Cheers,
I had the temerity to send the below, but forgot to include the
net..... Perhaps this will explain a later email defending my secret (if
unpopular) position on the 'step'.
Happy landings
Ferg
----- Original Message -----
From: Fergkyle <ve3lvo@rac.ca>
Subject: Re: Inflight Variable Pitch Props
> Yes, Virginia, there is a step, but
> ...it really depends on the aircrafts design. For instance, in
> the simple axial flow jet, increasing the speed injects a greater increase
> in air which demands more fuel which produces more speed....... So, when
> number four gets sloppy in a four-plane turn at critical altitude and he's
> at full throttle, he dives, picks up increased speed (temporarily) and
> rejoins. The PBY-5A Canso could be flown at about 5 different speeds,
> depending on where you stopped trimming for top speed - at the same power
> settings. A number of aircraft have differing horizontal tail lift
> characteristics and can be flown at various Riggers' Angle of Incidences
> because of the "flying tail' - like the Europa.
> Just because some haven't seen it, don't mean it ain't so.
> Here we go......
> Ferg A064
>
> ----- Original Message -----
> From: Fred Fillinger <fillinger@ameritech.net>
> Subject: Re: Inflight Variable Pitch Props
>
>
> > 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.
> >
> > A Google.com internet search I did only debunks it, if one ignores the
> > positive comments on non-authoritative pages like discussion group
> > archives (and floatplanes of course). Avweb.com has an article by
> > Linda Pendleton, who works for King Schools (videotape flight
> > training) and author of "Flying Jets." Myth she says, and proves so
> > in a Mooney. A paper by Jim Irwin, V.P. S-Tec Systems (the autopilot
> > people) says "old wives tale." Another posits a possible source for
> > this "urban legend," namely inefficient designs from the "old days"
> > where cruise wasn't too far along the front side of power curve, and
> > it seemed you couldn't get there unless you zoomed down at it.
> >
> > Can't afford to bet on the issue, though. Homebuilt aircraft builder,
> > you know.
> >
> > Regards,
> > Fred F., A063
> >
> > > Tony Krzyzewski wrote:
> > > ...
> > > UBD maxes out at 137kias, 65% cruise is 120kias though you
> > > can get her onto the step a bit more if you are lucky and
> > > it'll creep up closer to 125kias.
> > > ....
>
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