Scorpion that after 25 hours had cracks in the blades, was later totalled when the spar came out of his vortech tailrotor blade.
so just be careful, I say this becouse I have Vortech blades on mine also,needless to say I check mine after everytime I run them up.
fly safe,we all want to see ya around and get to meet ya in person at the fly ins.
Yes they came with the insearted spars and the plastic end caps. I drilled the blades and balanced the blades both ways cord wise with the SS traps on which Souza sent to me and measured from the front the exact distance to the strap edge on both blades then I also placed the level piece of aluminum under the top strap to make sure the straps are flat to each top and bottom and then drilled the first hole through the 25% cord hole and placed in a bolt to make sure the align is correct. Then I installed the hub bar which already has the pitch cut in the bar and then pulled a string from the trailing edge of one blade to the other trailing edge of the other and made sure the string crossed the center position on mark above the tetter bolt block. Then I clamped the straps solid and drilled the balance of the holes and placed bolts in each. I then repulled the string to check the alignment again. The balanceing I made gigs to hold the blades by placing a small tube in each of the 25% cord hole both ends with the blated installed. Then balanced cord wise and then reassembled every thing and then placed the tetter bolt in the hole and placed it on another gig I built to accept the bolt and placed the total unit on the tetter bolt. Then I balanced end to end wise and it took a very small piece of lead on one end which i secured inside the blade with two tube bonding cement. I also secured all the other weights with the same bonding cement. The blade is now ballanced cordwise and lengthwise. I torqued the blade bolts to the exact torque requred for the bolts after I oiled the area where the nut will come in contact with the aluminum and brought the torque down in steps in a fassion as you torque a head on an auto engine. I then placed the plastic end caps on the blades and secured them with the same bonding cement. I then put a small roll pin in the area to secure the plastic end caps. HAVE I FORGOT ANYTHING ??

[BUD ONEAL]

Yes Don, you have, See sportcopter or call Ernie Boyette for a set of rotors that are built right,balanced and test flown before you get them, Then you will know that it is not the rotor blades that killed you.

[LAWOLF]

FYI you do not have a KB frame
No I downloaded the frame of a Gryobee of which I used. The only difference I could see in the KB frame and the Gyrobee frame was the height in the upper strut. I looked at the thrust line of the Gyrobee and placed a point on where to make the thrust line on the upper strut with a VW engine with a gear reduction which moves the position of the prop from the crank area to 6 inches above the crank and distributes the load of the prop on the blacket and bearing of the gear reduction unit.

[skyguynca]

Actually there are a great many difference in the KB2 and the Gyrobee, I have built and flown both. The cluster plates are different, the nose gear is different and the support bracing for the mast both engine side and pilot side is different. On the KB2 the mast and engine bracing are all on the same side and it is a combination of 4130 angle and 6061t6 angle and no bracing on the front side also the cluster plate is 6061t6 at 1/8 in thick and a larger trapizoid shape to spread the load from the mast keel junction over a larger area. The Gyrobee uses front mast braces that the seat also attaches to, and aluminum angle for the engine bracing since the engine only weighs 95lbs without exhaust and starter. The cluster plate on the gyrobee is stainless and matches the width of the tube so it is point loaded (another reason the right hardware is important in that spot) The KB2 with a VW or Mac uses a much shorter prop and wider prop while the gyrobee was designed with the 447 and uses a much thinner and longer prop, the thrust lines are in different places on each machine and the seat height is different on each machine.......there are a ton of differences and each important to that design. The Gyrobee frame was never designed to handle the weight of a VW while the KB2 was and the listed difference above demonstrait that easily.

[LAWOLF]

You don't want a hard bolt, cause a hard bolt is also a brittle bolt. Softer bolts will give before they break and the Aircraft bolts - AN hardware - is made to be able to bend 90 degrees in one direction and still be as strong as it was before it was bent. Harder non aviation bolts would snap if bent 90 degrees.

Don, I am also very happy you will let Todd help you sort out the couple issues with your gyro.

I myself will personally pay for one hour of dual instruction for you if you will go get it - just email me after you have gone to the instructor and I will send you a check priority mail. Just please send me a reciept

I like your ideas and your willingness to try to experiment. I hope one day to meet you and shake your hand and watch you tear up the sky in your gyro. I think you will do good now that you have a open mind.

I know we all haven't seen your gyro in person, but a picture is worth a thousand words! I am sure if I posted pictures of a indy car for you to look at, if there was something wrong with it, you could point it out just by seeing the picture.

Good luck and hope that all works out for you.
You have made a statement but can you guide me to a site which I can verfy the data or send me the data on this statement. I have gone to a site www.arp.com and others which indicate that grade 8 is better than AN bolts but I am placing the 8 SS bolts I have in the strap which holds the upper tubes to the lower frame tube with AN bolts even though I have placed another 1/4-28 grade 8 bolt in the middle of all these SS bolts. The strap in question is securred to the upper tube with 4 10-32 SS bolts by the drawings but it now has another bolt in the middle 1/4-28 and will have the 4-SS bolts replaced with AN bolts. I still would like to have supporting material to support the statement you have made from a bolt manufacture.

[Doug Riley]

This business about the hardware really needs to be cleared up. The SAE Grade 3 hardware specification calls for 110,000 psi tensile strength steel. The Air Force-Navy spec (AN) is for steel with 125,000 psi tensile strength. SAE Grade 5 calls for 120,000 tensile psi steel. All these numbers are for the smaller diameter bolts that we find in gyros.

Tensile strength is only the beginning of the story. Most bolts in our airframes are loaded in shear. Steel alloys of the sort used in bolts have a shear strength that's only about 70% of their tensile strength. Thus the loading charts that turn up in aircraft design books give a maximum shear load on small AN bolts at about 80,000 psi. Of course, the SAME reduction when converting from tension to shear must be made with the weaker SAE Grade 3 bolts, too. One must compare apples to apples.

What's more, the tensile strength spec is "ultimate" tensile -- the load at which the material breaks (UTS). It stretches permanently at well below the UTS load level -- in fact, at the load level corresponding to its "yield tensile" strength (YTS). YTS for 125,000 psi UTS steel is a bit over 100,000 psi. That, plus the fact that a bolt with rolled thread "necks down" to its minor diameter, accounts for the recommended tensile load limits for AN bolts. Again, all these reductions in apparent strength must applied across the board to SAE bolts, if an honest comparison is to be made.

