>Miles,
>What guarantee is there that you will not be one of the pieces that choose
>NOT to remain part of the aircraft after such severe loads have been applied
>to it upon deployment? I envisage a BRS beautifully depositing 3 reinforced
>anchor points unscathed on the ground below the point of deployment. Does
>the fuselage require reinforcing between the anchorpoints?
>
The usual parachute makers guarantee? money back if it doesn't work?!
Actually, it'll come as no surprise that we are paying some attention to
this... Effectively the anchor points are in the cockpit module, tied to the
bottom fuselage shell. BRS tell us that the "usual" deployment loads are in
the order of 2-3G, so we are working to a safety factor of +100% (6G) for
each attachment point. Barry mellors says no problems, and in fact the
inserts and fittings will have an additional safety factor built in. No
additional reinforcement required, other than locally around the inserts to
make sure that they are well tied in - and we do have to prove this to the
PFA via FEA.
Part of the deal is a lawyer induced placard prohibiting deployment above
143kt (as if....) but unofficially I have been told that they are 99.999%
certain that it will be OK well above Vne - and the deployment loads will
still be below 6G.
The ultimate arguement of whether fitting a ballistic parachute is
worthwhile can, of course, be answered by around 500 people who have used them.
Miles
|