6
$\begingroup$

Pilots normally receive landing clearance for a specific runway assigned by ATC. Absent an emergency, can pilots of commercial flights (depending on the wind conditions for example) choose

  • a different runway
  • the landing direction for this runway
  • or both ?

If no, why not ?
If yes, (and still assuming nothing is wrong with the aircraft) how does the pilot get his wish ? Can (s)he ..

In the last 2 cases, does the pilot need to name a specific reason ?

$\endgroup$
3
$\begingroup$

To avoid all the Class this and that stuff, just think of controlled (tower with a clearance required) and uncontrolled airports.

If a controlled airport, the runway is assigned by the tower controller, normally based on the favorable wind. Normally, you use the runway assigned by the controller, unless you have a reason to use another one. Thing is, you don't HAVE to do what the controller says if it puts you in danger, and the controller doesn't HAVE to let you go where you want if it screws up his/her flow, and you could say there is always potential for a Mexican standoff situation, in theory. In practice, there will be some mutually agreed resolution, the controller wanting everything to flow smoothly and safely, and the airplane crew wanting to get where they're going without getting violated and without being forced into something dangerous.

So say you are given a clearance to land on runway 9, landing east, but you want to land on runway 18, landing south. So you ask for 18 and see if you get it. The controller decides whether it will cramp his/her day and says yes or no (probably yes 99% of the time). If no, your choices are to either land on 9, go elsewhere, or declare an emergency, in which case the decks are cleared for you but you may have to justify yourself later. In the big picture, common sense is supposed to prevail.

At uncontrolled airports, it's uncontrolled, so knock yourself out. You land on whatever runway you feel like, keeping in mind certain rules and protocols for uncontrolled aerodromes, like pattern (circuit) rules, IFR arrival announcement requirements etc etc. Say everybody is landing on 9 and you want to land on 27 going the other way, forcing an airplane landing on 9 to take evasive action. Probably you'll just get the finger from someone, but there's a possibility somebody will report you for breaking regulations on traffic etiquette and you will have to answer for it, but there is no ATC around so trouble won't come from them.

$\endgroup$
  • 1
    $\begingroup$ My home field is completely uncontrolled, single runway 04/22 with adjacent grass strips parallel to it. At one point when I was doing touch-and-gos on 04 in calm weather (originally the winds favored takeoff on 04, then died down almost completely), another aircraft decided to take off on 22. That made things quite interesting, to put it mildly. Nothing happened, but it definitely increased my cockpit workload for that circuit to rather close to my comfort maximum. $\endgroup$ – a CVn Jan 7 at 15:17
9
$\begingroup$

Pilots can request a particular runway approach course and landing but in a controlled environment they are at the mercy of ATC. At high traffic (read busy) commercial airports they are unlikely to get their request. As far as I know, shy of an emergency declaration you cannot insist on a non standard runway and expect to get it.

At a quiet class C or D airport they may very well get what they ask for. I did this a lot during my training at a quiet class D airport. If the winds were favorable to one runway but my instructor wanted to practice cross wind approaches we would request the non standard runway and if no one was around they would often grant it.


Generally you don't want to fly the non preferred runway if there are windy conditions as landing with a tail wind can be dangerous.