If you do this, you'll find that AN bolts are very slightly stronger than SAE 5 bolts, and about 13% stronger than SAE 3's.

The superior design detail, good plating that doesn't rust in a month or two, short thread length (to allow true shear use) and lower incidence of fakes*
make AN bolts the sensible choice for aircraft.

* "Lower," not zero! Warch for fake AN's as well. Rockwell, California Screw (CS) and Aero are good brands. The manufacturer's ID is stamped on the heads of AN bolts.

[LAWOLF]

Actually there are a great many difference in the KB2 and the Gyrobee, I have built and flown both. The cluster plates are different, the nose gear is different and the support bracing for the mast both engine side and pilot side is different. On the KB2 the mast and engine bracing are all on the same side and it is a combination of 4130 angle and 6061t6 angle and no bracing on the front side also the cluster plate is 6061t6 at 1/8 in thick and a larger trapizoid shape to spread the load from the mast keel junction over a larger area. The Gyrobee uses front mast braces that the seat also attaches to, and aluminum angle for the engine bracing since the engine only weighs 95lbs without exhaust and starter. The cluster plate on the gyrobee is stainless and matches the width of the tube so it is point loaded (another reason the right hardware is important in that spot) The KB2 with a VW or Mac uses a much shorter prop and wider prop while the gyrobee was designed with the 447 and uses a much thinner and longer prop, the thrust lines are in different places on each machine and the seat height is different on each machine.......there are a ton of differences and each important to that design. The Gyrobee frame was never designed to handle the weight of a VW while the KB2 was and the listed difference above demonstrait that easily.
Thanks for the input, what you can not see is that I have the upper plates which hold the gyro head are double 1/8 inch 6061-T6 on each side of which makes the plate 1/4 inch thick and gives the area support over two plates additional. The plans indicate only one plate on each side. The bottom plate which holds the upper tube to the main frame is Stainless Steel 1/8 inch thick and has four AN3-27A bolts and one additional 1/4-28 grade 8 bolt now. I will replace the total of 8 SS 10-32 bolts to 8 AN3-27As when they arrive. The 1/4-28 will remain. The thrust line will be the same as the gyrobee thrust line since the engine has a gear reduction unit which moves the prop 6 inches up towards the gyro head making the thrust line the same position on the mast. I hope it works but when I take off a little of the runwy I will only fly a few feet high and will see it the thrust line is right if not I will land. I will practice take off and landing many times before I try to make it around the pattern.

[Brian Jackson]

...The thrust line will be the same as the gyrobee thrust line since the engine has a gear reduction unit which moves the prop 6 inches up towards the gyro head making the thrust line the same position on the mast. I hope it works but when I take off a little of the runwy I will only fly a few feet high and will see it the thrust line is right if not I will land.
Donald,
I am so relieved that you are keeping an open mind to some of the things we've pointed out these past few days. You're a man to be respected for that, as many others whom have turned a deaf ear to reason have paid the ultimate price. With Todd's willingness to help you, and some very simple mods, I think you'll end up with a very fine ship, and spend many joyous years flying her! :)

One thing I did want to mention however, is that "Thrust Line" and "CLT (Center-Line Thrust) are not the same thing. Your thrust line will always be at the hub of your prop. Moving your prop up 6" raises the thrust line 6". Now, CLT refers to the relationship between the thrust line and the center of gravity of the entire "full-up weight" of the ship. This includes the weight of the pilot as well. Hypothetically, with all other variables being equal, your machine is now at least 7" HTL (high thrust line), depending on how much weight exists below the thrust line. When you moved the prop up 6" you also raised significantly where the pushing force will be applied to the airframe in flight. The higher this thrust line, the more susceptible you are to PPO (powered push-over), which is an unrecoverable phenomenon.

But as you've probably read, there are numerous remedies to correct for this, and it might not be expensive at all, just a simple modification (I read in your post that you're on SS).

But to reiterate, hats off my friend for your courage to explore some simple, cheap fixes that will ensure you and your family avoid tragedy. You won't regret it. And please keep us all posted. You've got a fine ship and we'd all love to see it fly... safely! :)

Respectfully,
Brian Jackson

[Mayfield]

Don,

I'm very glad to see that you decided to stay in the group and calmly discuss your project.

Although we, as a group, sometimes come off as "know it alls" that is not really the case. There is a tremendous amount of gyroplane specific knowledge available here.

I suspect that many of us have seen almost every conceivable gyroplane incident/accident. Over the last 20 years or so the gyro community has come up with ideas that have the potential to improve safety a lot.

As a group, we have begun to have a pretty good handle on stability and control, structure, performance, rules and regulations, etc.

Like any group, we have squabbles. In the end, we all learn by exchanging info. I am very pleased to see you posting about your project and attempting to learn what you can.

As I'm certain you have realized, gyroplanes are substantially different than all the other things you have flown. I took me many years to really understand that fact.

I fly airplanes, helicopters, and gyroplanes. I have made my living for the last several years flight testing. What has continued to astound me is that a gyro can be made to leave the ground and fly with a misalignment of forces that would be impossible with a fixed wing or helicopter. Unfortunately, this means that we can "fly" gyroplanes that are incredibly unstable and get away with it most of the time.

Anyway Don, thanks for joining this group. My unsolicited recommendation is to believe that just about everyone here will try to help as much as possible. Critiques of your project are not attacks. I know that is sometimes hard to believe, but it is true.

Again, welcome

Jim Mayfield

[PW_Plack]

Don,

The exact numbers may be a little "iffy," but it's hard to argue that small planes are more dangerous than airliners per hour, and they certainly are more dangerous per passenger-mile. Groen Brothers, who are trying to market a big, commercial gyroplane to law enforcement and other industries, did their own study which found gyroplanes had an accident rate 23 times that of general aviation. They believe the accident rate is a big reason they can't close deals.

Insurance companies love nothing more than writing policies and taking our money, but even they conclude gyroplanes are very high-risk machines.

Sadly, the reasons for this have been known for a while. The two big ones are stability, most specifically pitch stability, and lack of pilot training. Some of the most alarming deaths in the past few years have involved retired airline captains. One had over 20,000 hours in jets, and had recently been signed off to solo his gyro.

