Mis-loaded B747 freighters
tdracer #29 and DaveReidUK #30.
I agree I have overstated the problem, after reading through the ASN Aviation Safety Database for the 747.
As it happens the two hull-losses that I had in mind are not straight-forward arguments for self-weighing: MK 1602 at Halifax 14 Oct 04 and Cargo B 3101 at Brussels 27 Oct 08. In both cases the physical loading was not in question; the data were mis-loaded by the flight crew. In those situations probably neither flight crew was enough on the ball to make prudent use of any cautionary information from the undercarriage.
Indeed, the Cargo B crew belatedly corrected their load figures, so an undercarriage cross check would only have comforted them; their disastrous mistake was not to recalculate the take-off speeds to fit the 100 tonnes extra weight they had stumbled upon.
As to the Bagram loss, I would insist that “improperly restrained cargo” is “badly loaded”, but that has nothing to do with self-weighing. Still, of the three cases, this was one where the captain could have felt “if they get that wrong, what else are they going to get wrong ?” To my mind the critical failure – and unbearably sad to tell – was that the aircraft loadmaster, on the ground at Bagram, seems to have seen that the restraints fitted at Camp Bastion were failing but could not bring himself to get them fixed before his aircraft again took off.
If I was to persist with my case, I could look into all the crashes of old airliners of other makes or models for evidence that they were misloaded freighters. I do not think I will bother.