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Suppose, if the Airport has only one runway and one plane is trying to take off at the end of the runway and other plane trying to land from the other end of the runway.

Due to any reason if the pilot decides to abort the take off.

In that situation that plane is blocking the runway and it is in the way where the other plane is trying to land at the same time.

What action will be taken by the pilot who is landing the plane and what action will be taken by ATC?

Is there any chance of collision?

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    $\begingroup$ I don't think this is a duplicate. The linked question is asking what happens if a runway is closed well in advance of aircraft that want to land; this question is asking what happens if an aircraft unexpectedly blocks the runway while another plane is trying to land. $\endgroup$ Aug 27, 2019 at 18:10
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    $\begingroup$ I read the question as one plane land and one plane takeoff from opposite end of the runway. This would not happen at controlled airport. $\endgroup$
    – vasin1987
    Aug 27, 2019 at 19:57
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    $\begingroup$ The scenario is unlikely because starting and landing, at least on controlled airports, happen in the same direction; even on uncontrolled airports they normally would with any wind that's not exactly perpendicular to the runway. (That said, an aborted start would still block the runway even if being in the same direction.) Oh, @vasin made that point already, partly. $\endgroup$ Aug 28, 2019 at 14:11

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ATC will tell the landing plane to go-around. The pilot will then execute the go-around by flying the missed approach procedure as published in the airport charts.
Go-arounds happen daily and are pretty much a routine action.

In any case, if the landing pilot feels that the runway is not safe for landing, he can decide to go-around by himself without ATC order (if the controller missed the issue or if the airport is uncontrolled for example).


For reference, the missed approach procedure can be as simple as:

  1. Stopping descent
  2. Climbing back to a published altitude
  3. Flying a published pattern
  4. Trying a second approach
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    $\begingroup$ And the landing plane should be able to see the plane on the runway as it approaches. Ideally, you wouldn't want to commit to a landing approach while another plane is visibly on the runway. $\endgroup$
    – user12007
    Aug 27, 2019 at 15:12
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    $\begingroup$ @Snow I edited my answer to reflect your comment. Thanks! $\endgroup$
    – Quentin H
    Aug 27, 2019 at 15:19
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    $\begingroup$ @Deepak-MSFT "what if landing plane is just about to touch the ground and it can not abort the landing" - there is no point where the landing cannot be aborted, up to and including when wheels have touched down. There comes a point where you have reduced speed so far as to not have enough runway left to take off again, but in the situation you supply, this is not possible. $\endgroup$
    – Jamiec
    Aug 27, 2019 at 15:19
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    $\begingroup$ I suggest you clarify that "go-arounds" happen daily and are routine, but not for reasons of runway incursions, which are quite rare and extremely serious. $\endgroup$
    – abelenky
    Aug 27, 2019 at 15:42
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    $\begingroup$ @abelenky done ;) $\endgroup$
    – Quentin H
    Aug 27, 2019 at 15:44
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one plane is trying to take off at the end of the runway and other plane trying to land from the other end of the runway

That would never happen. Planes are under ATC control from the moment they start their engines until the moment thay shut down their engines at the destination. (This is a simplification, but for the context of this question it makes sense).

ATC decides basically everything a flight does: which way it taxies, where and when it takes off, which way it flies, how high, how fast, when and which runway to approach and when to land. ATC will always ensure that there is enough separation between flights so that there is no risk of collision. That is literally the main reason ATC exists.

Generally speaking, only one aircraft is allowed on any one runway at a given time. While a plane is taking off from a runway, another plane cannot be cleared to land on that same runway. The aircraft approaching will not be cleared to land until the departing plane is in the air. If the departing plane decides to abort takeoff, ATC would simply instruct the landing plane to cancel the approach, and then direct it around for another try.

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    $\begingroup$ That would never happen INTENTIONALLY. There are plenty of examples of situations where due to some reason or another 2 planes ended up on the runway at the same time, although this usually is caused by extreme fog conditions, in which case the pilot probably wouldn't be able to see the obstruction. $\endgroup$
    – Nzall
    Aug 28, 2019 at 11:50
  • $\begingroup$ @Nzall Sure. As stated, my answer is a simplification. $\endgroup$ Aug 28, 2019 at 12:49
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    $\begingroup$ It may never happen in theory,but does happen in practice, I witnessed myself once.A BA flight to Nassau stopped its landing (it was night, I am not sure how close we were, but clearly the ground was visible) and regained altitude. First announcement: we had to cancel the landing for security reason, more details later. Second announcement: since it is dark, there was a plane on airport ground whose location is not known precisely so to avoid hitting it on the runway if it is there we decided to cancel the landing and go around. Second landing was fine. Of course, it is only what we were told. $\endgroup$ Aug 28, 2019 at 16:35
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    $\begingroup$ Also the airtraffic is monitored, but not really controlled by ATC in the sense that the pilot flying has the absolute authority, where to fly. ATC simply tries to manage the requests and proposes flight paths that conform to established routes. Still the rest of your answer applies. +1 $\endgroup$
    – Spacy
    Aug 28, 2019 at 16:54
  • $\begingroup$ @PatrickMevzek Uhm yes. That's exactly what I wrote in my answer. If the runway is blocked, ATC will instruct the pilot to cancel the approach. Exactly as you experienced. $\endgroup$ Aug 28, 2019 at 17:26
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The air traffic controller will instruct the landing aircraft to perform a go-around.