The sentiment you feel coming through in the comments here on the forum is not personal hostility, it's just frustration. Everytime someone crashes a gyroplane, it furthers the bad image of gyroplanes in general. It makes airport managers think twice about allowing them on-field, discourages insurance companies from offering coverage, and makes our families pressure us to give up the sport we love.

If the guys here come across as a little crabby, it's because they see you repeating some mistakes from the Bensen era that have injured or killed our friends. It's not because anyone dislikes you, quite the opposite. We want you around to share your excitement over flying, and maybe even post some flying pictures in years to come!

[GyroRon]

Two things come to mind,Herb Cox and Bill Parsons, Both killed by control system failuer
These two men had many ,many hours in the air in gyros. except for rotor blade or control rod failure most every thing else will call for unplanned landing.Except if a engine should deciede to leave its mount. Ron is right all my bitching to him was not in vain.As Ron said,Just my two cents worth!
Bud O'Neal


Bud, I can never thank you and the rest of the sunstate rotorclub enough for the education you guys gave me!

It might be hard to believe, but I was probably more stubborn on things probably anyone else. Thanks to Bud and Catfish and many, many others in Sunstate I did the right thing!

Bud, don't EVER hesitate to give me a good bitching! I got wide open ears :D

[Ron Marlett]

Paul
That was very well put. Past records for gyros are not great, even recent history does not leave the gyro in a very favorable light. If you go play airport bum at your local FBO(especially a field that dosn't have any gyros operating there) and bring up the subject of gyrocopters, you will probably be met with something like "Gyrocopter, you won't get me in one of those death traps". Kind of ironic when you consider Cievra developed the gyrocopter to improve flight saftey.

I recall a man here in Port Angeles nearly 20 years ago when I was starting out my fixed wing flight instruction. He purchased a complete Mac powered Benson and a towed Gyroglider. He was self teaching and did many runs in the towed glider before attempting a unsuccessfull first run in the powered gyro. I didn't witness the crash, but it was said that he porpoised a few times shortly after lifting off and struck the runway hard. As I recall the prop blade severed the front half of one of his feet. I don't recall if this gentleman had any pilot ratings, but this was just another story to confirm the generally held truth that gyros are dangerous and that anyone wishing to fly and live should avoid them. Even our successfull emergencies sometimes dont help, irregadless that the engine failure that caused the unscheduled landing resulted in the gyro landing in a small pasture or soft plowed field and the pilot walking away where a fixed wing plane in the same circumstance would have been destroyed and the pilot probably injured. The only thing that seems to get remembered is that another Gyro came out of the sky.

Don
Brian Jackson brings up a good point about prop thrust line in relation to the center of gravity(CG). The Gyrobee maintains its thrustline within a few inches of the CG mainly because the reduction gearbox on the Rotax engine is oriented down below the engine. This raises the second largest mass on the gyro(after the pilot) above the thrust line making the overall CG when the pilot is in the seat between 1-2" below the thrust line. I noticed that your belt reduction places the prop thrust above the engine. I also noticed the battery(another heavy object) is setting down on the keel. You have moved the weight of the fuel up a bit with the seat type fuel tank but the seat tank's CG is still lower than the thrust line. Granted, I have not yet started the construction of my own Gyrobee, but for many years I have been following the successfull progress of others through this forum and previously on Norms forum. I have also followed the failures of others via the NTSB reports and these forums. I also can do weight and moment calculations. But even without doing any math as pictured, with all the CG's of all the major components of your craft, including a seated pilot, located below the prop thrust line I would estimate the overall CG of your craft to be significantly lower than the propeller thrust line. A high thrustline is probably what helped to kill that 20,000 hour pilot that Paul mentioned even after enough dual instruction in a gyro for him to obtain a solo sign-off.

Is it possible to re-orient the belt reduction unit on your engine below the engine and raise the engine up higher on the mast to keep the propeller at the same height? I know this means some new mount structures but it would go a long ways to raising the overall CG.

As for dual instruction, I think that can be had as near to you as Seattle/Auburn WA. How much is your continued good health worth to you? In conjunction with Gyroron's offer, It is surely worth more than 10 hours of round trip driving.

Your Success is our success, But your failure is also our failure.

Good Luck

Ron

[Vance]

It might be hard to believe, but I was probably more stubborn on things probably anyone else. :D
Hello Ron, I don't find it hard to believe. One of the things I admire most about you is that, after a bitter struggle for your point of view, you will yield and embrace an oposing view. I think your offer is paticularly generous and I am pleased you broke through with Donald. Thank you, Vance

[Brian Jackson]

I mirror Vance's comment. Ron, That's an amazingly generous offer to Donald. Whether you know it or not now, you sir have just become a hero to Donald's family at some point, and they may never know it. Things you do earlier in someone's future affect everything subsequent.

Smiling and happy,
Brian Jackson

[BUD ONEAL]

You do good Ron, Keep it up.
Bud

[bogman]

I myself will personally pay for one hour of dual instruction for you if you will go get it - just email me after you have gone to the instructor and I will send you a check priority mail. Just please send me a reciept

That is a good thing. Put me down for one hour too.

[GyroRon]

Please guys, don't make my head swell. I am just doing what has been done for me in years past.

Still surprised no one has asked about my code at the bottom of my sig.... :)

[banaari]

Still surprised no one has asked about my code at the bottom of my sig.... :)

OK, I'll bite. :D
What's with the code at the bottom of your sig?

Cancel that thought. I've just seen what it is.
Do NOT tell me. :p

John

[Silverwing]

Sic........ :)

[Brian Jackson]

Please guys, don't make my head swell. I am just doing what has been done for me in years past.

Still surprised no one has asked about my code at the bottom of my sig.... :)
Well there ya go! And regarding your sig message, 370HSSV M0773J >|CVE] 0773H

[banaari]

773M SV 9NI773MS V 3AVH I '3W d73H

[Brian Jackson]

John, Try A & D ointment then!

Man, did this thread mutate or what? Ron, start a new "bull****" thread so we don't hijack this one.