$\endgroup$
  • 2
    $\begingroup$ @summerrain you request a specific side of a given runway not a runway then a side. The phrase request a particular runway implies a given side of it. For example at KPNE there is RW 6 and RW 24 they are physically the same asphalt but requested by their headings. $\endgroup$ – Dave Dec 30 '18 at 3:22
  • 1
    $\begingroup$ In contexts where direction matters (most things related to takeoffs and landings), we consider each strip of pavement to be two different runways, e.g. Rwy 6 and Rwy 24. In contexts where it doesn't matter (like pavement type or dimensions), we consider the strip to be one runway, e.g. Rwy 6/24. $\endgroup$ – StephenS Dec 30 '18 at 4:52
  • 1
    $\begingroup$ @summerrain The most important condition when landing is the wind. The controllers at the airport choose the landing direction so that the aircrafts can land against the wind leading to slower ground speed at touchdown. At an uncontrolled Airfield the pilot is the only one responsible for his action. The controllers just give advices, not instructions. So the pilot could decide to use the opposite direction, but unless being in trouble, why should he? $\endgroup$ – Timothy Truckle Dec 30 '18 at 10:43
  • 1
    $\begingroup$ @summerrain One might say "strip" when the direction doesn't matter (e.g. a "single-strip airport"), but I think that's slang. "Runway" is used officially for both meanings, and context makes it obvious (to us, at least) which was intended. $\endgroup$ – StephenS Dec 30 '18 at 19:35
  • 1
    $\begingroup$ @summerrain Actually, if you're cleared for 6, then presumably others are using 6 as well, so 24 is likely to be refused as unsafe, whereas 12 and/or 30 (depending on winds) have a decent chance of being approved. $\endgroup$ – StephenS Jan 2 at 2:43
2
$\begingroup$

[Adapted from a comment I previously posted]

I have an anecdote which bears on this, at least for the case of takeoff. In 1988 I was on a flight leaving O’Hare and the radio comms were on one of the audio channels while we waited to taxi. Among the traffic we heard was something which caused me a bit of concern: a pilot being told to use a runway he thought was too short. He started off requesting "runway ZZ" and the controller simply responded "prepare to taxi to runway AA". After a second similar request that was also refused ("ignored" may be more accurate), the pilot said, Tower, I am X thousand lbs, I need Y thousand ft, I need runway ZZ. The controller finally agreed, with real annoyance in his voice.

I've long since forgotton the exact runway numbers, and I don't know whether the current runways have evolved since that time, but then as now O'Hare was a busy place, so I can easily imagine that allowing an oddball departure on a cross runways would require significant delays. Still, I was struck by how this pilot had to really insist on the runway he needed.

Within the same 20-minute session we also heard a pilot barge into a queue, in front of a plane he was clearly (twice) told to get behind. The tower said "get in behind the Company Nine" and in this big Texas voice the pilot responded "Roger, in front of the Company Nine"; tower said "negative, behind the Company Nine" and the pilot came back "Yessir, right in front of the Nine" and the Tower just said "Ok, fine.". So maybe there's a culture of low-grade pushiness that the controllers are prepared for.

And they lost track of a plane, telling an aircraft to queue behind another that just wasn’t in the queue at all. Which objectively seems kind of odd, too, but it was the least of it that evening.

$\endgroup$
  • 1
    $\begingroup$ +1 thank you for the great anecdote taken right out of real life, which sometimes is different than in textbook ... $\endgroup$ – summerrain Jan 2 at 1:33
  • 2
    $\begingroup$ KORD had lots of intersecting runways, so an unplanned arrival or departure on the wrong one(s) is extremely disruptive--and KORD didnt have much spare capacity. Part of the recent upgrades was to remove some of those runways and replace them with more (and longer) parallels to avoid exactly this problem while increasing total capacity. $\endgroup$ – StephenS Jan 2 at 2:50
  • 1
    $\begingroup$ There's a similar problem at KJFK; in one particular flow, the runways used for landing are not long enough for an A380 to land when wet, forcing those flights to divert. Part or the problem is KJFK can't change their flow without KLGA and KEWR also changing theirs, and coordinating all that likely takes longer than the fuel reserves of the flight that can't land. $\endgroup$ – StephenS Jan 2 at 2:56
  • 1
    $\begingroup$ @StephenS: interesting, so how is the problem you describe solved at KFJK ? $\endgroup$ – summerrain Jan 2 at 3:21
  • 2
    $\begingroup$ @summerrain A380 flights divert to an alternate airport in that case. They avoid using that flow when the runways are wet, but sometimes there's just no choice. $\endgroup$ – StephenS Jan 2 at 15:47

Your Answer

By clicking "Post Your Answer", you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.