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< We are all aware of how strong the wings are on the Lancairs capable of
withstanding +9 g's but it won't do you much good if you lost your engine
passing through 4.4g's. <

Let's be careful that we don't confuse design limit load with the ultimate
load.  When a composite wing breaks, it snaps.  When an aluminum wing
breaks it usually bends.  I once had a student that though it would be a
good idea to try and loop a C-150 without training.  He exceeded the
ultimate load and bent the wings but made it home OK.  He would not have
been so lucky if he had exceeded the ultimate wing loading in a composite
winged aircraft.  The point is that the design margins for composite wings
need to be larger than AL wing structures thus the 9 "G" ultimate mentioned
above .

The design limit load is the maximum actual loading the aircraft will
experience in flight.  Is the 4.4 "G" engine mount a design limit or an
ultimate?  If it is a design limit with a 150% margin the ultimate limit is
6.6 "G".  I begin to pass out at 4 "G".

Jim Frantz

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