[skyguynca]

I saw your site some time ago when I looked at you email address. Nice looking but has it flown? I am on the same airport as the Trek Aerospace guys and I think there platform for UAV and Manned looks cool too but it doesn't really fly, it just hovers. I really would like to see one of the machines really fly, no hype just fly Mosler had alot of hype and hover footage like the rest but no flying footage. Have you guys flown yours yet?

[automan1223]

Could not have said anything better myself. Do not take any of this picking on you as cruelty. We all have been around the bad stories long enough to know that there are some things you cannot take a chance with. We as a group have burried too many of our brothers and do not want to see any more perish to hard head'd ness or stuborn stupidy. No reason to go it alone now a days.

Jonathan

[Brian Jackson]

I agree wholeheartedly. I think it's just great that, with the aid of this forum and the kind folks herein, we can share a collective "mind" (no Borg jokes!) where safety and building/flying practices are concerned. In the few short months I've been a member here asking questions and learning from the experts, I've accumulated a wealth of knowledge that may have taken years otherwise. What's more, with this knowledge comes the sobering realization that I've a long way to go to even be in the same league as guys like Chuck Beaty, Ralph Taggart, Doug Riley, etc., just to name a few. And the fact that gentlemen like Donald inevitably come to the same realization that there's much to learn here, makes me proud to be, in some small way, a contributing member. One of the things I'm still learning is knowing when to just shut up and listen to the smart guys!

Respectfully,
Brian Jackson

[LAWOLF]

I saw your site some time ago when I looked at you email address. Nice looking but has it flown? I am on the same airport as the Trek Aerospace guys and I think there platform for UAV and Manned looks cool too but it doesn't really fly, it just hovers. I really would like to see one of the machines really fly, no hype just fly Mosler had alot of hype and hover footage like the rest but no flying footage. Have you guys flown yours yet?
I have not flown it yet but the BELL X-22A flew in 1978 and was a very good aircraft but was very heavy. It weighed 15,000 lbs and had 5000 SHP to fly it and it took 2 pilots to control it but was used as a testing platform for the NAVY and ones that use the tilt rotor. Mine is very light and is computer controlled with 50 computers very small about 1.5 x1.5 x 0.5. The controls are all servos that we have today and in the Bell it was Hydrolics and moog valves very heavy. I have had the control software completly designed and have flowen it on a computer program which you put in all the numbers and it will see if it will fly you don't need a test pilot. This year we are going to build the small model to use a camera and relay for the Customs and send the info bact to HQs for evaluation. The little BEE-220 with the electric motors makes it able to carry 30 lbs but the flight time is only 1.5 hours but I am looking into solar panels that are flexable and can be glued onto the outside skin. The big one will have to wait since all the parts and motors are about 3 million. The model is 5K with all the equipment. These prices there is no labor or profit.

[skyguynca]

Very nice, keep us informed looks like fun

[Doug Riley]

Don, the thrustline (TL) location IS key. What's important is the position of the TL compared to the position of the gyro's center of gravity (CG) in the vertical axis. This is a completely separate issue from the usual CG location exercise -- the usual one has to do with the position of the CG in the fore-aft direction, while this one concerns its position in the VERTICAL direction.

If the TL is much higher than the CG, the gyro will have a strong tendency at high power settings to flip forward upside down in the air. This type of accident has happened scores of times, and is always fatal. It happens in a heartbeat. It has given gyros the awful reputation that they still have.

The thrustline ideally will pass right through the CG. If the TL is an inch or two higher than the CG, the push-over tendency can be neutralized by a horizontal stabilizer. If the TL is much higher than couple inches above the CG, then the horiz. stab probably will not be enough to make the craft safe and stable.

Your setup may have a thrustline-CG problem. Normally, when you use a large-diameter prop and a redrive that puts the center of the prop above the engine's crankshaft, you do create a high-thrustline problem. A key feature of the original Gyrobee was that it placed the Rotax reduction drive in the "down" position. This helped keep the thrustline low and the CG high. The result is that stock Gyrobees have the thrustline within an inch or two of the CG in the vertical direction. Since your redrive offsets the prop above the crank, you may have a CG offset of 4,5,6 or more inches. That amount of offset occurred on the early Air Command gyros of the mid-80's. Many, many of them pitched over in the air and killed their pilots.

There are tests to check for CG location. I hope that someone else on this forum will give you some links to discussions of the tests -- if not, I'll write them up all over again for you. The procedure is basically an expanded hang test.

If you have a thrustline problem, there are various ways to fix it. One is to move the engine up and install the redrive so it offsets downward. Another is to raise the seat (move pilot and fuel up).

It's strange that a gyro gets MORE stable as its CG gets higher -- it's just the opposite of land vehicles. We've learned the hard way that this is true, however.

[gyropilot]

John Lnndy at 360-481-5519 a CFI and can sign off on a sparrowhawk in Auburn, WA at 135/hr with 20 hours of instruction.
Randy Copien above can do the same and at the same rate as John Lnndy.
So for a CFI sign off it can cost $2700 dollars.Don,

I think you may have gotten a couple of names crossed up in your discussion with Randy Coplen...

John Landry (me) is not a gyro CFI... nor an instructor of any kind for that matter! I do however fly a GyroBee in the Seattle area and would be happy to give you advice on that particular machine. I should mention that I agree with 99% of the advice you've already been given here on the forum.

Now Dave Overman is the gyro CFI who works with Randy Coplen and trains at Auburn, WA (south of Seattle) in a Sparrowhawk.

Another gyro CFI in the Pacific NW is Scott Malone of Soma Aviation. He's based out of Hillsboro, OR. Scott currently trains in an RAF-2000 gyroplane by appointment. He's usually willing to travel to a student's location under the right circumstances (he's got to be able to make a living). He also has an open-frame 2 place gyro (which I trained in), but as far as I know he hasn't used in it awhile. He can be reached at (503) 661-3266.

Best regards and good luck,

John L.

[LAWOLF]

Don, the thrustline (TL) location IS key. What's important is the position of the TL compared to the position of the gyro's center of gravity (CG) in the vertical axis. This is a completely separate issue from the usual CG location exercise -- the usual one has to do with the position of the CG in the fore-aft direction, while this one concerns its position in the VERTICAL direction.

