Very well said, Larry! I wish I woulda read yours first before spending the time
to write my own!
Rick
do not archive
-----Original Message-----
>From: LarryMcFarland <larry@macsmachine.com>
>Sent: Nov 16, 2009 4:27 PM
>To: zenith601-list@matronics.com
>Subject: spar and wing mods
>
>
>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/>
