Very cogent analysis, Rob. Maybe it would help that everything would
happen in a sequence. Bending of the leg, breaking of bungee, partial
collapse of the frame's fat tubing where the cable hits, and then
finally the cable. The final whack to the airframe, if a beefier
safety cable survives, is thus after energy has been dissipated. Sort
of the way they engineer autos.
I agree on your final point, as also if everything lets go, slipper
clutch or no, the engine (gearbox integral with crankcase) could
easily become junk, especially prop strike on a hard surface rwy.
Airframe likely repairable, or so we hope....
Regards,
Fred F., A063
Rob Housman wrote:
>
> From the tri-gear manual, 30 May 1998 edition, page 29-12:
>
> Remember that the bungee does not provide the nose gear springing,
> the flexibility of the leg does this. The bungee is to allow a
> momentary overload to take place without over-stressing the anchor
> point.
>
> If this is the purpose of the bungee, any stress that is sufficient
> to break the bungee AND the factory specified safety cable is quite
> likely to over stress the anchor point. Ergo, it is probably not a
> good idea to add strength to either, and in particular to strengthen
> the safety cable. The energy dissipated by breaking the bungee might
> protect the anchor points from damage but I suppose that breaking the
> cable will definitely cause some damage and breaking a thicker cable
> would cause even more damage. Any landing bad enough to break either
> is likely to be expensive so I guess I'm just quibbling about what
> pieces will need to be repaired.
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