My tweet entitled “Determining Piloting Factor in Air Crashes and Miracle Landings” received a certain amount of interest and I am looking into the concept more deeply.
Now I think “Clincher” sums it up better.
While an accident or the avoidance of one is usually the result of a whole series of factors, both technical and human, a single factor or combination of factors at the end (or taken overall) is the clincher–something that makes all the difference. This is not necessarily related to responsibility. It can be just a matter of luck or bad luck.
I cited the case of the Air France Flight AF447 that dropped like a brick into the South Atlantic after the most junior of the copilots left in the cockpit put the aircraft into a steep climb and stalled it. There were many contributory reasons for the disaster but the clincher in my opinion was that he did not believe the aircraft could be stalling (despite some fifty warnings) because they had set the thrust for TOGA (take off go-around) which at ground level would pull them out of one. At high altitude all TOGA did was to push the nose up and stop the aircraft diving, gaining speed and recovering.
Miracle on the Hudson
The clincher in the Miracle on the Hudson was the coupling of Sully’s successfully ditching the aircraft without it breaking up with the presence of the calm river and rescue craft able to reach them within three minutes, not forgetting that (unusually for a domestic flight) the aircraft had life rafts.
For Qantas QF32, where an engine of an Airbus A380 disintegrated after taking off from Singapore with shrapnel impairing some 95% of the systems, the clincher was the superlative teamwork over the hour and a half prior to landing coupled with the deft landing of the greatly overweight super jumbo at just the right spot.
Had the landing been too hard or delayed, the undercarriage could have collapsed either on touchdown or on the grass beyond the runway. In either case fire would very likely have broken out.
Worst-ever Multi-aircraft disaster (Tenerife)
In the worst multi-aircraft accident ever, the collision of two 747s in fog on the runway at Tenerife, the clincher was the rush to take off coupled with simultaneous radio transmissions making one warning of the other aircraft being still on the runway being unintelligible. (A clincher preventing the disaster could have been the the flight engineer being forceful in saying the other 747 was very possibly still on the runway, though admittedly his position was difficult.)
Our book starts with the disappearance of Amelia Earhart on her attempt to circumnavigate the world in 1937. The clincher there was her failure to ensure she could receive (and determine the direction) of radio transmissions from the Coast Guard cutter Itasca waiting beside minuscule Howland Island on which she was supposed to land.
Not every crash or miracle landing has a clincher but it is something worth trying to identify, even though the essential cause and responsibility often lie elsewhere. It can lead to a better understanding of the event.