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Old 5th March 2012 | 19:13
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john_tullamarine
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why would we limit V1 in order to be able to stop with some distance remaining?

perhaps we might prefer that to stopping with some grass behind us ?

Putting aside facile comments, the problem comes down to one of risk and risk management for managing an engine failure.

By far the greatest risk during takeoff is a critical accel-stop manoeuvre. The margins (especially pre-amendment 42) are such that one should prefer other alternatives.

The continued takeoff, on the other hand, offers far lower risk, especially as the aircraft progresses away from the runway and the gross-nett delta provides an increasing terrain clearance pad.

Caveats -

(a) for very lightweight takeoffs operating to min speed schedules, the proximity to the real world Vmcg may make a continued takeoff very difficult

(b) in the real world, the range of failures and problems which might warrant rejection aren't necessarily embodied in the AFM certification data.
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