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Are there situations in which a pilot could/has to lower the landing gear during flight for reasons not directly connected to landing? (i.e., not part of the landing checklist)

Originally I thought I had seen some around the location indicated by the pin on the map below (17° 25' 30.093" N, 78° 32' 27.4734" E), in the evening time around 4:00 and the weather was clear.

Sighting location

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That's nowhere near midflight. You are seeing aircrafts approaching Begumpet Airport (VOHY)'s runway 27. This airport has no airline service, but it is used for some general aviation including VIP flights and as military airbase.

The point directly north (about 3 km) from the coordinates you gave (N17° 25' 30", E78° 32' 27") is about 6 km, or 3.2 nm, from threshold of VOHY runway 27. Given usual 3° glide slope the aircraft would be just about 1000 ft above runway elevation, which happens to be the latest point where landing checklist should be complete. Yes, that means gear down. It also means it will be touching down in about a minute and a half.

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Yes. If you want to increase drag to lose altitude quickly. For example, mountain flying, need to descend rapidly and speed brakes + flaps just aren't cutting it.

Fun fact: The F4U Corsair used its landing gear as speed brakes. There was a special way they lowered them in this case. (I belive the hydraulic struts weren't locked ect., so landing on them would not be smart)

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    $\begingroup$ Common during emergency descent procedures. Get down to gear & flap operating range, drop them, tight spiral dive at the highest speed permissible in that configuration. $\endgroup$
    – Brian Knoblauch
    Aug 12, 2014 at 16:20
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    $\begingroup$ Military uses this technique when needing to to land at a front line airfield and straying too far from the field will be dangerous. $\endgroup$
    – Bassinator
    Aug 12, 2014 at 16:33
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The reasons I can think of offhand for extending the gear for other than landing are:

  • As has been mentioned in a previous answer, use of the landing gear as a speed brake. The Fokker F-27 had a speed brake switch on the front panel that when used lowered the main landing gear but left the nose gear retracted. At the two 747 carriers I worked for in the 1990s, we occasionally dropped the gear to get more drag for a steeper descent. As I remember the max gear extension/retraction speed was 270 knots, but once extended the max speed was 320 knots.
  • To cool hot brakes or hot tires. This was the most common reason in my experience for extending the gear. The 747-100/200 was supposed to be taxied at no greater than 25 kts, which meant that braking was needed during taxi even with engines at idle. Tire flexing also produced significant heat. There was a recommendation not to taxi more than 30,000 feet as I remember because of these factors. If you were using, say, the reef runway at Honolulu, you exceeded that distance by the time you lifted off, and if you were above 800,000 lbs you were guaranteed serious heating.
  • To pre-cool the brakes and tires if you had a short leg followed by a quick turn. The 747 was originally designed to stay in the air for awhile before landing. The story I most often heard was they designed for 5.5 hours of cooling in the wheel wells before the gear would be used.
  • To burn extra fuel to get below landing weight. Rare, but it could happen if you were tankering fuel such to arrive at max landing weight and for whatever reason the leg burn was less than planned. Fuel burn increase with the landing gear down is quite dramatic. We were tankering fuel once from Yakota, Japan to Osan, Korea, and we couldn't get the landing gear up. Our choices were to dump fuel and return to Yakota or to proceed to Osan with the gear down. We chose the latter. We couldn't get above 25,000 and our fuel burn was twice normal. Confused the controllers; they kept wondering by we were so slow and so low. We kept having to explain.
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Landing gears are generally retracted to decrease drag in flight . As the speed of an aircraft increases, so does parasite drag. Mechanisms to retract and stow the landing gear to eliminate parasite drag add weight to the aircraft.

Private Jets generally use Tricycle-type landing gear with dual main wheels . One of the main advantages of using the Tricycle-type landing gear is that it prevents ground-looping of the aircraft. Since the aircraft center of gravity is forward of the main gear, forces acting on the center of gravity tend to keep the aircraft moving forward rather than looping, such as with a tail wheel-type landing gear.

