Primary Glider Drawings
"Vaughn Simon" wrote in message
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"Bill Daniels" bildan@comcast-dot-net wrote in message
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Low L/D, taken in isolation, offers no benefit whatsoever in a trainer.
In fact, higher L/D is a safety feature that gets an inexperienced pilot
back to the runway after a bad judgement call.
I MOSTLY agree (see below) ...
In spite of this, there is an instinctive reaction among most glider
pilots to inversely relate L/D and safe handling qualities.
A high L/D implies a very slippery airframe. Unless any high L/D glider
trainer is very carefully engineered, a moment's inattention to any
nose-down attitude could quickly result in airspeeds beyond Vne.
Only a fool would try to learn flying in a "Primary".
I don't know that I go quite that far, but as I have said before, I
would not recommend a primary as a flight training aircraft. That said,
building one might be a great learning experience at the EAA chapter level
and flying it would be a great activity for the annual chapter picnic.
Vaughn
I actually have quite a bit of experience transitioning limited experience
pilots to high performance gliders. The most recent is a new partner in my
Nimbus whose only previous experience was in a 28:1 Blanik L-13. More often
it's a 2-33 pilot in a Duo Discus. My club trains ab-initio students in a
45:1 DG505.
Airspeed control difficulties in slippery gliders is often greatly
exaggerated.
Yes, they will have problems with airspeed control for a few minutes but not
extremely so. Mostly it's letting the airspeed oscillate in the 45 - 60
knot range while circling. They also tend to get a little fast on
approaches. Once they get a good handle on pitch attitude the problem goes
away. These "uber performance" gliders tend to have very effective
airbrakes with which to control excessive speed. Nothing dangerous here.
Letting airspeed increase unintentionally in a high L/D glider is no worse
than the inability to recover airspeed quickly in a low L'D glider.
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