[NSRCA-discussion] Snap Rolls

[Bill Glaze]

I'm sure that most, of not all, of you folks think this subject has been beaten to death, and it has--almost.  But--
After reading Jerry Budd's posting, and the endorsement by Ron van Putte, I've been considering Jerry's postulate about our airplanes not actually stalling the wing, for the factors he mentioned.  While it almost seems like heresy, both of these aforementioned well-known R/C competitors are quite qualified to speak within the boundaries of this subject.
Now, having taped many hours at the Nats, I have been mulling over the subject of Jerry's posting, and I decided to put my resultant DVD's on my TV, and just take a close look at these snap-rolls, which I did.  The TV is a large-screen (60") diagonal HD set, and when I replayed these maneuvers, I got a surprising result.  Appearances close-up indicated visually to me that Jerry seemed to be spot-on correct, probably for just the reasons mentioned by him; the airplanes seemed to be not even close to a stalled condition.  Realize that I had a huge advantage over the judges; I was using from 20x to 30x (variable) magnification, and viewing on the large screen with a very sharp picture was a further advantage. I also had time to play and replay them at different speeds, which I did ad nauseum. 
I was also impressed with how good the snaps looked when filming; I could hear myself on the sound track saying things like "impressive", "beautifully precise" and other superlatives, while I was filming, and before  I had a chance to inspect them with slow-motion.  Understand:  they still  looked good on the screen, but:
I found upon close inspection in slow motion many examples of no discernable break, one example of a competitor using just a small amount of up elevator before beginning rotation, then instantly relaxing it.  Many seemingly used no elevator at all, but used rudder, sometimes in the roll direction, and at least one in the opposite direction of the roll.  One showed a very small amount of yaw at the end of the snap, possiblly indicating a slight over-use of rudder; still no sign of elevator.  There was little or no noticeable "coning" as heretofore being a qualifing factor in a snap. The rotation simply didn't show coning, in nearly all cases.  There were many different techniques used, and some used seemingly different inputs in snaps for 45 deg. climbs, descending lines, and level attitudes.  Few of those I filmed seemed to use any elevator at all.  As a qualifier, all these contestants were Master's and F.A.I., and, having a pretty good idea of who the high-risers were, I generally filmed those who I felt would have a larger impact at the podium at the end of the day.  Not all the actors were the bright stars, though; I had a good cross-section.
Having spent hours in this analysis, (just ask my wife) I did come to one conclusion:  even though these snaps looked beautiful, and certainly must have pleased the judges, still and all they varied from the rule book  requirements, as I understand them.
Now, I could think of a few ways to achieve the control combinations required:  ATV, Flight Conditions, excessively large control displacements, etc.  Just as I was trying to think how it was handled, I very fortunately read Brian Hebert's interview with Albert and A.C. Glenn.  Apparently, I was a giant step behind what is going on.  (I'm used to that.)  I suggest that to complement this essay, you turn to the interview in the new Model Aviation; it's an eye-opener and ties in nicely.
I'm beginning to wonder if Lance van Nostrand's and Dave Ramsey's statements concerning rules and maneuver descriptions shouldn't be re-visited.  Although judgement on that subject rightly will be resting with other people than me..
Thanks for your patience, both of you out there who aren't asleep.  In case you hadn't noticed, I'm very deeply interested in Pattern.
Bill Glaze
AMA 2221
NSRCA 2388
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