HL Falbaum wrote:
"Eric Greenwell" wrote in message
news:B341h.1741$B44.1220@trndny07...
Gary Evans wrote:

The ASH failures may be due to another problem that
being storage. The gates preventive maintenance manual
clearly states that the stored belts should not be
subjected to bending beyond that which is defined as
the minimum pulley diameter as it may damage internal
cording resulting in premature failure.
The belts are obviously designed to be used in a straight
line without twisting which may be the reason why twisting
is not specifically identified as something to be avoided
in the Gates manual.
The ASH drive system puts a 90-degree bend into the
belts when the engine is stowed into a relatively hot
environment. If you explained these failures to a Gates
engineer and showed them the drive design they may
point out that twisting in heated storage could be
a contributing factor.

I have no knowledge of what Schleicher's discussions with Gates have been;
however, the ASH belt breaking problem is a recent one. Older belts don't
break - it's the NEW belts that are breaking. My belt is 12 years old, the
engine has 114 hours on it, and at least 600 starts. When I discussed belt
life with Martin Heide (the "H" in ASH) about 3 years ago (which was
before the current problem), he said several 26 Es had been in the shop
for the 250 hour motor inspection, and all belts were in good condition.

It could be the twisting has become a problem due to the change in belt
construction that Schleicher says has caused the recent problems, but I
doubt it. When a belt breaks with only 5 or 10 hours on it, it doesn't
seem long enough for degradation to occur. I suspect the culprit is also
shock loading, but that's speculation on my part, since I haven't
discussed it with the factory or Gates.

In any case, a prospective buyer might want to discuss the issue with
Schleicher, and remember that a glider ordered now won't be delivered for
many months, during which the problem is likely to be solved, if it isn't
already.

--
Eric Greenwell - Washington State, USA
Change "netto" to "net" to email me directly

"Transponders in Sailplanes" on the Soaring Safety Foundation website
www.soaringsafety.org/prevention/articles.html

"A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Is the ASH-26 a Walter Binder installation design?
It seems so different than the other Retract-Engine Sailplanes.

Hartley Falbaum
DG800B "KF"

IIRC, Binder does the Solo-based DG and SH designs, and I think
some others (maybe Eta and the ASH-25 EB derivative he produces)...
I don't think he's involved with the Midwest installations in
Schleicher
products.

Antares was developed entirely independently of the other designs.

Best Regards, Dave