Turn dynamics

wrote in message
oups.com...
[...] Does it seem counterintuitive to
push on the yoke to maintain altitude in a turn? Something sounds
fishy.

Sure, of course something sounds fishy. That would be your clue that your
analysis is wrong.

I don't fully even understand what you're trying to propose. For one, you
can't increase your load factor (and thus lift) without either increasing
thrust or decreasing airspeed. The moment you increase the lift, drag
increases and the airplane will start to slow down until thrust equals drag
again.

As far as the parts of your question that I think I comprehend go...

From personal experience, at 100 knots in a C172, you will remain on the
"front side of the power curve" with the proposed maneuver. That is, a
reduction in airspeed will compensate for the increased drag. That said, of
course if you select a power setting that provides less thrust than the
minimum drag at the doubled lift, you cannot expect to enter a 60 degree
bank and remain in level flight. Even at L/Dmax, engine thrust will be less
than drag and the airplane will slow further into the "back side of the
power curve". Only by descending can you get enough thrust to balance drag.

Note that in this latter case, being on the "back side of the power curve"
won't help you. Yes, speeding up would reduce drag, but the reason you get
into that situation in the first place is that there's NO airspeed at which
you can reduce drag enough to be below or equal to the available thrust.
Even if you speed up to exactly L/Dmax airspeed, you still need to maintain
a descent, because there's just not enough engine thrust. All that speeding
up gets you is a shallower descent angle (just as would be the case in a
straight-ahead descent).

In other words, being in a 60 degree bank doesn't change the basic
concepts...only the specific airspeeds at which things happen. This all
assumes, of course, that you *start* on the "front side of the power curve".
If you are in level flight on the "back side", then yes...speeding up allows
you to fly with less thrust, the excess then which you can then use to
compensate for drag induced by a bank.

All of the above is posted in good faith. You are correct when you say you
were confused back when you posted previously, but I have to say that
today's post exhibits some of the same "overcomplicating" behavior we saw
back then. You don't get something for nothing, and no matter how you
manage to state the question, the airplane always flies the same. I hope
this question doesn't devolve into a similar quagmire as we saw "back then".
I know I don't have the patience for it.

Pete