Matt Whiting wrote:

I'm not as certain as you. Ground effect begins to be detectable at one
wing span of altitude above the grond, but just barely (see reference).
I was always taught that it really is only signficant at 1/2 the wing
span. However, I agree with you that the airplane appeared to get 50 -
75 feet high which is well out of ground effect. He should have been
able to fly away once getting to that height. I wonder if something got
into the controls or something like that. I just am not sure that what
we saw is completely explained by either overloading or out of balance.

Matt

Sorry, forgot the reference.

http://avstop.com/AC/FlightTraingHan...undEffect.html

Matt