Originally Posted by
atakacs
Not sure to follow you train of thought. Do you mean that if the aircraft was 1.5t lighter it would have accelerated faster, thus not hitting the titanium strip ?
My assumption (Knowing assumptions are dangerous) is that the crew did one of two things, or perhaps both.
1) The aircraft was overweight. This caused a number of speed related problems.
They did not recalculate takeoff speeds. According to various interviews and info regarding the accident, the captain took on something like 1 ton of extra fuel in addition to the extra baggage. They had planned for extended taxi time either due to traffic or for positioning on a different runway.
However, they did not end up burning that fuel before attempting the takeoff. The assumption is that they tried to take off at speeds calculated for a lower fuel AND baggage load.
2) The aircraft took off with a tailwind without recalculating the v-speeds AND without factoring in the tailwind component as it would affect the aircraft at the higher takeoff weight.
So one can surmise that they not only had some kind of gear problem during the takeoff roll that may have prevented them from accelerating at the normal speed, and they may have had steering difficulty while on the roll, but they also rotated far too soon due to not recalculating, maybe as much as 10 knots under the correct speed, plus the fact that they were overweight, with a tailwind not helping things, and then the engines were shut down, all while being on fire and with possible damage or debris causing drag all over one side of the aircraft.
The extra tailwind component could have been the difference between staying up and going down. They must have been below their engine out safety speed. Had they calculated correctly, the aircraft -may- have been salvageable if the fire did not consume the aircraft in the air. Had they lifted off with 5-10 knots more speed as would have been proper, they would have made their engine out speed and thus could have flown out of the death-drag curve, in theory.
In a delta wing aircraft excessively early rotation with insufficient thrust to lower the AoA results in something called aerobraking. Among other things it's used to slow down spacecraft reentering the atmosphere. It is remarkably effective at slowing down airplanes. On the runway it kills acceleration, in the air it turns you into a flying brick.
I feel bad for them but there were a lot of amateur mistakes made in allowing the aircraft to even take off in that condition. There are a million youtube videos of aircraft ranging from cessna to airbus showing the disastrous or near disastrous results of trying to take off while overweight and in bad conditions i.e. density altitude stuff. Tail strikes being the best case scenario, crashing into trees or water at the end of the runway being the more common scenario.
These guys didn't have a chance past V1 IMO. Too many bad choices.