Is CLT,HS theTaliban Terrorist of gyros

You're right Stan, you have to know what you're flying. But the world we live in has isolated people from thought. How many people driving cars now, will use cruise controll on a wet road?

Phil
 
Midget,
I think you have a great idea for a mentor. Although I didn't have one persay when I started out I think I actually had several of them here on the forum.
I fly a HTL LowRider AirCommand and have for the past 4 years and I love it.
With all the constant comments about HTL and PPO on the forum, I fly with caution and respect for my machines short comings. I have thought about converting to CTL but just like the way it looks as is.
My advice to you is to take in as much info as you can from the forum, make your decision on what you want not on what others think you should get. Understand the do's and don'ts of your choice get good training and go out and enjoy the decision you made.
 
Phil, I already have one mentor; two would be even better. I have made many changes to the Air Command you flew for me last Jan; looking forward to you flying it again for your opinion on how she feels now. I think it flies great and is responding properly in pitch but I am interested in looking into a possible improvement in the HS. Look forward to seeing you again.
 
Part of the problem with these repeated discussions is that when you use aircraft type, a persons name or bring into question a pilots flying ability or decision making then it all gets emotional.

We all defend our choices and decisions, sometimes fighting our corner even when we know we are wrong in a misguided attempt to save face. I think everyone on the planet has been guilty of that at some point in their life.

Perhaps instead of talking about RAF, Dominator etc etc. we should just stick to facts.

1, It is schoolboy level science that teaches us that all things will rotate around their CofG. It makes no difference if it is a car, a gyro, or a hammer. That is simple science fact.

2, Anyone who has built a paper aeroplane or thrown a dart already knows about the restoring and stabalising effect of a tailplane.

3, Force X distance will provide a turning moment around a point. Almost any schoolboy over the age of 13 should be able to calculate this. It is basic science fact.

With points 1&3 it is easy to see that the greater the thrust line/CofG offset then the greater the force that is trying to turn your gyro away for the desired direction of flight.

Points 1&2 show that the greater the size of the tailplane or the greater the distance from the CofG (Force X distance) the greater the restoring and stabalising effect it will have.

Now that said aviation is always a compromise. We cannot have thrust aligned with CofG all the time due to different fuel quantity and pilot weights. If it is aligned exactly with CofG then maybe at full fuel we will have a nose up moment and low fuel a nose down moment, these 2 differing responses could cause problems for the pilot so perhaps it would be better to have a slightly high (or low) thrustline to ensure that the gyro responds in the same direction at any weight. It is seen from the facts above which ever way we choose to go we should keep the offset to a minimum. Not zero but as low as practical.

Same for the taiplane, we all know it has a stabalising effect so the choice is, small on a long moment arm or big on a short moment arm. We want the stabalising effects but not so much that it adversely affects control response rates. Compromise is the answer as usual.

There is of course more than one way to skin a cat and they all have compromises.

Overbalanced rotors (better explained by others) provide a stabalising effect that can help to tame larger thrustline offsets but compromises will have to be made with relatively heavier stick forces and slower response rates.

Training and experience can also provide a stabalising effect but getting to the point of having enough training and experience is the dead mans curve of gyros. A moment of inattention or slow reactions could negate all the training and experience in an instant.
 
i have read this thread for days, each day looking for something "productive" to rise from the scorched earth rhetoric. So far---nothing! Should there be an official "welcome letter" to all newbee's providing insight and encouragement and suggestions as to how to enter the sport. That would be all the ways; the poor,good, better, and best. This would not be critical of one's choices but simply lay out the options. As a near newbee, i have made my choices and do not want to be criticied for them. I continue to look for insight on what i might do to improve my ride; not insults about my ride. Is there a possibility of a mentor program; each new person provided a real person to help and encourage? Geographically difficult i realize but a knowledgeable "friend" to talk with as the newbee gets started is invaluable.

see folks this is what i was talking about, if you would go back and read my original post!!!!
 
"flying tail heavy aircraft is for suck". Other than disrespect for those who do, what is the productive input?
 
There are men here on this forum that have tried to impress on everyone the importance of using effective horizontal stabilizers and also on trying to achieve CTL. Many have listened and thankfully understood their message. I believe 100's of lives around the world have been saved through their efforts. Pretty darn impressive…..

