"Ron Wanttaja" wrote

I pegged a 4-G g-meter on a landing once. No damage, and that was on a gear
leg
that had been improperly repaired from a crash 15 years earlier.

Thanks, Ron, for a partial confirmation of my concept.

See if you 'all can follow my reasoning, here.

A plane is commonly certified for -3 G's. That means all of the weight of the
plane is supported by the wing. Good engineering would place ultimate failure
at at least 1.5 times the 3 G's. That means the wing would hold 4.5 G's.

That means the wing was holding all of the weight of the plane. What would the
wing weigh, compared to the whole plane? Perhaps 1/4th of the weight?

If the wing were to fail from a landing, overflexing the wing, it would take a
landing of 4 times the 4.5 G's, or 18 G's.

Now, I give that it is unlikely to fail a wing from a hard landing, but people
do fail wings from crashes. (that is a landing, right? g) Wayne Hadley thinks
his crash was about 27 G's One has to think the gear absorbed at least 1/2 of
the force, right? So it follows that I would want my gear to stand up to at
least 10'G's before it folded flat, or ripped loose from the fuselage or wing.

So, if my gear were to stand up to drop test at 10 G's, and it had a 12" travel,
how high would the plane have to be dropped from, to achieve that force?
--
Jim in NC