Originally Posted by Clandestino
There is no dissenting opinion included in the NTSB report. NTSB is pretty clear that too low power did not cause the accident on its own but that without it, the catastrophe would not have happened
With my respectful apologies to
sabenaboy after having agreeing to take his very appropriate and very worthwhile recommendation … I feel one last rebuttal may be in order.
Of course there is no “dissenting opinions included IN the NTSB report … that’s not what NTSB reports do … but that doesn’t mean that there are NOT a large number of aviation professionals who have dissenting opinions about what that report says. As the investigation revealed (and referenced here) the “low power setting” of the engines did not cause the accident” … but the only way an airplane could have continued flight – even with all the power both engines were capable of producing - would have been if the attitude of the airplane was such that the engines – even at Max Thrust – could have pushed the airplane through the air at the attitude achieved at that time. Recall the video of the F-100, with the afterburner lit? Recall it wallowing through the air prior to impact? … this was THE specific event that generated the term “Sabre-dance.” That F-100 SuperSabre was at a pitch attitude that even with the A/B blasting everything under it into small dust particles – there was insufficient thrust to push that airplane in the direction opposite to that thrust. So too was that B-737 … the pitch attitude of that B-737 – caused by the uncontrolled pitch-up caused by the incorrect deicing/anti-icing procedures applied – was such that all the thrust of both those engines – and I don’t care what power setting they could have selected – would have resulted in exactly the same end … just like what occurred to that F-100 SuperSabre. Just in case you forgot, jet engines produce thrust to push the airplane in the direction opposite to that thrust vector – nothing more – nothing less. With any thrust, an airplane would be able to be pushed only in the direction
opposite to that thrust direction. In both of these cases, the F-100 and the B-737 … there wasn’t enough thrust capable of being generated even with the added thrust of the A/B in the F-100 case … even with full power, maximum power, throttles-bent-over-the-fire-wall power in the B-737 case – there wasn’t enough thrust to push the airplane “forward” sufficiently to achieve sufficient lift to maintain flight. And, before someone points out that "they did it in a simulator." Yeah. I know something about simulators as well ... and given the right knowledge and time at the simulator's input keyboard, I can make a Cessna 152 simulator "fly" just exactly like the space shuttle.
Originally Posted by M.Mouse
So how do you answer AirRabbit's conjecture that the B737 characteristic for alarming and uncontrollable behaviour with leading edge contamination possibly occurred and all that greater thrust would have achieved would have been that the aircraft and its occupants would have reached the point where the tragedy was inevitable marginally quicker?
Addressing that one point would be appreciated, my apologies if I have missed where you have addressed it.
This is probably the “question of the thread,” thanks, M.Mouse!
As I pointed out … way back on April 17th in post #276 …
I believe that once this crew pushed the throttles forward with the intent to takeoff, they were doomed. The only way that an accident could have been avoided at that point, was to have kept the airplane on the ground until a sufficiently higher airspeed was reached prior to initiating the rotation. Unfortunately, not only did the crew not know that this would be necessary, they wouldn’t have known the “magic” airspeed number. Even if they had pushed both throttles all the way to the firewall from brake release, and then rotated at the computed rotation airspeed (as they did) the airplane would have performed in exactly the same way. It would have uncontrollably pitched up to at least the 22 – 24 degree attitude; likely more given witness statements … where some said they saw “the aircraft was flying at an unusually low altitude with the wings level at a nose-high attitude of 30 degrees to 40 degrees before it hit the bridge.” It would have entered the same deep aerodynamic stall. The flight crew would have been unable to bring the nose down aerodynamically. Unfortunately, in that condition, full thrust on both engines would have been insufficient to maintain flight. All who were affected by this tragedy were victims of longitudinal differential lift. The flight crew did not have the luxury of time to analyze, consider, and choose accordingly.
Had this B-737 flight crew kept the airplane on the ground until achieving a forward speed sufficiently high to have produced lift even somewhat evenly along the entire length of both wings – the asymmetrical longitudinal lift components may have been small enough that the pilots could have maintained control. However, when the F/O brought the control column back to a neutral position – in anticipation of rotating at the computed "rotation" speed (however he was planning to rotate – to whatever attitude he planned to rotate) – the airplane took over … snatching the pitch control completely away from that pilot and taking that airplane up to an attitude that achieved a rather severe stall buffet only 3 seconds after having all three gear (the nose and both mains) on the runway. THAT was the reason the Captain was recorded as saying - at THAT specific time ... "Easy!" Conservative estimates say that the stall buffet wouldn’t have been reached until the pitch of the airplane achieved something like 24 degrees – so, the pitch attitude was at least that high. Some witnesses (forming angles with their hands when specific numbers made no sense to them) indicated to investigators that the airplane may have been at an attitude of more than 40 degrees nose up. Think about that for a minute … 40 degrees nose up! With the airplane's forward momentum (which is what got it from the runway to the 14th Street bridge - it certainly didn't "fly" there) it’s almost anyone’s guess as to what Angle of Attack was actually achieved. So ... was it possible for that crew to make that B-737 "fly" at that pitch attitude ... with that AoA ... with a measley additional 15-20% thrust? Not at that kind of airplane attitude – talk about “son-of-Sabre” … as I said previously, an Atlas Booster would have had problems getting that airplane to "fly."
For Reference:
Aviation Video: F-100 test flight crash (Sabre Dance) | Patrick's Aviation