Pretty sure it's in the manual.
(Not sure if it's manual for hook or glider!)

For a club glider assumption is 4 activations per launch, once to hook on
to tow to launchpoint, once to release when at launchpoint, once at start
of launch, once at top of launch.

So hook should be overhauled every 2500 launches or so.

Overhaul of our hooks normally costs 150-200 Euro, so about 0.16 Euro a
launch (2-hooks)

If you don't tow the glider around on the hooks you may be able to make a
case for only 2 activations per launch so saving yourself the vast sum of
0.08 per launch

KN


At 16:23 28 January 2014, 150flivver wrote:
Those of you with TOST hooks, how do you track the number of times the
release is activated? As I understand it, the mechanism has to be
rebuilt
when it's been exercised 10,000 times due to the main spring getting worn
out.