Quote:
Here in Canada we can declare whatever gross weight we want (wisely or
not). Seeing that the added weight is itself in the wing and results in no
increased stresses, I figure I could simply increase the gross with long
wings by the same 100lbs without penalty (assuming enough HP). No?
It is true that inertia relief can be credited to mitigate loads and this gives
a proportional benefit with heavy wings. But to assume the stresses do not
change
is incorrect. The MG wings generate more lift, hence the bending moments
and shear forces on the root will be higher.
I believe the spar depth was changed to increase 2nd Mt of area. The goal
therefore
may have been to match the standard a/c stresses. I have some of Jason Russell's
work on file from many years ago, it is probably worth taking a look at
that and any other design data (at LAA?) to see what the margins are.
I suspect that the long delay in gaining approval for the MG version stems from
a reduction in structural margins. Perhaps someone can tell the story????
--------
John Wighton
Europa XS trigear G-IPOD
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