> -----Original Message-----
> From: Michael Derry
>
>
> Dear All
>
> I understand that it is SOP to have a heavy trace at the end
> of the wire
> near to the glider for winches using wire.
>
> The reasons would no doubt include:
> -to stop the rope bunching up into the wheel well in case the glider
> overuns the cable on launch;
That's the main reason but stiffness is what you want rather than heaviness. It does/can happen and with winch (and auto tow) the CofG hook is near the wheel/skid so the chance is greater of a hook up on these types of launches. This is totally irrespective of the cable material.
> However if the rope used is not too heavy and can be wound in quickly
> then no recovery chute will be required for some locations. Adding a
> trace and a chute adds extra hassle and complication. If this
> imposition
> can be removed without compomising safety it would be great.
Note that a hookup will only occur near the start of the launch. How you recover the cable at the end of the launch is a different issue.
For many years Adelaide University gliding Club in SA did not use a drogue. They had power lines nearby and a floating cable was a bigger issue. They still used a stiff trace (and a bright coloured strip of material instead of drogue) on their (approx) 5mm stranded steel cable.
> It is not SOP to use a trace for the following to my knowledge:
> -aerotow;
The release used is closer to the nose and so less likely to get tangled on the wheel if the glider over runs. Also the tug can release quite easily (or they can even land together at a pinch) and the 60m or so trailing from the airborne glider is not such a big deal as say 300 m of winch cable.
> -autotow;
From memory, the autotow operations I have seen in Australia DID use a stiff trace (and drogue). But it was a long time ago.
> -bungy launch
An open hook at the nose (and large diameter ring) should be used, less likely to get caught up as per aerotow. Also bungey hasn't seriously been used in Australia.
>
> Why is winching more in need of a trace than the other launch
> methods ?
>
> Are there any groups out there who use rope for winching and
> do not have
> a trace and a chute ?
A trace is not such a big deal. Remember you also have to put the weaklink somewhere. Unless you put them directly on the rings (which would probably bash on the fuselage bottom) you will end up with a de facto trace in any case.
I know various people around the world are always thinking of ways to improve winching ops, as should we all, but things like traces and weaklinks are lessons the gliding movement learnt long ago.
Regards
SWK
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