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I just read an article about a day in the life of a pilot and it states "The Captain always controls the thrust in the unlikely event that the take-off needs to be aborted for safety reasons." Is this correct?

It was always my understanding that the roles of PF and PNF can be alternated between the captain and first officer, and controlling the thrust would fall into one role or the other. I also recall seeing videos of the flight engineer pushing the throttles.

If the take-off needs to be aborted, can't the captain just command the FO to "abort" or take control by saying "I have control" or similar?

Finally, will pulling back the throttles be enough to abort takeoff safely without braking? Surely it would just cause more problems?

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    $\begingroup$ I recently saw an old Concord video where the FE handled some of the thrust settings. $\endgroup$ – hiergiltdiestfu Mar 27 '17 at 15:20
  • $\begingroup$ I've seen the same for the B-29. Engineer handling engine thrust. $\endgroup$ – AaronLS Mar 28 '17 at 15:36
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I believe your referenced material is mixing up "Captain" with "Pilot Flying". The person in control of the aircraft should have their hands on the throttle, Captain or not.

If the take-off needs to be aborted, can't the captain just command the FO to "abort" or take control by saying "I have control" or similar?

Having your hands on the throttles has a number of advantages:

  • You don't have to waste seconds (which at 200mph means about 300 feet per second)
  • You don't have any confusion (i.e. "What did you say?")
  • You don't need to discuss it with the other person (you say abort, FO says OK)

A lot of companies require both the PF and PNF's hands to be on the throttle at the same time, which has the advantages of 1) assuring that the throttle is set to its maximum power, and 2) either one can abort without having to command the other to do it. Either pilot (or the FE if they exist) have the ability to call an abort before V1, and the entire cockpit crew should follow that course without discussion until clear.

I also recall seeing videos of the flight engineer pushing the throttles.

There are also cases where if a FE is required (which usually is not the case anymore), that the FE also has their hands on the throttles along with the pilot/copilot.

Finally, will pulling back the throttles be enough to abort takeoff safely without braking? Surely it would just cause more problems?

Depending on how fast you are going, it is almost always the case that you will have to brake as well. Airplanes are pretty slick at rolling down the runway and relying on drag alone to stop you will probably result in an overrun. Usually the PF will be the one on the brakes, but the PNF may also be applying pressure just in case.

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    $\begingroup$ Good answer! In modern aircraft it's usual to set the autobrake system to MAX (Airbus) or RTO (Boeing) and the Spoilers into the armed position (at least for Airbus, not sure about Boeing). If set up the aircraft will brake with maximum brake power available and extend the spoilers to ensure maximum braking effieciency. $\endgroup$ – pcfreakxx Mar 27 '17 at 14:20
  • $\begingroup$ @pcfreakxx Good point, I forget about the auto-brake systems. $\endgroup$ – Ron Beyer Mar 27 '17 at 14:23
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    $\begingroup$ assuring that the throttle is set to its maximum power I thought I read in some other post somewhere on this site that maximum power is generally not used on takeoff for economic/maintenance reasons. Is that not the case? $\endgroup$ – David says Reinstate Monica Mar 27 '17 at 16:10
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    $\begingroup$ @DavidGrinberg Depends on the airplane. In airliners, you're right that it's not normally actually maximum power, but rather a detent for "takeoff power" and what that actually means has been set up in the flight computers ahead of time for this specific takeoff (as it can vary based on temperature, humidity, runway length, aircraft weight, etc.) However, for light aircraft, it's normal to use full power on takeoff. $\endgroup$ – reirab Mar 27 '17 at 17:58
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    $\begingroup$ @DavidGrinberg reirab is correct in the above comment. Some airliners have a "Take-Off-Go-Around" button/detent which uses the calculated take-off power at the Take Off detent on the throttles. The "Go around" detent is different performs different things regarding power and autopilot. $\endgroup$ – Ron Beyer Mar 27 '17 at 18:21
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As an addition to Ron's otherwise good answer, since I feel one aspect was left out.

Some airlines (ie. the one I work for) require the commander be in control of the thrust levers until V1 (take-off decision speed). That is because the decision to stop the take-off roll is not a light one, and the captain is the one to make the decision. And as Ron pointed out, there is no time to move hands when needed.

The control flow goes as follows (consider F/O as PF)

  • F/O has control of aircraft, announces "take-off"

  • F/O advances the levers to T/O thrust, then lets go of the thrust levers

  • CDR places his hand on the thrust levers

  • Airplane accelerates and passes V1, the CDR lets go of the thrust levers

  • Once airborne, the F/O takes control of the thrust levers again

  • If the take-off needs to be rejected, the CDR takes control of the aircraft and brings it to a stop using (auto)brakes and reverse thrust while maintaining the aircraft on runway centerline. F/O monitors and informs ATC

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Regardless of who is Pilot Flying, the commander will take control of the thrust levers once the thrust is set. A First Officer acting as Pilot Flying will resume control of the thrust once the commander has removed their hand from the thrust levers at V1 AND the aircraft is airborne.

The decision to reject lies solely with the commander. As such, once the thrust is set, the First Officer as PF will have no further need to touch the thrust levers until the thrust reduction altitude. Hence the commander will cover the thrust levers in anticipation of rejecting the takeoff.

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