My very limited experience with Spectra (Dyneema, etc), about 50
launches, was very positive. I've driven maybe 2000+ launches with steel
cable. One of the nicest things about the synthetic lines is that they
have very little tendency to throw themselves into a tangle when there
is a sudden release of tension on the launch (cable break or simulated
cable break). Also, a drum of synthetic has much lower inertia than a
drum of steel cable so it's easier to control.

My only problem, and a very slight one at that, with the synthetic line
is that it doesn't sag under it's own weight on launch. The sag of steel
cable is a prime indicator of tension. Too much sag means you need to
add power, too little means you have too much power on. With the
synthetic, this clue is lost. It just looks like a laser beam from the
winch to the glider.

I still miss the winch...

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