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Old June 30th 06, 11:52 AM posted to rec.aviation.soaring
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Default Puchacz shock cord (bungee) failure

Another thing you might like to consider is doing away with the Puchacz
original mainwheel & brake which have two severe irritations (in addition to
the one you describe):
1. the brake is a bugger to adjust and a bugger to keep operational in a
dusty & gritty environment, and
2. the valve for the tyre is located inside the mainwheel hub which is so
inconvenient that it is a disincentive to people checking & pumping the tyre
pressure up when required.

You can overcome both these aspects by installing the hydraulic disc braked
wheel kit for the Puchacz from Tost which we have found to be a really good
mod to do. The only hassle we have had with it in four years is that
recently we lost presure due to leakage at the master cylinder to brake hose
junction. This was almost certainly due to the brake hose end continuously
flexing as the undercarriage moves. The fix we think is to install a
support to hold the start (ie the master cylinder junction end) of the brake
hose very firmly and resist the flexing.

While I am contributing some ideas to others, perhaps someone out there in
Puchacz land knows and can advise what the fix procedure is when you get to
the stage where the freeplay at the tip of the horizontal stabiliser exceeds
limits?

Cheers
Roger Druce, Australia

wrote in message
oups.com...
This weekend one of the bungee cords that serves as the shock absorving
element of the main landing gear of our SZD 50 Puchacz was found to be
broken. The symptom was a weird noise coming out the main wheel area
while the plane was taxiing back for a relaunch. The plane had a
uneventful landing moments before. Upon inspection the broken bungee
was aparent at the brake side of the main wheel. Seems that the brake
lever that goes up through the landing box has caused a premature
failure of the cord by repetitive attrition. Therefore, I advise all
Puchacz operators to inspect for the status of the bungees specially
the left one (looking tail to nose) each flight day for premature
wearing around the brake lever.
Also, the Puchacz can land with two people on just one bungee and
nobody will notice it...as long you grease in....