I've seen videos on youtube where the pilots always turn on engines 4 and 3 (in a B747-4) first and then turn 2 and 1 on after pushback. Is there a reason behind this, and does the same reason apply to all multi-engine aircraft?

  • $\begingroup$ There's a lively debate about this, pprune.org/tech-log/415625-747-2-engine-start.html. The consensus seems to be that starting one at a time is nicer to the APU, and starting some before pushback ends saves you precious seconds at a busy airport. $\endgroup$ Oct 13, 2020 at 3:13
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    $\begingroup$ Welcome to aviation.SE! Does this question help? This one and this one might also be relevant. $\endgroup$
    – Pondlife
    Oct 13, 2020 at 4:19
  • $\begingroup$ Short answer is it depends on the airplane. $\endgroup$
    – GdD
    Oct 13, 2020 at 7:13


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