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Before the collision at Tenerife the pilot of KLM Flight 4805 caused a 22-meter (72-foot) tail-strike by rotating early (I can't say that I blame him given the circumstances).

Is dragging the tail on the runway the best course of action in scenarios where a liftoff must happen as soon as possible?

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    $\begingroup$ I'd speculate that it wouldn't have helped. He actually managed to get airborne before takeoff speed by creating a high angle of attack. He just didn't get it high enough. I don't recall anyone saying they stalled before impact, so if he had kept the AoA down below tail strike angle he wouldn't have gotten airborne at all $\endgroup$
    – TomMcW
    Feb 13, 2017 at 22:21

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Near as I know there are no emergency takeoff procedures and for good reason: if you do have an emergency, stay on the ground. Period. As for emergencies which happen during a takeoff roll, this one really isn't covered among them as there really is no emergency regiment to get airborne. The KLM captain in the Tenerife accident made a series of judgement errors and failure to follow ATC instructions combined with bad weather and a crowded airport which contributed to the accident. Once he was rolling, the best he could do was just hope the plane would reach Vr and climb over the PanAm jet, which didn't happen. He panicked at the end with the tail strike, only making things worse. But at that point he had painted himself into a corner with no escape.

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  • $\begingroup$ Great and if you can attain that speed, so be it. This guy could not. $\endgroup$ Feb 13, 2017 at 23:05
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    $\begingroup$ @ymb1, VMU is measured by tail dragging (equipped with an auxiliary wheel for the purpose). But rotation adds drag and tail strike adds a lot more, so in normal operation, earliest lift-off would be achieved by waiting for VMU and then pulling to just below the tail-strike attitude. And if you also need to climb out, you actually need to wait a bit longer before rotating, because at VMU the wheels will leave the ground, but the plane won't climb out of ground effect. $\endgroup$
    – Jan Hudec
    Feb 14, 2017 at 8:15
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    $\begingroup$ I realize that I'm playing Monday morning quarterback but in theory he could have possibly had a better outcome by gaining as much speed as possible with wheels on the runway and then pulling up just short of a ground strike at the very last moment. Does that sound right? $\endgroup$ Feb 14, 2017 at 23:04
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    $\begingroup$ Yeah. He could have been not so impatient to go that he ignored the PanAm 747's radio call that it had not cleared the runway during its backtaxi, adding another 40,000 lbs of jet fuel prior to departure, and worked better with his FO. That probably would have prevented the accident from happening in first place! $\endgroup$ Feb 14, 2017 at 23:12
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    $\begingroup$ Just a small point, he didn't ignore the PanAm call, he didn't hear it as there was another call at the same time. $\endgroup$
    – Ben
    Feb 15, 2017 at 2:38
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The best way is to build speed as soon as possible. Tricycle gear are helpful as they keep the wing at a low angle of attack prior to rotation. Unless the field is soft or muddy, this would be the way to get airborne, perhaps with a bit of flap just before rotation.

Another very valuable technique is the rolling start from the taxiway, which carries a few more precious knots into the takeoff run.

Bottom line is one needs speed to fly. High AOA tailscraping is not the best way for a given amount of thrust and weight.

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