I am the engineer who did the load calcs and tried to route the BRS installation
efficiently for Miles' Europa. The rear mounted BRS was mounted to a structure
in the aft bay, the strops were routed forward to the engine mount hard points
and to the spar. There were shallow channels in the composite skins which
gave significant stress issues (local monolithic reinforcements, removal of
foam core) caused by the load offset and subsequent local bending moments. We
devised a suitable scheme, l think Miles did some tests of the layup, showing
the break-out force of the strop though the outer skin ply.
I did some work to determine the dynamic load factor caused by the chute
opening,
at that time BRS were developing their system.
The work was discussed with the PFA engineers who raised plenty of opposition
and
concerns.
I think the final straw came when the (unused) BRS unit had to be re-packed to
keep it in service. Miles and Ian abandoned the scheme and we pushed on with
the taildragger mods.
My own recommendation is that unless the primary structure of the aircraft is
designed
---From the onset for the installation of the BRS (generic term intended)
unit and associated load carrying strops, then forget it. Wear a parachute
instead
maybe.
--------
John Wighton
Europa XS trigear G-IPOD
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