If the TL is much higher than the CG, the gyro will have a strong tendency at high power settings to flip forward upside down in the air. This type of accident has happened scores of times, and is always fatal. It happens in a heartbeat. It has given gyros the awful reputation that they still have.

The thrustline ideally will pass right through the CG. If the TL is an inch or two higher than the CG, the push-over tendency can be neutralized by a horizontal stabilizer. If the TL is much higher than couple inches above the CG, then the horiz. stab probably will not be enough to make the craft safe and stable.

Your setup may have a thrustline-CG problem. Normally, when you use a large-diameter prop and a redrive that puts the center of the prop above the engine's crankshaft, you do create a high-thrustline problem. A key feature of the original Gyrobee was that it placed the Rotax reduction drive in the "down" position. This helped keep the thrustline low and the CG high. The result is that stock Gyrobees have the thrustline within an inch or two of the CG in the vertical direction. Since your redrive offsets the prop above the crank, you may have a CG offset of 4,5,6 or more inches. That amount of offset occurred on the early Air Command gyros of the mid-80's. Many, many of them pitched over in the air and killed their pilots.

There are tests to check for CG location. I hope that someone else on this forum will give you some links to discussions of the tests -- if not, I'll write them up all over again for you. The procedure is basically an expanded hang test.

If you have a thrustline problem, there are various ways to fix it. One is to move the engine up and install the redrive so it offsets downward. Another is to raise the seat (move pilot and fuel up).

It's strange that a gyro gets MORE stable as its CG gets higher -- it's just the opposite of land vehicles. We've learned the hard way that this is true, however.
Is there a detail drawing on how to make the measurments of the CG and the thrust line?? If so please lit me know the details on what to do in a hang test which when I did this the gyros nose went down and the upper stick had a 8.5 degree lean with 180 lbs on it with 2 gallons of gas and 4 quarts of oil in the engine. I can measure all the positions you want and give it back to you for a look and then you can figure out where the positions are for safe flight.

[LAWOLF]

Is there a detail drawing on how to make the measurments of the CG and the thrust line?? If so please lit me know the details on what to do in a hang test which when I did this the gyros nose went down and the upper stick had a 8.5 degree lean with 180 lbs on it with 2 gallons of gas and 4 quarts of oil in the engine. I can measure all the positions you want and give it back to you for a look and then you can figure out where the positions are for safe flight.
On the upper stick from the TL which is 34 inches from the top of the lower main tube. The weight at their locations going up the stick from the TL to the actual rotor blade comes out at 2432. The weight going down the tube from the TL comes out at 2435. This is with fuel and everything except me at 180 lbs. The weight below the TL less fuel is 1454. So if I am sitting in the seat the weight below the TL will be much higher. So what do you think??

[Doug Riley]

Don, sounds like you've got the idea. It's the same method as doing a weight-and-balance on an airplane, but vertically around the prop thrustline (as datum point) instead of horizontally.

Yes, the pilot's weight will bring your CG well below the thrustline. That's what usually happens with Bensen-style seating unless you use a very short prop (like 48") as Bensen did. Your 68-inch prop forces you to move the prop upward compared to Bensen, which gets the prop thrustline and CG out of alignment. The original Gyrobee minimizes this problem by using a reduction drive that offsets the prop BELOW the engine (the engine is above the prop).

The CG of a typical seated person is right around his belly button. Sit in your gyro, measure the distance up from your navel to the prop thrustline, multiply the distance by your weight and you'll have the numbers you need to ESTIMATE your CG location. Same method as adding luggage to a FW plane. I would GUESS that once you add your weight (plus fuel) in the seat, you'll find that the CG is 5-6 inches below the prop thrustline. That's enough to be a worry.

It's still a good idea to verify the numbers on paper by doing an actual double hang test, however. This involves hanging your gyro from two different points on the frame and taking photos of both "hangs." I'll write up the full procedure and post it (for the Nth time!!) in the next day or two if nobody else does. John Landry has better pictures of this than I do, though (John, you out there?).

[Brian Jackson]

Doug,
Ask ToddP to create a "Sticky Thread" of the double hang test essay. I know he's looking for info like this that gets requested often so people don't have to post it a dozen times for everyone whom asks. That's what the Sticky Threads are for.

Just a thought.

Cheers,
Brian

[chuter]

Here's a link to a thread where I posted pics of my double hangtest:
http://www.rotaryforum.com/forum/showthread.php?t=3923

My calculated CG location and the location determined by the pics were quite different. At this point I'm inclined to believe the pics more than the calculation because I was using some pretty cheap, not-alway-accurate scales.

I used a CG calculation program from Ralph Taggart's website, and the spreadsheet that C. Beaty had posted on the old forum.

[Cobra]

Chuter,
Id like to thank you for the last link regarding hangtest- to me it illustrates very well the effect that the pilot's weight has on the location of the CG (particularly in the second photo). Like they say, a picture is worth a thousand words.

[PW_Plack]

For that matter, even if you know the pilot's weight, you still need to hang. The pilot's own center of gravity can vary widely based on genetics, lifestyle and age!

[Doug Riley]

I've attached a draft of an article I will send into the PRA magazine on this topic. The pictures aren't there yet, but Chuter's are better than mine, anyway.

Please let me know if any part of this isn't clear.

[LAWOLF]

Another thing I noticed, besides the notes on the attached image, was that the rudder "rod" only exists on one side of the airframe, meaning that it's meant to act as a push-pull rod. For the forces required, I don't see how this rather thin, unsheathed rod will keep from bending under compression loads.

EDITED: Oops, I just noticed it was a sheathed push-pull cable. My mistake.
I have the inserts in the push rods inserted into the tube 1 inch and then they are pined. I also welded the insert on the outside to seal the opening. I am changing the bolts you indicated with AN-27A type. Also I drilled through between those bolts center and inserted a 1/4-28 all the way through and nylon locked it on the other side. The flexing you spoke about on the landing wheel rods is the design by the builder of the Gyrobee. The landing wheels struts are movable and have shocks attached at the main upright. This is another design by Gyrobee.

[LAWOLF]

I've attached a draft of an article I will send into the PRA magazine on this topic. The pictures aren't there yet, but Chuter's are better than mine, anyway.

