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Everyone knows that doing a go-around is a normal procedure, although the go-around happens usually before applying the brakes system (spoilers, ground/air brakes, and/or thrust reversers), but, could you perform an aborted landing after using any brakes system?

Of course, this is not for a normal flight/landing, and there must be some conditions, like enough runway to gain speed again, and of course you should be not so low from Vr speed.

Let's see why someone could do an aborted landing after braking: There were at least two cases (Atlantic Airways Flight 670 and TAM Flight 3054) where the braking system just "fails" (actually both were a pilot's error, but let's say that was just a mechanical error).

Of course you will only notice that the braking system is failing when you activate it, and maybe is not like they are not working at all, but just working poorly, so you could see that the speed is slowing down, but also you can see that is not normal and maybe you just need to takeoff again and do another approach, or even going to another airport for a longer runway so you could safety brake with your malfunctional braking system.

After that explanation, I have two questions:

  1. Can you technically perform an aborted landing after braking? I mean, could the automated braking system or the flaps settings interfere?
  2. Would be this procedure be in any airline/airplane manual in case of a malfunctional braking system while landing? (i.e., an official procedure for this type of case)
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    $\begingroup$ Welcome to Av.SE! $\endgroup$ – Ralph J Jun 12 at 1:16
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    $\begingroup$ TOGA is an engine/thrust setting or switch ( en.wikipedia.org/wiki/Takeoff/Go-around_switch ) an aircraft cannot perform one. $\endgroup$ – Federico Jun 12 at 9:59
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    $\begingroup$ Whether an airplane can take off again after landing is dependent on runway length, given enough runway an airplane could come to a complete stop and take off again. $\endgroup$ – GdD Jun 12 at 14:09
  • $\begingroup$ @Federico my "TOGA" is actually just a term that I invented for this question. I know that the real "TOGA" is a button/switch often located behind or below the throttle handhold. I will edit my question to make it clear for new visitors anyway. $\endgroup$ – JuanP. Zuniga Jun 12 at 14:51
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    $\begingroup$ @JuanP.Zuniga aviation is an established industry. re-using terms for made-up meanings brings confusion and does not help the conversation $\endgroup$ – Federico Jun 13 at 5:43
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Disclaimer: I'm not an airline pilot so don't just take my word and apply it in a real world environment

From my understanding:

TOGA means takeoff/go around and is usually a thrust setting of the engine. It can also be the vertical or lateral mode of an autopilot/flight director. I haven't seen anyone referring TOGA as a situation of flight though. "I've flown a TOGA" is a thing that I have never heard.

Touch-and-Go: Performing a landing and aborting it after you have touched down. Usually this is planned ahead of time and ATC issues a "cleared touch and go" or "cleared for the option" instead of "cleared to land". Usually ATC doesn't expect a message from you during the go-around phase as far as I know.

Go-Around: Aborting a landing in general. My understanding of a go-around is aborting an approach before touching down. ATC usually expects a "going around" message from you.

Aborted landing: Similar to go around but my understanding would be that it takes place after you have touched down. The reasons may be a bounced landing, a late touch down with too little runway remaining or things of that nature. They are unplanned in comparison to a planned touch-and-go. ATC probably expects a "going around" from you.

Stop and go: Performing a full stop landing and taking off right after. Should be requested from ATC and depending on traffic it may not be possible. It gives you time to go through all checklists before taking off again and does not require a long taxi back. Usually this is only done by general aviation aircraft when the runway is long enough.


Now to the "Can You Do It?" question:

With a long enough runway you can easily perform a full stop landing followed by a normal takeoff ("stop and go") or a "touch and go". The worst case is an engine failure at V1 during the 'go'-phase. You'd have to guarantee that the aircraft will be able to stop on the remaining runway or that you are above minimum control speed in order to stay on the runway and climb out with one engine inoperative. This is probably the reason why it's usually not considered as a safe option to go around after you have already slowed down significantly.

There are many other factors that have to be taken into account though:

  • Operating manual may prohibit it.
  • Company rules and guidelines may prohibit this even if may be physically possible and safe to do so.

Actions that will have to be performed during the touch and go:

