Originally Posted by
Airbubba
Actually the CAB accident report said that the negative acceleration increased to a mean value of about - 2.8 g so the peak before the aircraft broke up may have been even higher.
Originally Posted by
Sailvi767
Their indicated airspeed to reach those negative G values were in excess of 400 knots. Not possible to get anywhere near those numbers at 210 to 230 knots.
Originally Posted by
henra
In the trace of the 720 accident you can see that at 220kts it produced ~ -2g, increasing to -2.8g @ ~280kts.
One of you may be right, I'm not so sure that wing loading at max gross weight is what determines the negative g capability of an airliner. The -4 g claim may indeed be from a typo in a forum posting.
It looks to me like the Atlas 767 must have been very light to climb to FL400 immediately over the Gulf of Mexico.
Freighters continue to crash at a significantly higher rate than passenger planes at U.S. carriers as we have often observed here over the years.
There are a lot of B-763's still flying, I would think that if there was an early indication of a mechanical failure in this Atlas mishap, the NTSB would say something by now.