Please let me know if any part of this isn't clear.
Thanks Doug I down loaded it and will take a look. Don Law

[LAWOLF]

For that matter, even if you know the pilot's weight, you still need to hang. The pilot's own center of gravity can vary widely based on genetics, lifestyle and age!
I have mada a hang test and the nose dips 8.5 degrees with me in the seat and 2 gallons of gas in the tank along with the engine with 4 quarts of oil. Don Law

[Brian Jackson]

Excellent, Doug! Very well written, easy to follow, and spot-on.

One thing I did notice however, unless I missed something, was that in Chuter's photos, the blades are not attached. It appears there are some "canister-type" weights of perhaps equal weight (sand-filled perhaps?) attached to the hub bar to compensate. Is this true? If so, it might be worth noting in your essay on this subject.

In Chuter's case, would it not have been better to leave the blades on, since they can be rotated left-to-right during the second hang as not to hit the floor? On the other hand, since the blades cone upward in flight instead of drooping, I suppose this could affect the rotor disc's CG which might throw off the test results a tad.

This has really piqued my interest. Thanks for posting this!

Respectfully,
Brian Jackson

[Doug Riley]

You don't need the blades on during the hang from the teeter bolt. You do need them during the hang from the second point. Looks like Mike Guard made some dummy weights as a substitute. That's OK as long as you put them in at the right height -- roughly centered on the teeter bolt.

Don, you could bring the CG up with ballast weights at the top of the mast, but it's not a good idea for a couple reasons.

First, adding dead weight really hurts performance. A gyro rotor makes a pound of drag for every 4 pounds of weight you add.

Second, and more important, the top of the mast should not have a lot of mass. The mast has to be free to flex with the vibrations from the rotor. With a large mass up there, the top of the mast will tend to stand still and the rotor blades will try to "hunt" forward and backward in their plane of rotation. This hunting action puts tremendous strain on the rotor. This means that even moving some existing part of the gyro -- say, the battery -- up to the top of the mast is not a good idea. The mast must be free to flex.

Moving the gyro's CG up safely normally involves raising the seat, reversing the reduction drive, or both.

[Brian Jackson]

You don't need the blades on during the hang from the teeter bolt. You do need them during the hang from the second point. Looks like Mike Guard made some dummy weights as a substitute. That's OK as long as you put them in at the right height -- roughly centered on the teeter bolt.
Cool. That explains a lot Doug. I appreciate your hard work and ever-present contributions.

Brian Jackson

[Alan Coats]

I took the pictures of Mike's hang test. He tied a couple of dumbells to a spare hub bar to simulate the weight of the blades. The weight matched the weight of the blades and was distributed evenly. The handles of the dumbells were tied to the top of the hub bar, so the weight was pretty much centered on the teeter bolt.

Alan

Alan

[Brian Jackson]

...I am changing the bolts you indicated with AN-27A type. Also I drilled through between those bolts center and inserted a 1/4-28 all the way through and nylon locked it on the other side.
Fantastic, Donald. As they say "The Devil's in the details." Small mods like this will ensure that you and your beautiful gyro have a long, happy relationship :)

The flexing you spoke about on the landing wheel rods is the design by the builder of the Gyrobee. The landing wheels struts are movable and have shocks attached at the main upright. This is another design by Gyrobee.
I know... I'm building a GyroBee at this very moment. I'm assuming what you're speaking of is the 4" bend in the main gear tubes (axle struts). This bend was introduduced into the GyroBee design to accomplish 2 things:
1. To allow sufficient ground clearance, and
2. To allow the main gear to track vertically to the ground.

Though you have indeed bent these tubes quite correctly (and nicely done it appears), they need to be connected to the keel where they were originally designed in order to fulfill their design objectives.

Do you see that hole in the aft-end of your keel tube just behind the mast? That's the location where the axle struts are meant to be attached. Right now your axle struts are mounted forward and below their optimal placement (at the fairlead block hole on the cluster plates), which is why the wheels are out-of-track. This is a simple mistake I may have made too, but an easy fix. You may have to adjust the nuts on your drag struts a bit when moving the axle strut brackets to their correct location, but that should improve your ground handling considerably without costing a dime :D

When Todd visits you again, I think you'll be very surprised the value of a fresh pair of eyes. Hey, that last sentense almost rhymed! :)

Keep up the great work, and keep us all posted.

Respectfully,
Brian Jackson

[GyroRon]

Interesting.... in Chuters double hangtest pics the CG appears to line up with... are you ready?..... His belly button! isn't that about where it usually is!!!

[gyropilot]

See this thread for photos of a GyroBee double hang test...

HTL and CLT - Why the argument? (http://www.rotaryforum.com/forum/showthread.php?p=56811#post56811)

Regards,

John L.

[LAWOLF]

Fantastic, Donald. As they say "The Devil's in the details." Small mods like this will ensure that you and your beautiful gyro have a long, happy relationship :)


I know... I'm building a GyroBee at this very moment. I'm assuming what you're speaking of is the 4" bend in the main gear tubes (axle struts). This bend was introduduced into the GyroBee design to accomplish 2 things:
1. To allow sufficient ground clearance, and
2. To allow the main gear to track vertically to the ground.

Though you have indeed bent these tubes quite correctly (and nicely done it appears), they need to be connected to the keel where they were originally designed in order to fulfill their design objectives.

Do you see that hole in the aft-end of your keel tube just behind the mast? That's the location where the axle struts are meant to be attached. Right now your axle struts are mounted forward and below their optimal placement (at the fairlead block hole on the cluster plates), which is why the wheels are out-of-track. This is a simple mistake I may have made too, but an easy fix. You may have to adjust the nuts on your drag struts a bit when moving the axle strut brackets to their correct location, but that should improve your ground handling considerably without costing a dime :D

When Todd visits you again, I think you'll be very surprised the value of a fresh pair of eyes. Hey, that last sentense almost rhymed! :)

Keep up the great work, and keep us all posted.

Respectfully,
Brian Jackson
Well here is an update. I moved my belly button up to 30 inches by moving the seat up and that brings my seat which is a gas tank as well up and makes the upper stick balanced to the weight above the TL by calulations. I have also an option to add a 2 inch tube 9 inches long which I can fill with lead making it 10 pounds and attach it up at the gyro head between the plates. This will make the upper stick 500 inch pounds heaver if I need too. So when I do my double hang test I will see. By the way the actual prop center is 6 inches above the crank but it is on an angle plate which is attached to the VW block making the pushing area only 3.5 inches above the crank. So you take 3.5" X 248 LBS me + 8.2 gallons of gas = 868" lbs and now from the TL the upper stick is 2275.5 " lbs and the lower is 2256 " lbs . So the upper is calculates heaver. We will se after I take the pictures and match them up. Thanks Ron for the data.