Whether or not one decides to fly a CLT, NCLT or an HTL gyro, there is one very important part that should not be compromised….an "effective" horizontal stabilizer. That is the part that allows all gyros to fly safely; including the HTL Magni, the HS equipped RAF and AC. As long as airspeeds are high enough to keep their HS effective and the G's are kept positive, most gyros fly safely. There can come a time however, where conditions will cause a very low G force and one would then wish they were in a CTL machine….especially if the airspeed drops too low for an the HS to be effective. Keep in mind that a FW has its lifting surface rigidly attached to the fuselage…..a gyro doesn't.

Birds have been evolving for several million years since their initial design and have apparently decided that a HS is a very good thing to have…..and I'd bet that their average wing thrust is close to their CG.
 
I have question about the area of the HS. One of the major criticisms of using a large HS to offset the HTL is it becomes less effective as the airspeed decreases and that at some low airspeed could be ineffective and the machine becomes susceptible to PPO. This was one of the conclusions of Dr Houston's CAA report.

My question is if there a large HS located on long lever arm would just the drag resulting from the large flat plate (if I remember the drag force is directly proportional to the square of the velocity) area of the HS be enough to the dampen the thrust response from the engine at low airspeed and not be entirely reliant on aerodynamic forces but mainly parasitic drag forces.
 
POST #119 Says it ALL!

Just because something feels good doesn't mean it is stable. Just because someone is a talented pilot doesn't mean they can overcome physics. Geesh, why is this such a complicated concept for some of you to get?
 
Hello to Willisbr ... I think you are confused between "Retreating Blade Stall" and "Unloading the Rotor".

RBS causes a pitch up (left side stalls and is felt aft due to gyroscopic precession). Nose pitches up, rotors tend to load up again and it may repeat itself if you don't slow down and reduce pitch. I've done it in training to feel the boundaries.

Technically, unloading does stall the rotors ... but kinda all at once! It is not just one side or the other. It is the entire disk that becomes useless and it happens fast! When that happens and a high thrust line starts pushing you over (nose down) there is nothing to stop you!

Comparing RBS with Rotor Unloading is just plain wrong. On situation is recoverable ... like a car going up a steep hill with limited power, the wheels become ineffective but can stop and roll back down to recover. Whereas unloading the rotor is like a car going off a cliff. The wheels become ineffective but there is no recovery.
 
......... Is there a possibility of a Mentor program; each new person provided a real person to help and encourage? Geographically difficult I realize but a knowledgeable "friend" to talk with as the newbee gets started is invaluable.
The following is from 'Article III Purpose' in the PRA by-laws. ' ...(b) To foster, promote, and popularize education in rotorcraft among its members and the general public.' This is from the PRA Chapter 62 by-laws. '.....whose members are dedicated to the advancement of knowledge, public education and safety of privately owned non-commercial rotorcraft.'

It doesn't take much imagination to understand that the PRA and its chapters exist for the purpose of mentoring to the unknowing and in fact Chapter 62 has a formal mentoring session during meetings; informal mentoring takes place before and after meetings as well as during lunch.

This not just for newbees but for ole timers as well since none of us know all there is to know. A mentor’s lack of knowledge becomes known as soon as someone asks a question the mentor can't answer. So, the mentor benefits from these sessions also since he is expected to find the answer.

Florida has one of the more experienced and knowledgeable chapter memberships in PRA Chapter 26. So, anyone that lives there has an opportunity to be mentored if they want to take the time and put in the effort. Informal mentoring takes place at any gathering of gyro enthusiasts but it goes unrecognized as such.

The one caution I would offer new enthusiasts is that everyone wants to help and will offer what they know or think they know. But, sometimes what they are offering is an opinion; the trick is finding out if what they are offering is a fact or is it only an opinion. If you find that the majority offer the same information then it is likely that it is fact.
 
Good point for the newbies Dean.
 
Art,
I'm working my ass of right now. Remind me before the third Saturday in August and I'll come over for breakfast, ifyou guys are still doing the pancake breakfast. I'm in Lake Placid again, so it's a bit longer for me, but I can check some stuff by Yeehaw Junction on the way too and fro, and get fuel at River Ranch. I definately want to check out your machine and feel the difference in your setup.

