On Saturday, 25 August 2012 04:14:20 UTC+2, Andreas Maurer wrote:
On Fri, 24 Aug 2012 10:25:49 -0700 (PDT), "kirk.stant"
Snip

He did a winch tow in an ASW-19. The small ring of the tow cable was
not put into the tow hook, but jammed between the Tost release and its
steel attachement structure, creating an extremely strong and
permanent connection. Mistake of the student pilot who did the hookup.

Snip

- Check the ring if it fits perfectly (it should have just a little
play)

Snip

Cheers

Andreas

The club I fly at do the three checks for the CG hook for winch launching and a single tension release check for aero tows on the nose hook.

What I'd like to highlight is that you're the only person in this thread who has mentioned checking for play once the ring is inserted.

We have a standard "rattle check" on hookup.
If the ring does not rattle from side to side once hooked up it is assumed to be jammed from being inserted wrongly and is thus released and reinserted.

Paul