[Jazzenjohn]

Several people have remarked about your method of modifying the control rods to clear the starter. They mentioned a standard solution to avoid obsticles. If you were unclear about what that is, there is a picture in the For Sale section "Gyro for sale at Benson Days" if you look at post #2, middle picture, you'll see what they were talking about.

[Brian Jackson]

Donald,
Sorry it took a while to get this to you. Regarding the gear tube thing, this is the correct location where the Axle Struts should attach to the keel. By relocating where they connect from where you currently have them attached, the wheel tracking should be spot-on. If memory serves, this hole is rather close to your cluster plates, perhaps too close to accommodate the brackets. If so, you can add a small, square spacer the same thickness as your cluster plates between the keel and the bracket so that they mount flush, partially overlapping the cluster plate. If there is enough room, then nevermind. :D

The existing bend in your Axle Strut tubes should provide adequate ground clearance, especially since you're not using a Fairlead Block for the rudder cable(s).

Hope this helps.

Respectfully,
Brian Jackson

EDIT: I just uploaded the existing photo and see that the hole is indeed too close to the plates. Being that this is a non-critical area, you might be able to drill a new hole further back than the existing hole without affecting anything structurally, but I'm going to let a more experienced builder chime in on this one. Guys?

[Kevin_Richey]

Don,


Another gyro CFI in the Pacific NW is Scott Malone of Soma Aviation. He's based out of Hillsboro, OR. Scott currently trains in an RAF-2000 gyroplane by appointment. He's usually willing to travel to a student's location under the right circumstances (he's got to be able to make a living). He also has an open-frame 2 place gyro (which I trained in), but as far as I know he hasn't used in it awhile. He can be reached at (503) 661-3266.

Best regards and good luck,

John L.


CAUTION TO GYRO STUDENTS OR BUILDERS!!!!!!!!!!!!!

Use extreme caution when dealing with Scott Malone either as an instructor, parts supplier, or for any type of aircraft sales.

There are more than a few who have paid plenty for one of those or any combination of them and have been left high and dry without anything to show for their hard-earned dollars.

His gyro CFI and BFI ratings are suspect and bring plenty of doubt about his ability to legally log time in your logbook for his instruction. The PRA's Rotorcraft magazine President's Column a couple of issues ago (Dec/Jan, I believe) dealt with this exact subject, stating that the PRA get calls about gyro instructors who are not on the list of legal gyro CFIs.

The gist of that column was that unless an instructor has completed the requirements of exemption 5209, which the PRA administers, they are not legal to instruct as a gyro CFI.

Check with the PRA and ASC to see if he has a gyro instructor rating (the PRA's is exemption 5209 from the FAA) and find out for yourself. I cannot say anything about his heli CFI rating.

He may have had these ratings at one time (but I have never seen his name as a gyro CFI on the list published in ROTORCRAFT magazine). I checked with the ASC (Aero Sport Connection) once and they did not have him current when he was actively instructing as an AFI (Advanced Flight Instructor, one who can recommend students to become BFIs)

He has given instruction and not signed a student's log book for the hours paid for, even after repeated attempts to get him to do so. I personally know one of these victims locally who paid for training to get a BFI rating and couldn't get Mr. Malone to give him the necessary sign offs for him to become a BFI, after completing the training and paying the necessay licensing fees.

He also has burned many folks who have paid for gyros, gyro parts and never delivers anything but lots of excuses and stalling maneuvers. Returning of repeated phone messages left for him on his business phone is almost non-existant.

The complete puzzlement about all this is he is a nice guy and reportedly excellent instructor!!!!!

My two cents and that of many others with whom I have spoken with about his shoddy and dis-honest business practices.

If you feel like throwing away your money, then spend it with him!!!!!!!!!!!!!

[Chuck Roberg]

Kevin, I'm not disputing any of you post. I just would like to clarify one point.

A Gyroplane/CFI only needs the 5209 exemption to instruct in an experimental gyroplane in which he charges for. If a student has his own 2-place gyro and wants to hire a Gyroplane/CFI the student is free to do so. The instructor does not need the 5209 exemption in this case.

Just found this on the FAA site;

SCOTT MATTHEW MALONE
Address

Street 734 SW HALSEY ST

City TROUTDALE State OREGON
County MULTNOMAH Zip Code 97060-1371
Country UNITED STATES




--------------------------------------------------------------------------------



Medical


Medical Class : Second Medical Date: 05/2004




--------------------------------------------------------------------------------



Certificates

2 of 2


1 2



DOI : 04/23/2004
Certificate: FLIGHT INSTRUCTOR

Rating(s):

FLIGHT INSTRUCTOR
AIRPLANE SINGLE ENGINE
ROTORCRAFT HELICOPTER AND GYROPLANE

Limits


VALID ONLY WHEN ACCOMPANIED BY PILOT CERTIFICATE NO. EXPIRES: 30 Apr 2006.

[LAWOLF]

Several people have remarked about your method of modifying the control rods to clear the starter. They mentioned a standard solution to avoid obsticles. If you were unclear about what that is, there is a picture in the For Sale section "Gyro for sale at Benson Days" if you look at post #2, middle picture, you'll see what they were talking about.

You must use 100 mile duct tape to keep out all the rinkles. I have modified the upper control rod by 30 60 90 plate on both sides of the 90 degree areas. What is hard to see is the joint on the outside is a solid piece of steel of which the rod joining the two areas is sleeved through the steel joints and welded at the top and there is a hole on the outer side towards the seat which is welded to make the tube not come out of the steel joint. Then the section joining the two rods top and bottom is pined and welded. So now it has 4 inch welded plates both sides of the joints which connect the main rods to the other joining rod. I do not think it will brake.

