Back to the future! i'll explain that:
When we were still covering hang gliders with ploy traps DuPont invented a poly material that was tough in all directions and had less stretch than a poly trap. It was called Tyvek. Joe Faust first brought it to my attention. I called DuPont to find out how I could buy some and was told that it was only available from them and i would need to buy a railroad car load as minimum purchase - price in the thousands of $. That was the end of my interest in Tyvek.
Now to the present: We now see it on most new construction of buildings and homes. My local Home Depot has 9 rolls in stock. There is also a fantastic tape, that i have used for many other things, that is designed to stick to it very well and the tape stands up to UV radiation for years.
So, last night I looked it up on the web to see what size it comes in. It's a roll that is 9 feet wide by 150 feet long (1350 sq ft). The material weight is 1.8 oz per sq yd so on my glider this adds up to a total of about 3.4 lbs of sail. Very much in the ball park of a light dacron sail.
I am now seriously considering making the sail for the first go around on the Puffin out of Tyvek. At 9 ft wide it will only require one short span direction seam near the center and the center joining seam. Tyvek tape will do that job.
Since first flights will be at Dockweiler it will hark back to a long tradition of plastic tarp gliders flown there. However, the frame won't be made of bamboo (unless Wills waits too long to get me the aluminum).
Still waiting for the aluminum
Frank C.
- Basic Trainer, sail & battens design.jpg (324.29 KiB) Viewed 6490 times