Larry, Hal --
Thanx for your input, especially as it based upon
actual experience. It sure sounds like plastic is
just fine for wing spars, but not brake lines <g>!
However, I do want to use aluminum all the way
---From the master cylinders to the brakes. On the
tri-gear, the master cylinders are of course in
the footwell, and I don't see any way to
adequately inspect those nylon tube fittings other
than for obvious leakage. And that presumes I can
get down in there to even install them properly.
With metal tubing, it's guaranteed airworthy if
the nut is tight.
I understand that flexible Aeroquip hose at the
caliper is the best solution, but there's no
weight penalty to merely sub aluminum for the
nylon. There will be a weight penalty in the
Aeroquip hose, with the additional fittings to
marry to the nylon. I know that on some
production fixed-gear A/C, they run aluminum all
the way to the caliper, 5052 probably, and the
only long-term implication I've seen is sometimes
it hair-line cracks a Cleveland caliper where the
AN fittings get tugged at once too often by the
stiff tubing, causing minor leakage.
I wonder if the softer 3003 would work here given
the lesser pressures of duty in an A/C of Europa
weight. It's also easier to route (very
circuitous), and I probably can loop it easily
where it connects to the caliper.
Do you guys, or anyone else out there know?
Regards,
Fred Fillinger, A063, N3EU
Larry Graves wrote:
> Our suggestion is to terminate the plastic or nylon brake lines just above
> the brake caliper and join with a union fitting to an Aeroquip-type brake
> hose of the sort that is steel braided tubing wrapped in a rubberized cloth
> braid, rated to 3000 psi.
Hal Perkins wrote:
> Whilst flying a PULSAR XP, I had MATCO brake failure due to hard braking.
> The heat so generated was transmitted from the brake pads through the metal
> parts to the union onto which the clear plastic hosepipe fitted. This
> softened the pipe sufficiently for it to 'blow-off'.
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