I thought the reason is it that, as you approach cruise speed for any
given trim, it takes a long time to finally get there, so I can
'demonstrate' it too. The S-Tec (autopilot) web site contains an
article debunking it. Otherwise, aerodynamics texts and NASA research
would document the phenomenon. They don't, and a credible answer as
to why not will bring me into the faith, honest. Like conspiratorial
holdover from the Cold War, 'cuz the Russians never caught on. :-)
Regards,
Fred F.
> It is real! Check out a PA28 manual the Warrior I learned in would settle at
110kts
> (if I remember right) or so at 2300rpm when throttling back from full power on
reaching
> 100kts or so, or 120kts at 2300rpm if you throttled back from full power on
> reaching
> that higher speed. I remember clearly my instructor demonstrating it to me and
my
> flight-test examiner doing the same when I throttled back early on the climb
out from
> a PFL.
> The reason is the shape of the drag curve. The drag is the same at both
> speeds,
and
> equals the thrust from the engine+prop at 2300rpm. To get the higher speed you
have to
> get the plane over the higher drag in between those speeds by using more power
or
> diving. My instructor/examiner both talked about getting onto the back of the
drag
> curve.
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