In general, a go-around, in a jetliner, must either be performed before thrust reverser deployment, or not at all.

  • This is because attempting a go-around after reverser deployment may result in loss of control of the aircraft.
  • Loss of control is a possibility because one or more of the reversers could fail to stow during the attempted go-around, potentially resulting in an asymmetric-thrust situation beyond what most jetliners are designed to handle.
  • This is because the reversers take several seconds to fully stow once deployed, and the aircraft could easily lift off before this happens, in which case any not-yet-stowed reverser buckets or clamdoors will be blown back to their fully-deployed positions by the aerodynamic forces on said piece(s) of reverser hardware.
  • Lifting off is relevant because, when the aircraft lifts off, the reverser actuators are automatically locked out and depressurised.1
  • The reversers are locked out when airborne to minimise the risk of an uncommanded in-flight reverser deployment, which, for aircraft not certified for in-flight thrust reversal, is generally bad.

However, some aircraft are capable of, and certified for, the safe use of reverse thrust in flight (typically to steepen descents by using reverse thrust as an airbrake [DC-8, Trident, Concorde, C-5, C-17], or to shorten the landing roll by deploying the reversers while still airborne rather than having to wait until after touchdown [Trident 1C, Il-62, Tu-154]).

  • To allow this inflight use of reverse thrust, the reversers on these aircraft are not locked out when airborne.
  • As such, the reverser actuators remain pressurised even after the aircraft lifts off.
  • Consequently, even if the aircraft lifted off before all reversers had fully stowed, the reversers would simply continue to stow.
  • As a result, lifting off with one or more reversers still in transit would not produce a significant risk of a severe asymmetric-thrust situation.
  • Even if, for some reason, a reverser did fail to stow, resulting in thrust asymmetry, aircraft certified for inflight reversing are required to remain controllable even with full forward thrust on one side and full reverse thrust on the other, at least for long enough to shut down the reversed engine.
  • This would appear, for aircraft certified for inflight reverser use, to essentially eliminate the danger of loss of control (absent other serious failures) in the event of a go-around after thrust-reverser deployment.

This would be especially important for aircraft like the Tu-154, Il-62, and Trident 1C, which routinely deploy their reversers before touchdown; if going around after reverser deployment was prohibited for such aircraft, this would seem to completely preclude very-low-altitude go-arounds with these types.

Are aircraft certified for in-flight thrust reversal (and, thus, not equipped with an in-flight reverser lockout mechanism) allowed to go around even after the thrust reversers have been deployed?

1: There is generally an override switch in the cockpit that can be used to restore pressure to the reverser actuators even when airborne (its main use is to force the reversers to remain stowed if one or more should come unlocked in flight, or to restow then in the event of an uncommanded in-flight deployment), but locating and actuating this switch would take precious seconds which might not be available in the event of an asymmetric reverser deployment at low altitude in an aircraft not certified for the inflight use of reverse thrust (especially as, during the time spent with their actuators depressurised, the deployed reverser(s) would be blowing back to the fully-deployed position, taking them further and further from the stowed position).

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    $\begingroup$ I'm not aware of any condtion where you would be allowed to initiate a GA at all when you are at that point in a landing. Even a GA initiated right at touchdown, called a "Balked Landing", is something you would initiate long before you even get the reversers out. Once you ave all three wheels down and are deploying them, you are committed. $\endgroup$ – John K May 26 '20 at 2:49
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    $\begingroup$ However, @JohnK, as pointed out in the OP, some aircraft intentionally use reversers while still in the air as part of their routine landing procedure. I think the question would be best served by some editing to focus on the GA procedures for these aircraft (Tu-154 & Il-62). Asking what the GA procedure for these (or similar) is once the reversers have been deployed, but while the aircraft is still in the air. (Maybe eliminate the initial paragraph to avoid confusion.) $\endgroup$ – FreeMan May 26 '20 at 15:46
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    $\begingroup$ This question is ANSWERED in the first link. One engine producing reverse thrust with the other at high thrust is a recipe for asymmetric thrust far beyond any VMCA. Even if certified for in-flight deployment so as to come down quickly (C-17, for instance), the asymmetric issue can still kill you. As explained in the Duplicate question. VTC. $\endgroup$ – Ralph J Jun 1 '20 at 3:06
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    $\begingroup$ @RalphJ: Yes, and the reason asymmetric reverse thrust is such a danger on go-around is because, in most aircraft, the reverser actuators are locked out when airborne, meaning that any reversers still in transit at liftoff will blow back to the fully-deployed position when the aircraft lifts off and the reverser actuators are depowered, resulting in reverse thrust (potentially asymmetric) on those reversers' engines. This failure mode does not exist on aircraft where the reversers are not locked out when airborne - i.e., aircraft certified for inflight reversing. Not duplicate. VTRO. $\endgroup$ – Vikki - formerly Sean Jun 2 '20 at 20:21
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    $\begingroup$ So say you are approaching in a Tu-154, just deployed reversers over threshold as usual, and suddenly the controller shouts in the radio GO AROUND, I REPEAT GO AROUND and you notice some other aircraft failed to observe a hold short instruction and is taxiing onto the runway about midfield. Is that an example of what you have in mind? $\endgroup$ – Jan Hudec Mar 19 at 7:50

An aircraft approaching to land with a reverser deployed or unlocked, particularly one that's deployed unintentionally, will be at idle power, or shut down on the deployed reverser.

A go-around or missed approach is conducted in the same manner as if the engine is shut down for any other reason.

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    $\begingroup$ I don't think this really answers the question - yes, if you had a malfunction prior to the go-around, you'd have shut down the engine with the malfunctioning TR. But he's asking how would the go-around be conducted $\endgroup$ – SSumner Jul 20 '20 at 0:32
  • $\begingroup$ I answered the question correctly. It would be very unwise to go missed approach with a reverser deployed, but if it were deployed, and a go-around required, the same procedure is used as a go around with that engine inoperative. The engine is shut down. The go-around is conducted on the remaining engine(s). Increasing airspeed will increase the drag effects of the engine with the reverser deployed. In my current airplane, after the basic procedure is performed, the FCOM states, "Continue use of affected engine at Captain's discretion." $\endgroup$ – Will Apr 15 at 9:18
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    $\begingroup$ If the engine is still in operation, which might be the case only if there is no buffet, aircraft behavior doesn't indicate the reverser is actually deployed, or other evidence indicates its not actually deployed, then it will be used as needed; this presupposes that it's only an indication problem. Otherwise, if the engine has been shut down, the missed approach is flown the same as any other missed approach with that engine shut down, being mindful that the drag increase is more than with an engine simply shut down. Flap use may be restricted during the approach. $\endgroup$ – Will Apr 15 at 9:23

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