PPO training

[asra]

quote from stability idea topic:A pilot with hundreds of ours flying on the coast (vegi flying) is no match for a 30hr pilot flying inland dealing with thermals.If we were taught on an unstable machine and survived then we should be right.the best improvement we can make to design is our KNOWLEDGE and awareness of the particular craft we fly and behave accordingly./quoteI have around 30hrs flying in thermally conditions with a thrust line about where my head is. Did basic training on a factory ship.

[bones]

I have around 30hrs flying in thermally conditions with a thrust line about where my head is. Did basic training on a factory ship.

[Dewie]

.
..........

[asra]

PPO, is Power Push Over, which follows with a bunt. A bunt is usually unsurvivable. Did you mean PIO Pilot Induced Oscillation (porpoising) Reason is this is normally experience by the new pilot in an unstable machine. And as you say, it is controlable if you are able to feel and see it happening. Once it starts it can be overcome and rectified safley. My biggest issue is, if you understand what is actually happening with relation to your machines, Thrust Line, offset, Rotor Thrust Vector, and CofG, given you hit a big enough sink, with a high power setting and large enough thrust line offset, then the machine could bunt within a second. This may be even to fast for the best of pilots.Why build an unstable machine, when you can build one of the most stable machines which would make even fixed wing pilots envy.

[Disco]

That was good to read sam.

[asra]

Hi DiscoAs an example, imagine air moving vertically hitting the blades at say 90 degrees (from above or below) to there axis of rotation. If you remember vectors, then consider this.Blades moving say at 400 knots,

[Brian]

This post raises an interesting issue, why interesting?? well, at this moment there is no particular requirement for an instructor to instruct in any particular gyro [HTL/ CLT etc etc] and so the students responses to certain situations could well be in line to how stable a particular gyro is. I think an ELA was mentioned, well, after flying one briefly, I think anyone getting themselves into bother here in "normal " flying would be reasonably remote.Another point is that we have a pilot, [Bados] who at 30 hours has already had a quote" crash", how this occurred hasn"t been mentioned but from what Bados has posted [and not trying to be smart or anything else ] shows that they haven"t a good grip on a subject that they should have covered in instruction. Am I wrong ??? Also, I agree that a pilot with hundreds of hours should be in front of a 30 hour pilot BUT I would like to think that a low hour pilot would SLOWLY work their way into tougher conditions such as thermals and rough flying conditions no matter what type of gyro they are flying as the possibility of getting into really serious trouble with fatal consequences is very real.In my case, I had approx 1500 hours FW experience in outback conditions before learning to fly gyros. Once Rosco was satisfied, I graduated onto my own gyro [htl] and started right from the very first exercise up to balancing on the mains /hops and then circuits BUT only in calm air. Once I had the above under control, I started flying around and gaining experience [all in calm air] and I would have had at least 50 hours up before I started flying in rougher conditions but all the time working my way into tougher conditions and this is the way I personally would like to see every new pilot start off.Having gotten a few hours up in all types of conditions flying a HTL gyro, thermals /whirly whirly"s hold no dangers to a gyro, the pilot is the weak link, the hardest thing to do in a seemingly vertical climb with a missile under your gyro is to sit still, reduce power and enjoy the ride cause until you get used to it, thats the best and safest course of action. How far will you go up ?? Well, most times you will hit the top after a 300/ 600 feet, it could be a gentle top or it could be that you are going to go down like an elevator in free fall. Once again, sit still, hold a little back stick so that you can feel a little resistance, getting closer to the ground 100 /200 ft, apply power and a little more back stick, you should be starting to slow the descent although I have had some that is akin to hitting a brick wall where the head seems to get driven into the shoulders and it can be a bit unsettling the first 100 times

[asra]

Thanks for your replies, specially yours Brian - good to know how others believe you should ease into gyro flying.Is a PPO when the rotor provides too little drag to stop the fan from rotating the gyro around it"s center of mass? This is said to cause an unrecoverable "bunt over" if the airflow gets on top of the rotors. I"m still looking for info on these things in the BAK book so I have gone by what"s written in web forums.I take back what I said about PPO being a piece of cake. I should have said recovering from incipient PPO has blown away my misunderstanding of the topic and improved my knowledge of the machine.I just wasn"t satisfied with vague advice from non-instructors to always keep positive g loading and maintain back stick pressure and cut power when hitting bad vertical drafts to avoid PPO"ing. This advice probably saved me a few times, but I wanted to know how much power I can safely apply in low g"s and at low AS, specially when under 300" like when I had that heavy landing.To learn where power starts to rotate the machine I repeatedly got into into low g and with increasing forward stick and power. This isn"t original, blokes on the septic forum talk about doing it.Eventually there was uncommanded nose drop. I guessed this was caused by thrust beating the partly unloaded rotor.A bit of back stick brought the nose to where it should be. Cutting power did the same. Feels safer flying now, apart from the idea of bunting over within a second Sam

