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Old March 28th 04, 12:51 AM
John Firth
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"Bill Daniels" ) writes:
"W.J. (Bill) Dean (U.K.)." wrote in message
...
In discussions about winch design and construction, I think not enough
attention has been given to protecting the driver from the cable.

This is a report about one accident (B.G.A. 1991/20):

after reading this I feel lucky to be alive, let alone uninjured.
In my first two years (58,59) at the Bristol GC I did a lot of winch driving
in a winch cobbled together from a lot of surplus stuff. Manual dry clutch,
tired old Ford V8 side valve, lightwieght mesh screen, open side panels
and a guillotine fo doubtful capability. Cable breaks were a 10%
probability; I thought contest flying was riskY!

John Firth
old no longer bold etc.

"At the top of a normal winch launch the weak link failed and a fast

moving
"snake" of cable fell onto the winch driver's cab. It found its way
through a narrow aperture in the wire mesh guard and hit the driver about
the head, nose, jaw and teeth. Fortunately he was only marked and not
badly cut. The club proposes to modify the guard."

I know of another case where a "snake" of cable escaped from the drum,

found
its way out of the drum cover, broke a window in the winch cab and

attacked
the driver. It then disappeared back onto the drum leaving him to work

out
what had happened. The driver was uninjured with torn clothing, he has

not
driven the winch since. The drum cover has been improved.

In a third case the wire broke, then whipped back behind the winch and
attacked the winch driver's car parked behind the winch (with the front of
the car towards the winch). It trashed the rear of the car and then

wound
back round and broke one of the front door windows which was up. I saw

the
car afterwards, I would not like to have been sitting in it when this
happened, especially if it was a warm day and the window was down! This
particular winch driver was very experienced at winching.

All these incidents happened so quickly that there would have been no

chance
to take cover.

These dangers are much greater than most people realise. They do not
happen very often, but are you prepared to take the risk?

W.J. (Bill) Dean (U.K.).
Remove "ic" to reply.


Bill, excellent point!

I have always considered the winch drivers job to be more dangerous than the
glider pilots. I tell people that each time I reach for the throttle, I
think about the 300 pounds of steel wire that is about to come straight at
me doing 70 MPH.

Steel wire mesh or screen is totally inadequate to protect the driver. The
winch cab windows should be 3/4" polycarbonate (Lexan) which, I'm told, will
stop a 9mm bullet fired point blank. Yes, Lexan will get scratched
eventually but it's not that expensive to replace. The rest of the cab
should be at least .125 inch steel sheet.

Spectra will reduce the danger somewhat but the rest of the hardware will
still be there and present the same dangers.

I would prefer a winch cab that is armored, weather tight and air
conditioned.

Bill Daniels



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