Originally Posted by Crash one
Something lacking in the design department here. If they survive & become work hardened they are no longer the "weak" link they are supposed to be. How could one be re-calibrated to the next strength up? Prob impossible without breaking it to find out.
If weak links are designed like this then they are worthless, dangerous, chance of ripping the tow hook out of the glider. I would suggest some thought be put into them.
I believe they are just a short length of steel plate of varying thickness to suit the weight required. Bad idea.
Don't be ridiculous. There are hundreds of thousands of winch launches every year in Britain alone, I've never heard of a tow hook being ripped out of a glider. I know sweet FA about metallurgy but I'm sure that the manufacturers have taken such things into account.
Mary, some places
do use rope on the winch. Skylaunch visited us a while ago to set up a winch for a continental club, equipped with a nylon rope. Also, from John Marriot's "Aerotowing Guidance Notes":
If the glider brakes are open, do not signal immediately unless absolutely necessary, try to get the glider to a safe height if possible, then signal.