  • Ground spoilers should retract as you move thrust levers forward. You have to verify that this happens.
  • Autobrakes will disable almost instantly once you move the thrust levers forward. You have to monitor that.
  • The feet of the other pilot in the flight deck have to be off the brake pedals. In an emergency situation it could happen that the rules of "pilot flying" and PNF are not respected by the other crew member and that they think the autobrake may have failed and they try to stop the plane. Communication needs to be clear.
  • Pitch trim has to be reset for takeoff. You have to do that manually in most aircraft
  • Engines have to be stabilized for a brief moment before adding full thrust if you are slower than minimum control speed.
  • Time between commanding full thrust and actual engine thrust can be 5 seconds or longer.
  • If you applied reverse thrust and switch directly to forward thrust you will need to make sure that both reversers are stored and properly latched closed before you can apply lots of forward thrust. The last thing you want is both engines on max thrust with one reverser still open.
  • Brake temperature. If you have already decelerated significantly then your brakes will be quite hot but the indicated temperature usually lags behind. Max indicated temperature is usually reached several minutes after landing... So you don't actually know how hot your brakes are until minutes later. Before taking off again you should verify that brake temperature is not too high and within limits for a potential rejected takeoff. If you decelerated only a little bit and noticed that braking action is poor then there is no physical reason as to why the brakes should be too hot.
  • Flaps will need to be raised from full landing configuration to go around position. It may take several seconds before the flaps reach that position. During this period you have a lot more drag which reduces the acceleration.

During all this time you have you're just wasting runway length. If you're going 130 kts for just 5 seconds this means you waste roughly 330 meters or 1100 feet before you start accelerating again.

  • Due to the retraction of the flaps you reduce drag but you also lose lift. I see no physical problem doing that while you are on the ground rolling but if you are already airborne again you may need to wait for a good positive rate and good terrain clearance before you can attempt that.
  • Climb performance with flaps extended may be significantly worse - so terrain and obstacle clearance have to be checked.

Usually there won't be time to check the proper pitch trim setting, check the proper V1, VR and V2 speeds during such an event. And if you have enough runway left to do all that you may as well stay on the brakes and add full reverse thrust to stop.

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    $\begingroup$ Thanks a lot jan. I'm not even a real pilot (although I want to learn to fly at least in general aviation) but I can tell that this is so logical, even me who love logical thoughts, I wouldn't think about those steps to follow just to take off again just right after landing and braking. Of course I knew that every second that you use, you are taking a lot of vital meters/feets from the runway, but I didn't know that it could be a lot of time for take off again. $\endgroup$ – JuanP. Zuniga Jun 12 at 14:40
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    $\begingroup$ ATC does expect an "Acme 1234 going around" call so they can move other traffic where it needs to go, but only once it's safe. It's usually pretty clear what's going on, and even a decent tower will be working out who needs to move where before the call is made, but it still should happen. "Going around" is a declaration, not a permission request. ATC has no say in the matter as safety is entirely the cockpit crew's responsibility. Small planes often call it out after they've already left the ground, and they have much less to do. Airline crews have a much longer list of steps to complete. $\endgroup$ – NetworkLlama Jun 12 at 15:55
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Immediately after touchdown, the autobrakes will start to function, and may start applying the brakes depending on the aircraft's deceleration and the commanded deceleration. If the pilot hasn't yet started to deploy the thrust reversers, a go-around is still possible at this point. Advancing the throttles will disengage the autobrakes, and it's a normal balked landing from that point.

Also, advancing the throttles will stow the speedbrakes as well -- this is the way the system is designed, for exactly this sort of a condition.

As discussed elsewhere, once the thrust reversers are deployed, you are committed to stopping; a go-around is no longer safe to attempt after that.

If the brakes malfunctioned in a manner that the crew only became aware of after landing, chances are that they'd only become aware of it well after the thrust reversers were deployed, so the go-around isn't going to happen in response to that. Thankfully, the wheel brakes on modern airliners are extremely reliable, and I can't think of any example of this sort of a failure. If it did happen, you'd stay in max reverse as long as possible, use the EMAS if the runway has it, and use any available braking that you have (i.e. if the brakes on one wheel had failed but the others hadn't). But it's not something that tends to happen on modern jets.

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    $\begingroup$ I didn't know that there was a significally delay when you rectract the Reversers or even failing to. I tried searching this question before asking it here but I didn't get that type of answer in my search. Thanks for sharing! $\endgroup$ – JuanP. Zuniga Jun 12 at 14:31
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    $\begingroup$ I'm not a pilot, but my understanding is thrust reversers are most effective at high speeds (right after touchdown) so if the brakes weren't working properly without a warning, the jet would still decelerate quite a bit; say, from ~150 knots or whatever touchdown was to like 90 knots before the reversers began losing effectiveness and the poor braking action became more noticeable. Again, not a pilot. $\endgroup$ – CodeShane Jun 13 at 8:00
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    $\begingroup$ @CodeShane Your understanding is exactly correct. In the case of a short runway where I do apply the wheel brakes firmly enough right after touchdown that I'd expect to feel significant added deceleration (i.e. so I'd have an early cue that they aren't working), that's the case where I want the reverse thrust promptly as well, so again, the TR's are deployed by the time I'd know of a brake problem - even if it were to be at the higher speed. But normally, wheel braking isn't perceptible until ~ 80-100 knots, for exactly the reasons you explained. $\endgroup$ – Ralph J Jun 13 at 13:37

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