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I have seen airplanes on YouTube and even in my country doing a touch-and-go.

I don't know why planes come down from thousands of feet just to touch the runway and then fly away:

  • Is it for show?
  • Is it to check the landing gear?
  • Is it because of a malfunction?
  • Does it increase the use of fuel?

Why do planes make a touch-and-go?

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    $\begingroup$ There are different possible reasons, so you're most likely to get an answer that's relevant to you if you tell us more about the context of your question. Have you seen some airplanes doing this recently? What kind of airplanes, where, and when? $\endgroup$ – Dan Hulme Sep 2 '18 at 9:20
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    $\begingroup$ to expand on Dan's comment: if you do not specify, the answer would need to be too long, and thus the question could get closed as too broad. $\endgroup$ – Federico Sep 2 '18 at 10:19
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    $\begingroup$ I believe the main reason for touch and go is pilot training (mostly on smaller planes though). Then there’s probably tests of new aircraft. There’s air shows. There are also aborted landings, but it’s probably rare that they actually touch in those cases. $\endgroup$ – jcaron Sep 2 '18 at 12:27
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    $\begingroup$ At my home airport, we regularly get airliners doing touch & goes for crew training. It’s the quickest way to get the aircraft positioned for another approach, and thus best use of time when training approaches. $\endgroup$ – Cpt Reynolds Sep 2 '18 at 12:43
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    $\begingroup$ And then there's the exceedingly rare case where the crew is getting landing gear failure indicators and want to test whether the gear is actually locked before making the landing. $\endgroup$ – jwenting Sep 3 '18 at 4:51
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To practice approaches, traffic patterns and landings without the added downtime of taxiing back for another takeoff. Pilots have to maintain proficiency in these skills by practicing them on a regular basis and touch and gos are some of the best ways to do this. It can also be used for meeting regulatory currency for carrying passengers depending on local time and landing gear configuration of the airplane. In terms of gas consumption, it’s no less wasteful than a stop and go or a taxi back. It’s not just for small aircraft either. I’ve seen plenty of large military aircraft doing pattern work like that as well as there is no substitute for the real thing. Airliners occasionally do touch and gos, but generally as part of a test flight after major maintenance; company pilots will fly approaches and landings in a level D full motion simulator simply because it’s cheaper and can simulate a wide range of conditions and emergency contingencies as well.

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    $\begingroup$ A full stop and taxi is also wastes a lot of time - not just the taxi time, but after a full stop it is mandatory to repeat the full set of pre-takeoff checks. The main use of touch-and-go in commercial aviation is in qualifying new pilots - actually being on a real flight deck is a very different psychological experience from being in a flight simulator, where however badly you mess up, you aren't going to die, or wreck a plane costing millions of dollars. $\endgroup$ – alephzero Sep 2 '18 at 16:50
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    $\begingroup$ Not necessarily. Some checklist items eg runup checks can be bypassed as already completed and most pre-takeoff checks can be as simple as flaps, lights, transponder, go depending on the airplane in question. As for a real full motion sim dedicated to aircraft type being different from the real thing, most pilots will complete their initial and recurrent type ratings in sims, not to mention most practice flying will be done there as well. It’s VERY close to the real thing. $\endgroup$ – Carlo Felicione Sep 2 '18 at 17:28
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    $\begingroup$ Training flights are a major difference between the US and Europe. Traditionally, EASA and its predecessors have required 6 real takeoffs and landings for a type rating, one of which must be full-stop. If the pilot has >500 FH in a similar plane, this is reduced to 4 (AMC2 ORA.ATO.125(k)). FAA has allowed full simulator courses for a long time, EASA has only started to introduce this with special approval in the last 10 years. $\endgroup$ – user71659 Sep 2 '18 at 18:08
  • $\begingroup$ A full stop also means you must taxi back to the head of the runway to takeoff again; you probably can't just take off from where you stopped, unless you're a C-130 on the Forrestal. $\endgroup$ – Harper - Reinstate Monica Sep 2 '18 at 20:18
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    $\begingroup$ @CarloFelicione I think Harpers point was that's a big "if" for anything large $\endgroup$ – Dan Sep 3 '18 at 8:52
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Practice, practice, practice

I drive by a regional Air Force base and I regularly see them doing touch-and go's with C-17s, C-5s, KC-10s and other commercial models in military gray. Since my drive-bys aren't that long, and I often see them, it's clear they do it all day.