Phil.
 
Karl Bamforth, your Post #186 is a nice summary.

I'd quibble only in one small respect: the comment that an excessively large HS results in slow or weak control response. This can be true in FW planes whose wings are rigidly attached to the frame. If the fuselage is slow to react, then the wing will be, too.

In a gyro with direct cyclic-pitch control, however, things are different. Rotations of the fuselage are not necessary in order to change the angle of attack of the rotor. The fuselage can fly at a never-changing angle, and the pilot will still have full control of the rotor. The fuselage then functions as a stable platform from which to alter the angle of the rotor to the air.

If the fuselage is quick to pitch or roll, control actually becomes more challenging. The pilot must anticipate these rotations of the frame, and take out some control input as they occur. This complication results in the famous "jabbing" control technique that Igor Bensen describes so well in his manuals and writings.

Control "jabbing" is a standard technique in the test-pilot profession for dealing with unstable aircraft --especially tail-heavy ones.

There are few maneuvers in which a frame that pitches readily may provide a sort of "power steering" or "crack-the-whip" effect. Proficent pilots can learn to use this effect to make these maneuvers more radical. In general, though, a frame that doesn't rotate readily (because it has a big H-stab) is a good thing and does not reduce control effectivess. It merely makes control more straightforward.

Incidentally, for those who talk about the H-stab losing effectiveness at slow airspeeds: please remember that propeller blast over the H-stab can result in good H-stab effectiveness right down to zero airspeed. A gyro's prop blast at full throttle has a speed of between about 80 mph and over 100 mph.
 
On the «deathtrap» label applied to the european gyroplanes with HLT, I remember clearly Birdy stating it in on one of his post, and may be M. Beaty. I would need to do a search for some others ones.
I may be rong, but i dont recall ever calln them death traps.
Hard mouthed, inefficiant, glorified bath tubs yes, but not death traps.
 
Karl Bamforth, your Post #186 is a nice summary.

I'd quibble only in one small respect: the comment that an excessively large HS results in slow or weak control response. This can be true in FW planes whose wings are rigidly attached to the frame. If the fuselage is slow to react, then the wing will be, too.

In a gyro with direct cyclic-pitch control, however, things are different. Rotations of the fuselage are not necessary in order to change the angle of attack of the rotor. The fuselage can fly at a never-changing angle, and the pilot will still have full control of the rotor. The fuselage then functions as a stable platform from which to alter the angle of the rotor to the air.

If the fuselage is quick to pitch or roll, control actually becomes more challenging. The pilot must anticipate these rotations of the frame, and take out some control input as they occur. This complication results in the famous "jabbing" control technique that Igor Bensen describes so well in his manuals and writings.

Control "jabbing" is a standard technique in the test-pilot profession for dealing with unstable aircraft --especially tail-heavy ones.

There are few maneuvers in which a frame that pitches readily may provide a sort of "power steering" or "crack-the-whip" effect. Proficent pilots can learn to use this effect to make these maneuvers more radical. In general, though, a frame that doesn't rotate readily (because it has a big H-stab) is a good thing and does not reduce control effectivess. It merely makes control more straightforward.

Incidentally, for those who talk about the H-stab losing effectiveness at slow airspeeds: please remember that propeller blast over the H-stab can result in good H-stab effectiveness right down to zero airspeed. A gyro's prop blast at full throttle has a speed of between about 80 mph and over 100 mph.

Thank you Doug, you explain things much better than I ever can.
 
Incidentally, for those who talk about the H-stab losing effectiveness at slow airspeeds: please remember that propeller blast over the H-stab can result in good H-stab effectiveness right down to zero airspeed. A gyro's prop blast at full throttle has a speed of between about 80 mph and over 100 mph.

I have an issue with this Doug, a gyro thrusting against it's own tail wouldn't display the same stability as say an arrow traveling through the air because relative airflow would be unto itself. The most you could expect would be the tail creating a counter balancing force to neutralize other forces such as propeller thrust, which of course is important because neutralizing pitch and rolling torques on the fuselage allows a gyro to survive a brief zero G event without tumbling.

If you are pumping high velocity air over a tail an angle of attack chance would be needed to effect a change in that tails lift, and at zero airspeed this would require a gyro to be tumbling, too little too late.

.
 
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