Need Help on Landing Gear Calculations
"Dick" wrote
I'd rather not drop my plane with engine G but am looking for a way to just
test the gear assembly. Was thinking ; restrain the top connection of the
gear leg and apply a uplifting force on wheel via some sort of lever setup.
The drop test points out possible shortcomings in the landing gear, but also
weaknesses in other critical areas.
An engine being dropped and suddenly stopping when the landing gear stops the
plane, will put a lot of force on the engine mount and firewall. The wing spar
will experience a very high load, if the gear is wing mounted.
The aft fuselage will try to bend downward, as the front of the fuselage is also
bending downward, so will the fuselage experience too much tension on the top,
and too much compression on the bottom?
I would propose putting the landing gear on separate roller platforms, so it can
experience whatever splaying may result when the gear is highly loaded. Then
load the areas with sandbags at the multiple of G's for whatever that part or
system weighs.
For example, if the drop test is expected to put a 10 G load on the plane, and
the engine weighs 200 pounds, you need to stack 2,000 pounds on and around the
center of gravity of the engine. Do the same thing for every area of the plane,
such as on each wing, and area of the fuselage, and don't forget, that much
weight needs to go in the driver's seats, too. g
Wow! Typing that out, it is suddenly very clear why people do drop tests,
instead of static tests.
--
Jim in NC
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