>I'm forever curious about that "on the step." Is there an
>authoritative source that documents the aerodynamics involved?
>Anybody? Three texts I have (Hoerner, Raimer, and Strojnik) don't
>cite it at all.
IMHO "On the step" is a neat way of naming the result of good efficient
flying techniques. A lot of spamcans have limited performance , especially
at altitudes around 8 or 10 thousand feet. If cruising close to the useful
ceiling of a non turbo charged Lyconental, skill becomes critical, diving
200 feet to one's chosen cruising altitude will get speed up a few knots
because of the extra power from the extra rpm. If anything happens to
reduce rpm, extra drag from control movements, turbulence, whatever, the
speed will drop and it takes ages to get back to the original cruise speed.
Bear in mind, of course the engine is at full throttle. ie 65% power or less.
In our Europa we were cruising over France at a decent altitude, (6K or so)
and going smoothly so I handed over to my less experience colleague. He was
taught to fly using lots of little control movements to keep the airplane
level, whereas I let the bird fly itself mostly and just keep it smooth and
straight, (more or less, I learnt as a glider pilot so couldn't fly
straight and level without intense concentration {{;-) ) 5 minutes after
hand over we had lost several knots, and were checking engine parameters
etc to find out what was wrong. Nothing, it was just the increased drag.
So, I still don't believe it is a myth. Regardless of what the
mathematicians say. It's surprising what can be "proven" with arithmetic.
It depends on what assumptions are made.
Graham
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