This thread is boring...what's the lowest heigght one should start an
aerobatic manoeuvre? Should one use the rudder when rolling in a clover
leaf loop below 500ft?

Jim


At 15:29 04 August 2008, Roy Clark, \B6\ wrote:
At the beginning, Paul wrote:
is feed in rudder. On his 1-5 list of making a turn in a glider, #1 is
rudder (as it's own separate input). While this may be aerodynamically
acceptable practice for a 2-33, it seems a recipie for disaster in
other ships to begin a turn by intentionally skidding. Since in a
pinch, one has a tendency to revert to instincts that were first
learned/practiced (right OR wrong), I see this as a setup for possible
future problems.
Since I have issues with this, I want to gather some other opinions
(particularly those of other CFI's) to help present a case to
possibly get this corrected. He holds little value of MYopinion, so I
group.

Paul,

I share your concerns about this. Not a CFIG, but I was not taught
this way of turning and none of the CFIG=92s on multiple BFRs or check-
out flights in the USA =96 WA (4 different sites), AZ (2), CA (6), NV
(2), NM, CO, FL, PA, MD - or elsewhere, Canada (2); Germany; or
England (2) suggested his method.

So, I checked my home soaring library and found the following that
includes some =91name brand=92 opinions:

=93For most beginners, making a turn is the most difficult step in
learning to fly. Two controls have to be operated together to perform
the evolution correctly. The rudder bar must be pushed back and the
stick tilted over. These movements must be made in coordination if the
glider is to be banked and turned at the same time.=94
- Edwin Way Teale, The Book of Gliders, page 205, 1930

"Think it through. The turn is to be to the left. Apply the bank to
the wings with the stick, a gentle pressure in that direction. At the
same time apply a little left rudder. Don=92t kick it, apply pressure.
These two movements are simultaneous. It=92s like the arm motion and
foot work in tennis. If the timing of one or the other is off, it=92s
the fence the ball goes over, not only the net."
- Richard A. Wolters, The Art and Technique of Soaring, page 80, 1971

=93Unfortunately, this turn-by-rudder idea is hard to kill. It has away
of re-creating itself. It is often used to explain the airplane=92s
controls to high school kids or general magazine readers=97simply
because it is easy to understand for nonflying writers and readers,
teachers and pupils. It recreates itself also in the pilot=92s own
nervous system, even when after he should really know better. This is
because you can use the rudder with apparent success to =93steer=94 the
airplane, that is, to make small changes of direction, in straight
wings-level flight. As explained elsewhere, this is a faulty technique
of flying straight, but it is widely practiced, and if you use you
rudder 30 times a minute to steer the airplane a little bit more to
the right and a little bit more to the left, you are bound to use it
also when you want to steer he airplane a whole lot to the right and a
whole lot to the right and a whole lot to the left!
But the rudder can never produce a turn. It cannot =93start=94 a turn
or
even =93help the turn get started.=94 It cannot =93stop=94 a turn or
even
=93help the turn get stopped. The only effect the rudder can ever
produce is yaw. Yaw, in this sense, means practically the same as
=93skid=94 or =93slip.=94 The airplane=92s nose is swung to one side or
ano=
ther
while the flight path continues substantially unchanged, so that the
airplane slices through the air slightly sideways. Yaw is not a turn.
A turn, a clean nice curving of the flight path without skid or slip,
cannot be produced by the rudder but is produced by entirely different
means. The rudder is quite unnecessary for the turn. Some airplanes
haven=92t even got a rudder, but only a rigid vertical fin, and yet they
turn. And the birds don=92t even have a vertical fin!
All this will be made clear to a patient reader. But first we must
kill the turn-by-rudder idea. Only when that is done can the reader=92s
mind be really receptive to the story of how the airplane really does
turn.=94
- Wolfgang Langewiesche, Stick and Rudder: An Explanation of the Art
of
Flying, pages 192-3, 1944

=93Now that the turn and its forces are understood, the student should
be shown by applying pressure to both the stick (aileron) and rudder
in the same direction.=94
- Schweizer Soaring School Manual, Revised Edition, page 26, 1982
[Would
apply to that 2-33.]

"To enter a turn:
1. =85.
2. =85.
3. While watching the horizon, apply stick and rudder together in the
desired direction."
-Thomas L. Knauff, Glider Basics: From First Flight to Solo, 4th Ed.,
page 52, 1987

=93Assume that a turn to the left is to be made. The bank in that
direction is started with left stick and left rudder together.=94
- Carle Conway, The Joy of Soaring, page 17, 1989

"Roll into the turn with aileron and, at the same time, use sufficient
in-turn rudder to prevent adverse yaw and any slip."
- Derek P.W. Johnson, The Glider Instructor=92s Workbook, page 21, 1993

"Going into the turn
Before turning to the right, for example, first look out to the left
and then round as far as possible in the direction of the turn =96
particularly behind the wing.
If it is clear then =96
- look ahead over the nose
- roll the glider using aileron and stick together"
- British Gliding Association Instructor=92s Manual, 10:2 1994

"Entering the turn
Lookout.
Look over the nose of the glider to check the glider=92s attitude and
and bank angle.
Apply bank by using aileron and rudder together."
- Ken Stewart, The Glider Pilot=92s Manual, page 46, 1994

"Going into a turn
1. Look around for other aircraft.
2. Look ahead and hold nose in correct attitude.
3. Apply the bank =96 move stick and rudder together"
- Derek Piggott, Beginning Gliding, 2nd Ed., page 42, 1995

"After release from tow, your instructor will demonstrate adverse yaw
by using ailerons to bank the glider without applying simultaneous
rudder. The glider with yaw in the opposite direction from the
intended turn at first. You instructor will then demonstrate use of
the rudder in coordination with the ailerons to counteract adverse
yaw."
-Bob Wander, Learning to Fly Gliders: A Flight Training Handbook and
Syllabus,
page 19, 2003

"It is important rudder and aileron inputs are coordinated during a
turn so maximum glider performance can be maintained. If too little
rudder is applied or if rudder is applied too late, the result will be
a slip. Too much rudder or rudder applied before aileron results is a
skid. Both skids and slips swing the fuselage of the glider into the
relative wind, creating additional parasite drag, which reduces lift
and airspeed. Although this increased drag caused by a slip can be
useful during approach to landing to steepen the approach path and
counteract a crosswind, it decreases glider performance during other
phases of flight."
- U.S. Department of Transportation, Federal Aviation Administration,
Glider Flying Handbook, page 3-12, 2003

Seems pretty consistent from 1930 to 2003 with the method I was
taught.

Perhaps that SSA =91Master=92 CFI has stronger soaring literature
documentation than the above to support his opinion. Were one of his
pupils involved in an injury incident, I=92m quite sure he would need
it.