Hi guys,
I believe the issues we see being blamed on piloting and maintenance are
a soft argument as most of us who build and fly are regarded as very
responsible. But, the previous class of 601s had nearly none of the
history of failures exhibited by the latest XL model.
The logical conclusion must be made that the margin of strength, from
fatigue to failure was brought nearer by a changes to a shorter
center-spar, reduced height wing spars, a main spar slightly angled off
from the direction of loading. These are significant changes that can go
without complication for many hours, but might possibly be overcome by
time, max loading, convective air and or minor mishandling of the
aircraft. There may even be a problem with minor variability of
construction affecting this narrower safety margin, but it too would be
very hard to find. Its still too early to get into a fault finding game.
The RVs had a similar problem with wings occasionally breaking off and
they made a fix that allowed them to survive and continue, painful as it
was.
If I owned an XL, Id be very happy to make the modifications and accept
the improved strength and original intent of loading. The reported cost
seems very reasonable.
Because the design is the intellectual property of Zenith, I really hope
they are able to survive the legal implications.
Do fly safe guys,
Larry McFarland 601HDS at www.macsmachine.com <http://www.macsmachine.com/>
