DASSAULT NEW GENERATION OF FRAGILIZATION
Guy Drouet, Franck Salis, Dominique Carme
All Dassault Aviation aircraft up to Mirage 2000 have been
equipped with fragilization device, based on pyrotechnic
fragilization points and expanding tubes which create local cracks
on the cast transparency. Efficiency has been broadly demonstrated,
but it is not applicable to the Rafale stretched acrylic canopy,
which is not prone to crack.
So Dassault Aviation developed a system based on pyrotechnic
cutting cords, which proved to be much easier to install and
maintain. Hence we have been awarded by the French MoD a contract,
to study its application to previous aircraft, in order to cut down
recurrent costs.
The first phase was to define a common type of cords, with
shrouding, suitable for all types of transparencies in
service.
Validation is based on an extensive static test program, to prove
feasibility, and check similar cracks distribution, and energy
released in the transparency, compared to previous design.
Full qualification has been achieved through high speed tests on the Alpha-Jet sled, which is the worst case because of its most pitching front canopy.
The program has been successfully completed now. Application has started for AAF, and this more attractive design is currently proposed for export.
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