At 11:44 08 October 2019, Tango Eight wrote:
On Tuesday, October 8, 2019 at 3:28:04 AM UTC-4, Bruce Hoult wrote:
On Monday, October 7, 2019 at 5:07:25 AM UTC+13, Dan Marotta wrote:
I can roll up into a 90 degree bank and, if I don't apply up or
down=20
elevator, the plane won't turn.=C2=A0 The nose will simply knife
downwa=
rd.=C2=A0=20
So, am I clinging to something?=C2=A0 Think vectors and the vertical
an=
d=20
horizontal components of lift.
=20
If you are flying straight and level and then roll into a 90 degree
bank
=
while keeping the same elevator position then you will enjoy turning with
1=
G of centripetal acceleration. Until the nose falls through. And then
you'l=
l enjoy a 1G pullout (more as the speed builds).
=20
The only way you can *not* turn in that 90 degree bank is if you
actually=
moved the stick forward to the position that would give you a zero-G
pusho=
ver in level flight.

You haven't tried explaining this to a student, have you? :-)

Here's what really happens if you bank to 90 degrees while holding the
elev=
ator control in one place: the nose drops starts dropping the moment you
b=
egin to bank, the aircraft begins to accelerate and the g forces
increase.
=
There is -no- period of time that "you will enjoy turning at 1G of
centrip=
etal acceleration." =20
=20
Langewiesche (Stick and Rudder) has it right. Think of the elevator
contro=
l as your angle of attack control. Chapter one, "How a wing is flown".
Wh=
at a great place to start the explanation of the art of flying.

best,
Evan Ludeman


Funnily enough.... the assumption is made that the tail is acting with a
'downward' force, counterbalancing the mass ahead of the lift... with
neutral stability, the elevator actually exerts no force in pitch. And it
is also possible that the tail generates lift to support a rearward C of G
!!!
Banking to 90 deg and holding that angle changes the whole dynamic of the
weight and lift distribution, the fin and rudder now come out to play....
!!!