guynoir wrote:

All dope and fabric systems use aluminum powder mixed with the finish to
block UV, which causes all fabric and dope to deteriorate. Dacron
"sails" as used on ultralights don't have UV protection, so they must be
changed every few years. The advantage of undoped dacron sails is
simplicity and weight savings.
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Dacron will last for twenty years or so if the plane is hangared when
not flying.

Outside, two years would be expected for sure.

There are also protectants that slow the effects of the sun on the
fibers.


--
Mark Smith
Tri-State Kite Sales
1121 N Locust St
Mt Vernon, IN 47620
1-812-838-6351
http://www.trikite.com