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Old October 6th 08, 04:18 PM posted to rec.aviation.homebuilt
Tim Ward[_1_]
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Posts: 49
Default Primary Glider Drawings


"Bill Daniels" bildan@comcast-dot-net wrote in message
. ..
snippage
Let me throw in a slightly controversial idea.

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. In spite of this, there is an
instinctive reaction among most glider pilots to inversely relate L/D and
safe handling qualities.


In a soaring environment, I think you're right. But that is not the
environment veeduber is proposing.

He's proposing a cheap "hook" to capture the attention of teenagers.
Teenagers who might not have two grand or so to shell out for glider
lessons, but might well have some sweat equity to invest in building
something that actually flies.

For this target group, it has to be something that goes together pretty
quickly. If it takes a thousand hours of construction, it isn't likely to
get started, let alone completed.

For veeduber's purposes, I think he will have achieved part of his goal if
it gets even half built. Kids will be using their heads and their hands to
solve problems.

For this environment, it's not performance that counts, but energy. With a
fairly draggy airframe, you can limit the amount of energy available to
damage the pilot.

Somewhere on Mike Sandlin's site, he remarks on this, limiting the energy by
how far up the training hill you drag the glider.

snippage

"Primary gliders" were an expedient developed in an environment that

lacked
adequate two-seat trainers. They were abandoned with great relief as soon
as usable 2-seater trainers became available. Today, there are a great
number of excellent 2-seat trainers and qualified instructors. Only a

fool
would try to learn flying in a "Primary".


I can't entirely disagree, but people learn to fly hang gliders, with
similar performance limitations, every day.
There is some tandem instruction available, and that's good. But in
general, it's not the instruction process that kills people.
A two-place primary under 155 lbs might sneak in under USHGPA's tandem
exemption, here in the U.S. Maybe.


Tim Ward