[asra]

PPO when the rotor provides too little drag to stop the fan from rotating the gyro around it"s center of mass? This is said to cause an unrecoverable "bunt over" if the airflow gets on top of the rotors. Just a couple of thing bados.Yes brian is right and all new un-tride manuvers, even if in a different machine should be slowly tryed and eased into.Second, you explain a bunt above as " rotor provides too little drag to stop the fan from rotating the gyro around it"s center of mass" This is not quite right, and needs to be cleared up.A HTL machine (without a correctly loaded HS) will typically fly nose down. Yes this is due to the thrustline rotating the gyro around it"s center of mass (CofG). In doing so, the RTV (rotor thrust vector, which is providing lift) moves infront of the machines CofG. This inturn holds the machines nose up against its HTL. Incalm air, it will feel as good and easy to fly as any other machine CLT, and LTL. The problem occurrs during a downdraft, were the RTV which was holding the machines nose up is suddenly reduce, causing the sudden rotation. In its simplest form this can leed to PIO, worst case cenario, can leed to PPO. In an updraft, a HTL machines RTV is still infront of the CofG. The sudden uplift will add further lift to the rotors causing the nose to pitch up. This is normally counterd by forward stick which in the hands of a low hour pilot, can again leed to PIO.A properally set up CLT machine will not pitch nose up or down in thermally conditions, due to the RTV lifting through the machines CofG.SamL....

[birdy]

G load, whether positive OR negative, has basicaly the same effect on RRPM.IOW, neg G, or "air over the rotor" dont mean they will slow down faster, coz they still autorotate in this condition.The fastest rate a rotor will slow is in 0 G.The glitch is, wen our blades are autorotateing while in a neg G situation, the RTV, while holding the same angle, is in the oppoisit direction. [ flyn down] So the RTV is actualy pushn the nose down, worsening and accelerating the situation.fortunately, for most of us, its extreamly rare.If your in a sustained neg G, the stick must be hard forward to push the machine"s ass down.The trick is be"n able to instantly know if your in 0 or neg G, and know which action suits.If in dout, stay out. [ of the ruff stuff]

[tonydenton]

sam, once again yours and others posts as very helpfull. i come out of sinks as you have described, but in the BAK it was always stated , power before attitude.clearly here it would be alter attitude before power.

[Brian]

Flying around and thinking of this topic, the thought of being able to "feel" comes to mind. "FEEL" is being able to feel through your backside/controlls etc etc whats actually happening with your gyro and whats going to happen next. The reason its so important in my mind is that the correct interpreation of that "feel" will determine what manouver"s you can do safely whether its thermals /wirlys or just generally flying or flying at low level [200 ft or under AGL]"Feel" is something you will not have straight away but its important to get enough hours up to where you do start to pick it up. This will also help with rotor management etc.Anyone who is starting off and hasnt seen Birdy & Jacko"s demo at Lameroo needs to get the DVD and see a couple of the best at work in two very difernt gyros.

[Tim]

G"day Bados,Heed well the posts from Sam, Brian and Birdy above.At 30 hours you are just at the very beginning your gyro flying education. You certainly would not be qualified to test or evaluate the boundries of PPO. We all thought that we had a pretty good grip on Gyroplane flight at 30 hours but as you gain more experience you will realise how pityfull short you were.Testing the boundries of PPO is like slowly closing a pocket knife and determining the exact position that it snaps closed before it happens. There are ways that it can be done but I wouldn"t recommend it to a beginner.

[bosca]

I don"t understand.Why do you want to test the boundaries of PPO??Like testing for a flat spin in a Victa or verging on a stall on late final using the rudder.

[Brian]

I don"t understand.Why do you want to test the boundaries of PPO??Like testing for a flat spin in a Victa or verging on a stall on late final using the rudder.