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  #218  
Old July 11th 05, 03:13 PM
Don Johnstone
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A couple of points. After the first launch a weak link
is no longer at it's design strength, this reduces
with every launch. After 20 launches check the hole
in the centre of the tost weak link you will find it
is slightly oval and if you run your fingers along
the edges you will feel a depression. Unfortunately
many weak link 'holders' do not allow this check to
be made easily. A weak link will eventually break just
through 'normal' use if it is not replaced.

Up to the point at which the cable is at an angle of
more than 60 deg to the ground it is best if the cable
is released under full tension and the result dealt
with as a launch failure. What should be avoided is
lowering the nose early in the launch and pulling the
release especially if the launch is fast. It is very
easy for the parachute to open and fly and glider catch
up with it in those circumstances. I have seen the
cable wrapped round the wing when a pilot lowered the
nose because he was going to enter cloud and then pulled
the release. It should always be the other way round.
Lowering the nose when the glider is directly over
the winch, at the top of the climb is fine.

At 12:48 11 July 2005, Mark Newton wrote:
In article ,
'Bert Willing' wrote:

I have seen (from the ground) quite a couple of critical
situations
resulting from fatigued weak link breakage, and I
prefer to watch angle of
attack and speed, and pull the knob myself if necessary.


With all due respect, Bert, if a weak link breakage
creates a 'critical'
situation, then the pilot has a training issue which
needs to be
resolved. Sounds like some cable break practice is
in order.

A launch isn't supposed to be a hazardous maneuver.
If there's -any-
stage during the launch where someone wouldn't be comfortable
with
the cable breaking, they need to find an instructor
and get some
remedial training.

- mark