It is part of the air traffic controller's job to ensure there is always enough spacing between a departing aircraft and a landing aircraft to accomodate such a situtation.

A situation similar to what you describe is in this youtube video:

Note that in this case the clearance to land was given before the departing aircraft left the runway. This is quite normal in the USA, but not allowed in many countries.

Usually the clearance to land is only given after the departing aircraft (or previously landing aircraft) has left the runway. The landing aircraft is cleared for the approach to the runway, but not for the landing itself, until the runway is clear. Should the departing aircraft be stuck on the runway, and the communication to the approaching aircraft fails as well, the situation is still safe since the approaching aircraft is not cleared to land and will therefore have to go around.

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    $\begingroup$ Is 'clearance to land is only given after the departing aircraft has left the runway' a European rule? I fly in the US as and land at Class D and Class C airports. I am often given a clearance to land as number 3 or 4. e.g I am told to follow a Cessna on 4 mile final. I report them in sight, then I am told, “Cleared to land number three.” I also get cleared to land and they inform me that several aircraft will be departing in front of me. $\endgroup$
    – JScarry
    Aug 27, 2019 at 17:53
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    $\begingroup$ @JScarry not so much European, many countries operate this way. US is the best known exception, but there may be others. $\endgroup$
    – DeltaLima
    Aug 27, 2019 at 17:56
  • $\begingroup$ ICAO rules prohibit clearing more than one aircraft to use a runway at a time. The FAA, however, allows it in many cases under their "anticipated separation" rule. $\endgroup$
    – StephenS
    Aug 28, 2019 at 14:46
  • $\begingroup$ @StephenS Indeed, ICAO describes it almost to that effect: ICAO Doc 4444 (PANS-ATM) section 7.10.2 (Clearance to land) states: An aircraft may be cleared to land when there is reasonable assurance that the separation in 7.10.1, or prescribed in accordance with 7.11 will exist when the aircraft crosses the runway threshold, provided that a clearance to land shall not be issued until a preceding landing aircraft has crossed the runway threshold. $\endgroup$
    – DeltaLima
    Aug 28, 2019 at 14:51
  • $\begingroup$ @DeltaLima I've been "number 8, cleared to land" while in the pattern. There is no way you can do that under ICAO rules. $\endgroup$
    – StephenS
    Aug 28, 2019 at 15:13
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This doesn't just happen, it is a situation that develops. That developing situation will be watched closely by ATC, who will communicate with the approaching aircraft.

"Its speed was mini"

Note how the approaching aircraft can hear ATC trying to talk the A318 off the runway. Also notice how they call "go-around" (abort) immediately after "Minimums" is called out. Minimums is the normal decision point where you abort the landing if the aircraft isn't positioned, configured and stabilized, the runway isn't seen, runway isn't clear etc.

Double trouble: Route interference

There's actually a worse situation than what you propose. You have the aircraft NOT taking off, and we've shown that's straightforward. What if it does successfully take off?

Now we have a route conflict and a collision risk, not just on the ground, but in the air. Watch this.

Green (Ukraine) was lined up for takeoff, but wasn't fast enough to get out of purple's way. *At this point, it is a foregone conclusion that purple (KLM) MUST go around.

But there's a problem. On a standard go-around, you fly runway heading - climbing over the runway and continuing that "line". That means for Purple to go around, Green must not be in that air! That's why Green was ordered to stop and hold on the ground even though he'd already started his takeoff roll.

Unfortunately Green had some "radio trouble", and continued the takeoff anyway. He would be in exactly the on-runway-heading space that Purple needed to "go around" in.

So ATC made an urgent radio call to Purple telling him to immediately turn to another heading. "Go around, immediate right turn heading 010". If that radio contact had failed, Green and Purple would be flying in the same airspace, and relying on visual observation to miss each other.

It was presumed that Green was unreachable because of his "radio trouble". Just as likely, Green realized that if he aborted takeoff here, he'd have to pull off to a ramp, work a hot-brakes procedure, and then get back in the queue to takeoff at this busy airport, with an hour or even more delay, maybe with disruption to the schedule for the rest of the day. So he decided to have "radio trouble" and let ATC clean up the mess. That's no way to make friends in the tower!

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It can happen at uncontrolled (no ATC tower) as well (which are the vast majority of airports in the US). Initial reaction is to apply power to help with a climb and then start "cleaning up" the airframe - retracting landing gear (if so equipped), start flaps retraction (and slats, etc) and continue climbing. At some point, make an announcement on CTAF ("Marlboro traffic, Nxxxxx is going around") or the same to the tower ("Worcestor tower, Nxxxxx is on the miss" if shooting an instrument approach, or "Worcestor tower, Nxxxxx is going around" if VFR, tower will likely provide directions.

The situation can happen at either end of the runway.

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This recording from Prague airport captures similar situation as you described - El Al took too long to takeoff and separation with CSA on final could no longer be guaranteed. ATC cancelled the takeoff for El Al and ordered the CSA to go around.

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