US L-13 AD

On Jul 15, 6:53*am, Graemec wrote:

A whole lot of the field data is in. *The highest hour Blaniks have
always been in Australia
and a large amount of work has already been done. *The AD below was
issued in 1989:

http://2009.gfa.org.au/Docs/ADs/gfa%...0issue%201.pdf

In summary, it reports the major fatigue susceptibilities of L13s and
gives various ways of
extending the life. *The lower wing carry through plays a starring
role. *One solution involving
new Hi-Loc fasteners and an eddy current inspection schedule is laid
out in the AD's Appendix B and in the
earlier (1984) AD160:

http://2009.gfa.org.au/Docs/ADs/gfa%...0issue%202.pdf

This extended L-13 life to 12000hours and 50,000 launches - but it
does recommend that
aerobatics be limited to practice spins.

I don't know the current permitted Blanik life in the US and Europe
but the original LET were
reluctant to get involved in this 70s and 80s life extension work in
Australia. *I believe their
view at the time was that the glider was designed for 3000 hours
(IIRC ?) and that is where
it should stay. *I'd not be surprised if the current TC holders were
happy to see
most L-13s scrapped.

As Darryl says - don't hold your breath.

GC

I guess we in the Rest Of The World ought to pay a little more
attention to goings on in Oz. Thanks for sharing this.

-Evan Ludeman / T8