"Helicopter Aerodynamics" - remarks & questions
Hi, I am a private pilot, working towards my commercial, new to this forum, and I have a couple of remarks and questions regarding helicopter aerodynamics in general, and more particularly about "helicopter aerodynamics", Ray Proutty's wonderful book.
I will start with the remarks:
- I had a hard time finding this book. It has been out of print for a while (mid 80s I guess!) so I bought it used. I wish it was re-edited so more pilots could have access to it.
- I believe it is essential reading if you want to understand helicopter aerodynamics. I read Leishman's "principle of aerodynamics" and Stpniesky's "rotary wing aerodynamics" but I wish I had read's Proutty's book before. By simplifying everything and making it so clear, I believe he actually gives the reader the best foundation to then read the more advanced texts (as opposed to a more general but technical aerodynamics book like Anderson's "Intro to flight").
- On this forum and a few others, there are always these questions about dissimetry of lift, flapping, etc... Then usually, some experienced test pilots dispel all doubts about how things work. Well, I think in most cases first reading Proutty's little book would answer all these questions.
Now my questions:
- Has anybody read the sequels "More helicopter aerodynamics" and "even more helicopter aerodynamics"? I heard a rumor that they did not add much to the first book (maybe a lot of the stuff was recycled). Can anybody confirm that? Should I try an get these books too?
- In the fourth chapter of "helicopter aerodynamics", Proutty introduces flapping/dissimetry of lift. He refers to de la Cierva's first autogyro which had a rigid rotor and "rolled over and thrashed its blades into toolpicks" on first takeoff. However, to me, if that gyro rolled over it is not directly due to dissimetry of lift. On a rigid rotor, dissimetry of lift in forward motion will create a pitchup moment as the blades flap (but since it is a rigid rotor the whole rotor is tilted). So maybe some transverse flow effect created a rolling movement, but I do not see this crash as a direct illustration of dissimetry of lift.
And a final side note, about what appears to me as an unfair situation:
at the NTPS (National test Pilot School), they offer all kinds of interesting courses for test pilots and flight engineers. In my opinion, some of this stuff could be beneficial to all pilots, not just test pilots. The fixed-wing people at NTPS seem to agree with that, since they offer a series of courses about spins, inverted flight and so on for all pilots. On the helicopter side, however, there is no such training offered. Would it not make sense for the NTPS to offer courses on unusual attitudes in helos? Show how helos behave at the limits of their flight envelopes?