Hello John,
I must admit it did not occur to me to check ADs when speculating on
flutter. AD 50-07-01 was issued
at the very end of Ercoupe production, and had absolutely no effect on
prior in-flight trim wire failures.
In retrospect, I would revise "...half of the active fleet..." (below)
to "perhaps 10-20% of the active fleet...". ;<)
The most appropriate and well intentioned directive is still less than
a magic wand. Meaningful and continuous 100% compliance is an
aspiration seldom, if ever achieved in the field. Once aloft, it's
not about being right (in compliance) or wrong (when something fails in
flight).
The original and exemplary safety of Fred Weick's design is enhanced
not only by the springs & stop and the AD, but also by sharing the
knowledge necessary to better deal with in-flight emergencies like
flutter. Both you and I, in our own ways, seek to make flying Ercoupes
fun, practical and safe.
Happy New Year
WRB
--
On Dec 28, 2008, at 12:40, John Cooper wrote:
I would speculate, human inertia being one of the more common and
powerful forces existing, that more than half of the active fleet
still DOES NOT HAVE the trim stop and spring modification. While said
modification obviously adds a measure of safety in excess of it's
nominal cost, Ercoupes without it should NOT be considered "accidents
waiting to happen".
Guys:
AD 50-07-01 *requires* installation of the springs and stops.
What more can I say?
John Cooper
