Leading Turns With Rudder

"sisu1a" wrote in message
...
I feel compelled at this point to add that this guy does not promote
stomping the rudder or other outwardly unsafe flying habits and is
absolutely fanatical about keeping the string straight, to the point
of obnoxiousness. He would not accept my explanation of mildly
slipping during thermaling ala' Holighaus/Johnson on a flight last
year, outright rejecting it on principal (he was sure I read the
article wrong or remembered it incorrectly).

I also want to add that my concern is geared toward what ab-initio
students should or should not be taught, as it is very hard to unlearn
something, no matter how wrong. As far as I understand the human
brain, it will most likely revert to these early lessons when/if a
'situation' arises and stress levels are very high.

I certainly don't think he should have his ticket yanked by any means,
I just have my own reservations about the soundness of *possibly*
instilling reflexes into people that can potentially be dangerous if
reverted to at an inopportune moment. This forum seems like a good
place for this discussion, to see how others more qualified than I
weigh in on the subject before making it a campaign and I thank
everyone thus far for their thoughtful responses.

-Paul

I'm uncomfortable with teaching "lead with rudder" to primary students. In
fact, aerodynamically, there is no need for rudder until adverse yaw
manifests itself so both rudder and aileron should be applied
simultaneously.

Where this idea comes from, I think, is that it often FEELS like rudder
input needs to come first. This is because most people move their feet
slower than their hands. If your brain tells your hands and feet to move at
the same time, the hands will move first. If you consiously try to move
your feet a fraction of a second before your hands, it's likely they will
move at nearly the same time.

The problem with "institutionalizing" the rudder-first idea is that as
pilots gain experience, their hands and feet will start moving in
synchronization leading to real rudder first action and inadvertant skidding
turn entries.

I tell students to move the rudder and ailerons at the same time but to
expect that, at first, their sluggish feet reactions will make it feel as if
they need to use the rudder first. Later, when they have more experience,
it will feel like they are moving them at the same time.

So much for inadvertant skiding turn entries. It is actually an advantage
to deliberately skid turn entries with some gliders. If the glider has a
lot of dihedral, there will be a strong yaw-to-roll coupling effect which
adds to the roll effect from the ailerons. Slightly skidding the turn
entries with my Nimbus 2C will cut a second off the 45 degree right bank to
45 degree left bank turn reversal which is significant in a 20m glider.

BTW, the effect of the Holinghaus/Johnson slipping turn is not to achieve
"fuselage lift" but to use the dihedral yaw to roll coupling to hold off
overbanking while keeping the ailerons centered. Centered ailerons keeps
the wing profile intact tip to tip resulting in a greater rate of climb. It
also has the added safety benefit that if the glider stalls it is likely to
drop the high wing giving the pilot an additional second or so to recover
wings level.

Bill D