On 2007-06-10 22:41:49 -0400, "Maxwell" said:


wrote in message
ups.com...
There was a thread a while ago about how not only could one stay with
the force into the seat, but actually maintain 1 G straight into the
seat through a roll. If one is flying coordinated, keeping normal to
the airplane makes sense. Those how fly aerobatics have a different
set of criteria. For what it's worth, watching the in cockpit cameras
of some moderatedly skilled pilots, like the Blue Angels, shows them
"upright" with respect to the airplane except when G forces sling
their heads around, but they do fly coordinated most of the time.

But what do they know?


That is either untrue, or real misleading. The Blues fly with a different
purpose, keep the aircraft on trajectory. When they are flying a knife edge,
they are hardly coordinated, as with many other maneuvers.

A 1g barrel roll can be done, but the required trajectory of the aircraft is
not going to be one that is necessarily eye pleasing for ground
demonstration purposes.

Actually, when the Blues or anyone else is in knife edge, they are
indeed in coordinated flight. You hold the aircraft in knife edge with
top rudder and forward neutral stick; this control pressure combination
has to be perfectly coordinated to maintain knife edge.
You are confusing coordinated with meaning the control pressures must
be complementary which is a common mistake often made.
The first lesson we teach in aerobatics is that "coordinated" has
absolutely nothing whatsoever to do with the controls not being crossed.
Actually, any good flight instructor will teach this to a new primary
student during the first hour of dual :-)
Dudley Henriques