"Bruce Greef" wrote in message
...

The winch has plenty power - but we have one runway that is only 1300m,
stony and uphill to boot. At the other location we have a less powerful
winch (220Hp), but 2000m to launch on. It is also hard stony ground
though.

So - we use single strand wire, that does not like the heavy gliders. The
Grob 103 Twin Astir is notorious for breaking the wire. Multistrand gets
eroded too quickly by the terrain. I don't know whether UHMWPE
(Spectra/Dyneema) would be any use on this - or would get cut up by the
field.

Bruce

The data on UHMWPE is still somewhat limited but what data there is suggests
that it outlasts both solid and stranded steel by a wide margin. A factor
seems to be that it doesn't bear down on the rough ground like steel does -
it just floats along the top so it doesn't abrade.

How about a stronger winch on your 2000 meter runway? That could produce
1000 meter AGL launches

Bill Daniels