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Old April 14th 04, 04:43 AM
Ernest Christley
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Robert Little wrote:
It is true that our fabric is heavier than the choices that are now
available. It was originally designed for agricultural aircraft, Stearmen
to be exact. It weighs 3.6 oz. and uses less dope than Grade A cotton that
weighs 4 oz. So technically, it weighs 17% less than the original fabric on
J-3s, BC-12s, and etc. So with 35 yards for a average project, the total
weight difference from a temporary dacron fabric of 2.4 oz per yard and the
less expensive, but 200% stronger, permanent glass fabric system doesn't add
up to all the negative talk about weight to the economists.


So, why do you not offer the process in a lighter fabric?

The application that I'm looking at is an elevon that is hinged from its
leading edge. The top speed is limited by the possibility of speed
induced flutter in the elevon. A lighter elevon corresponds to a higher
top speed, so this is one of the few places on this airplane where I'm
actually concerned about ounces ('cause flutter stories scare me more
than all the others).

It's late, and way past my bedtime, but 3.6oz FG sounds like a lot more
strength than is needed and way stronger that the specified fabric.
I'll do the math tomorrow. But is there a reason that a lighter fabric
can't be used? Since the fabric is 200% stronger, why couldn't you
replace the 2.4oz Dacron with 1.2oz Razorback?

BTW, I haven't seen any prices listed, but LESS expensive than Dacron?
Dacron is fairly cheap as far as coverings go.

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