Winch Launch Stresses on Vintage Gliders

In theory the weak link is set to break at about twice
the maximum gross weight of the glider, but remember
that the glider also has to lift the weight of the
cable, the cable pull is a point load through the centre
of the fuselage, and if you hit a gust there may be
a momentary overload before the link breaks. As I said
before, use the correct weak link and don't exceed
the placarded maximum winch speed (lift, and therefore
stress, increases with the square of the airspeed).
Then you have two safety factors on your side.

Derek Copeland

At 01:06 24 January 2006, Brian wrote:
Someone please correct me if I am wrong,

But as I recall the weak link is supposed break before
it carries twice
the gross weight of the glider.
So during the launch the wings must lift at a maximum
the weight of the
glider plus up to 2 times weight of the glider through
the weak link.
So the maximum load you should be able to put on the
glider is 3G's.

I don't think I would want to fly a glider that could
not withstand
3G's.

Brian