[Brian Jackson]

I sure does but I have a question what is the hole on the area of the bracket for that I have attached? Second if you look at the prints the hole you have used for the correct location of attachment states .75 inches from the end of the square tube. I have looked at the rod position going up to the SS plate for the wheel strut to allow the wheels to have a bunge cord attached to make a shock device. The plate is attached to the upper tube and is SS and 1/8 inch thick. To find the middle of the plate you have .0625 and then over this plate is a clevis which has a bolt through to allow the axle to move up and down. That puts the center of the rod going down to the wheel at .0625 for the alignment to be perpendicular to the frame. The drawings indicate .75 from the end for the hole to attach the axcle bracket which makes the axcle back from the CL of the upper plate by 1.1875 to the rear of the Gyro making the action of the upper axcle stick out of alignment when it rides up and down on the upper plate. I know you can make the axcle 90 degrees from the main tube by the adjustment of the front rod but I am not sure of the other I am going to make the upper rod more true by allining the rod and placing the attachment almost very close to the outside of the plate which holds the upper stick. If you know please let me know.
Donald,
Thanks for the inquiry. You are correct that there is indeed a slight offset, if I read your post correctly (see first image - side view). The main gear is actually set back behind the mast slightly, and per your observations, the diagonal strut runs up to the Shock Plate (image #2) at a slightly skewed angle when viewed from the side. Because the slots in the shock plate (image 2) are angled inward, the gear loading does not impose undue stresses on it when deflected. It somewhat follows the "arc" shape of the gear movement.

I can see where it would seem to make sense to have the gear deflect vertically, but I trust Mr. Taggart (the GyroBee Designer) located the gear a bit aft for good reason. Not being privy to the more esoteric design criteria, I can only convey that the stock design works, and quite well.

If I've missed anything please let me know. Sorry about all the CAD images, (especially if you're on a dial-up connection :eek:) but it helps me communicate geometry that might otherwise be difficult to explain.

Thanks,
Brian Jackson

[GyroRon]

Stock gyrobee gear installed per plans apparently eats up the bushings used in the slide on the mast. There is supposed to be a mod or tweak to fix this I have heard discussed by other gyrobee builders.

[Brian Jackson]

Stock gyrobee gear installed per plans apparently eats up the bushings used in the slide on the mast. There is supposed to be a mod or tweak to fix this I have heard discussed by other gyrobee builders.
I've heard this too, though I'm unaware of the mod. Could you point me in the right direction?

Thanks Ron.

Brian

[RICK MARTIN]

Yes I have already had this problem with the little pieces of aluminum tube which serve as bushings. It could be that some of us are not being careful to make the inside of the SS slots REALLY smooth. Any way, I made a set out of stainless tubing and keep extras in my tool box. Ralph acknowledges this is a weak point and that it shoud be checked at least once each season. You definitely don't want that bolt to break.

[PW_Plack]

Don,

On the idea to add ballast to correct vertical CG, don't miss the point made earlier about avoiding adding mass to the top of the mast.

I admire your openness to the experience of others. The whole tone of this thread is now back to something in keeping with the term. "Welcome Mat." :)

[Dean_Dolph]

I would just like to say that Don joined us and the reaction to his initial presentation must have seemed more than a little hostile. It isn't the reception that new members normally receive but then again Don's presentation triggered the concern of all which doesn't normally happen in the Welcome forum.

Don's initial response to the welcome was natural, I believe, but he has shown that he has the resilence to adapt and provide an open mind. He has my respect for that. However, the resulting discussion contains some interesting and important info and should be in another forum, such as the Gyrobee one. I'm not sure everyone checks in to the Welcome forum.

[GyroRon]

He said he was ready to fly the gyro as it sat and with no training. Saying that we had two choices.... Sit back and watch and see if he hurts himself - and the image of our sport - or get straight to the point and use any means needed to get him to stop and rethink and after some training and some tweaking, Then go flying. It worked as far as I can tell.

Had he came here and asked what we thought or said he won't fly it till it passes the approval of at least the majority and he was going to get lessons first, then the approach we used would have been the wrong one!

[barnstorm2]

http://www.pra.org/

Scroll down and there is the basic Benson Days info. It starts this week and goes through the weekend. I don't know what the admission price is I think it was like $10 last year but I don't recall.

[Doug Riley]

Don: If you can't make Bensen Days (since it's happening right now), you migh consider the next national gyro event: the PRA Convention in Mentone, Indiana. It's just before Oshkosh and not too far away, so you might be able to take in both of them.

Finally, there's Rotors Over Carolina (in S. Carolina) on Columbus Day Weekend in October. Being in the Southeast, it draws many of the same crowd as Bensen Days.

There are other large regional events, including some at El Mirage, California, a gyro hotbed for decades.

[LAWOLF]

Well this Friday Tod and myself will possibly get together to setup a time to make the double hang test that everyone has suggested to see if the thrust line TC on the propeller is on the CG line on the upper stick. I have moved the seat up and made other adjustments to do some of the suggestions made on the forum. Now it is up to the test and Tods suggestions. I hope to fly this Gyro this year when it stops raining and gets a little hot and stops being only 34 at night and 48 during the day. Gets cold up there as you climb into the sky.

[LAWOLF]

Well I took the LAWOLF out for a run at the airport and found that I needed brakes on the rear wheels to stop this fast machine. I contacted Ken Brock down in LA and they did not suggest using the hydrolic brakes they had designed since they tended to lock up the wheels. So I went to the internet for a look and found nothing that looked like they would work. So I went to the local motorcycle shop and bought one set of brake shoes and came home to design my own brakes. I have designed the brakes now and have installed the shoes along with the cables and springs to stop the wheels by just using your heel next to the rudder peddles. The brakes are independent of each other and will help in the turning of the Gyro when you are going slow and do not have enough speed or thrust off of the engine prop. I will see this next week how they work and will report back. The cost of the brakes was 15 dollars plus four rollers to feed the cables at a cost of 10 dollars and cable of another 5 dollars making a total of 30 dollars. We will see how effective they work. They fit inside of the wheel rim and work against the inside rim to do the job of stopping and since you don't use them very hard for control will not wear the rim much I believe at this time.

[LAWOLF]

For the CADD people this is the physical way to section an aircraft see attached picture.

[Brian Jackson]

For the CADD people this is the physical way to section an aircraft see attached picture.
Wow, I didn't know Ginsu even made props!