Flying is a perishable skill (meaning you must constantly retrain or you lose it). There's a word for that -- Think of the word "current" as in "up-to-date", then think of how "fluent" becomes "fluency" -- the result is currency, the word for having up-to-date-ness. It also means money, but not here.

Currency is easy enough for a 2-pilot regional-jet crew that lands 4 times in a shift (2 landings per pilot per day). It's a lot harder for a 4-pilot transcontinental jet crew (main, relief) that does 17-hour flights, and lands once a day. (1/4 landing per day).

What's more, not every airport is friendly to touch-and-gos because they simply don't have the runway slots to spare. At JFK, you'd get a mouthful from ole Kennedy Steve. "fuggedaboutit!" Meanwhile some minutes' flying north, at Mirabel, you can have the airport to yourself.

To some extent, simulators are allowed to fill the gap. Otherwise it must be made up with practice flights, touch-and-gos and landings.

A problem

A commercial jetliner will do a "go-around" even after touchdown

  • if the tower tells them to
  • if something is squirreled about their touchdown, like they are too far down the runway and don't have enough left for comfort
  • if they actually meant to abort the landing before touchdown, called "go around" and punched up TakeOff/GoAround power, but they touched before the engines fully spooled up -- this might be because of weather, e.g. crosswinds exceeding the pilot's comfort level (google "manchester go-around" for lots of these).
  • if they see some sort of traffic contention on the landing runway, e.g. The landing aircraft ahead of them fails to vacate the runway fast enough, or an itchy Cessna at a cross taxiway seems to have missed the stop line
  • some other warning, e.g. ATC says "Delta 551, take Bravo (taxiway) to Delta, clear to cross runway 13” and they're landing on 13 right now

It's not for the landing gear. They have indicators in the cockpit for the landing gear. Some have inspection windows, periscopes or cameras so gear can be checked from inside. Otherwise they rely on external inspection: fly by the tower or a chase plane. If they just can't tell, they land anyway, expecting gear to collapse and hoping they won't. How the plane behaves with a collapsed gear is not a surprise; manufacturers design and test so the airplane can land safely with a broken gear.

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  • $\begingroup$ As far as I remember there is one more reason close to point two but not exactly - if the touchdown ended up in a bounce (that is it was to strong and plane wheels didn't stay on the ground) the pilot is obliged to make a go-around. This is an aftermath of one of the accidents, where pilots didn't realise they are not on the ground after a bump. $\endgroup$ – Ister Sep 3 '18 at 14:52
  • $\begingroup$ @Ister That rule certainly does not exist for all airplanes. I'm not sure if it exists for any of them. That would be a questionable rule for airliners especially, since many of them automatically deploy spoilers when the main gear hits the ground. If you can find a source for that, though, then it would be a good idea to add it as a separate answer along with the aircraft type(s) and conditions under which that requirement exists and, ideally, a link to a source to read more. $\endgroup$ – reirab Sep 3 '18 at 20:59
  • $\begingroup$ The human feedback loop that follows a bounce is pretty deadly, though. I could imagine a fleet operator (perhaps smaller planes) putting out a blanket order to go-around after a bounce rather than attempt to recover (and fall into the feedback loop). $\endgroup$ – Harper - Reinstate Monica Sep 3 '18 at 21:02
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Planes do make a touch-an-go mainly for two reasons:

  1. For training purposes, practicing takeoffs and landing (mostly in small planes)
  2. If the pilot flying cannot determine that the landing, rollout and full stop can safely be completed. One example is an icy runway with a thin layer of snow on it. It looks like it has snow but as soon as the plane touches it, it slides and is in the jeopardy of rolling/sliding off the runway on the side. in this case s/he simply declares a missed approach and takes off.
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    $\begingroup$ "an icy runway with a thin layer of snow on it" Hopefully in that case, ATC informed the pilot(s) about poor runway traction during the approach, so the pilot flying would be prepared for the situation. $\endgroup$ – a CVn Sep 10 '18 at 14:11
  • $\begingroup$ ATC actually did not inform my flight once in STL - a B747 arriving from HNL - which after touching the surface and noticing the conditions, did declare missed approach and proceeded to it's alternate, MCI $\endgroup$ – studio1057 Oct 24 '18 at 17:33

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