With all of this discussion on max gross weights for the Lancair 320/360,
what is the engineering/design decisions that has gone into increasing the
gross weight? The reason I ask is that, I assume, the factory has done some
type of engineering analysis. The factory increase in gross weight document
is:
ncrease320-360.pdf
Here, it states that the new main gear overcenter link must be used
(Standard in kits produced after 10/93), the stall speed will be increased,
and the allowable G limits are reduced to +4.0/-2.0. (Those reduced G limits
aren't normally a problem for me) The maximum landing weight has not been
changed.
In Mac McClellan's blog
asserts that all changes to a kit make each one a one-off. He refers to
Dick (Van's) VanGrunsven's article about the engineering that goes into
setting the RV-10's gross weight:
While Van (nor I) dispute that there are airplanes flying around
(successfully) with higher gross weights, I'm concerned that I do not have
the engineering background to justify any gross weight other than to use
what the factory provides. Vans asserts that the built-in engineering
margin belongs to the designer and you can't have it.
In particular, does the G loading become so low that I'd have to be
concerned about turbulence breaking my wings off? I have no idea.
Granted, the 360 has a lot of factory options. And I agree that no two are
probably alike. But I feel a little better while building mine that I'm
sticking to something that a real aeronautical engineer designed and
approved. (That is meant that *I* do not have the aeronautical engineering
skills to make that determination, I can't speak for anyone else)
Thoughts?
I have no idea what mine will weigh when finished. But I know the
girlfriend likes to pack heavy. Might be time to look for a 4-place...
-Rob (Lancair 360 MKII, 15% completed)
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