It is not necessary to retract the landing gear . Infact there are Landing gears that are Fixed as can be seen in many small, single engine , light aircrafts .

On certain occasions Private jets as well as large aircrafts like the Boeing 777 extend their landing gear during flight to cool the Brakes because :

  1. The brakes may have been heated by the previous landing and not had time to cool while the airplane was at the gate.

  2. During taxi out, they were further heated by necessary brake applications.

  3. After takeoff, the landing gear retracted into the wheel well where there is limited cooling air.

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    $\begingroup$ Do you have a reference (e.g. an operations manual) for extending the gear during flight for this purpose? Many aircraft have speed restrictions for extending or retracting the gear that would make this unfeasible during cruise. $\endgroup$
    – casey
    Jul 31, 2014 at 16:12
  • $\begingroup$ @ casey - I have a couple of Aircraft Operation Manual . They are all in paperback . The only Manual in pdf format is this deltava.org/library/B777%20Manual.pdf $\endgroup$
    – DSarkar
    Jul 31, 2014 at 16:41
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    $\begingroup$ That "manual" is produced by flight sim enthusiasts and doesn't address the in-flight gear extension. If one of your manuals does address it, I'm willing to bet it is in the QRH under abnormal/emergency procedures. In bullet points #1 and #2 of your list, an airplane would delay its takeoff if the brakes were too hot to ensure adequate performance to abort the takeoff at V1. I'm still quite skeptical that outside of an in-flight emergency (brake overtemp/fire, emergency descent, etc) that anyone is dropping the gear during cruise. $\endgroup$
    – casey
    Jul 31, 2014 at 20:18
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    $\begingroup$ After takeoff, the landing gear retracts into the wheel well where cooling air is limited . This will cause the brake hot light to illuminate the sensor and generate an Electronic Centralized Aircraft Monitoring (ECAM) alert if the temperature exceeded 300?C. Consequently,the crew would follow the ECAM procedure and extend the landing gear, allowing the air to cool the brakes. $\endgroup$
    – DSarkar
    Aug 1, 2014 at 7:03
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    $\begingroup$ @D_S: Therefore it is nowhere near cruise but only during climb-out. $\endgroup$
    – Jan Hudec
    Aug 1, 2014 at 15:37
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I am on a U.S. Air flight right now. Pretty sure that the plane is an A330. About 20 minutes after take-off, the pilot said that he had to lower the landing gear to cool off the brakes. After about 3 minutes of much noise, and some chop, he raised them and said that it had worked.

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    $\begingroup$ That is quite out of the ordinary, but it happens sometimes when turn around times are short or there was an aborted take-off. Heat dissipation from the brakes can take quite some time so it normally the measured maximum brake temperature occurs quite a while after the brakes were applied. Usually under such circumstances the gear is not retracted immediately after take-off, but what you describe is not unheard of. $\endgroup$
    – DeltaLima ♦
    Jun 17, 2015 at 21:30
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    $\begingroup$ And welcome to Aviation.SE. $\endgroup$
    – DeltaLima ♦
    Jun 17, 2015 at 21:31
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I cannot imagine much need to lower the gear during flight, except perhaps if there was an issue. Also doing so mid flight would required restricting speed to the lower of Vlo (landing gear operating speed) or Vle (landing gear extended speed).

The actions that one takes that involve dropping the gear are usually part of some error handling procedure. These may be documented in operational manual or be something defined during training on the specific aircraft.

The one time I dropped gear in flight it was after one of the gear lights failed to turn off (indicating gear up and stowed) after retract. I slowed up to stay within the operational limits, dropped the gear and then retracted the gear. This time the gear light stayed off. After landing I checked the gear switches for a stuck piston or loose wire. I did not find anything and the problem never repeated.

If the problem had been something like a gear motor circuit breaker popping I would have reset the breaker ONCE. If the breaker popped again I would have cranked the gear down and left it down.

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Sure it's a private jet? Plenty of single-engine piston powered aircraft have fixed landing gear.

Most jets cruise at high altitudes, so if you can a) see the aircraft, b) identify it as non-commercial, c) notice the landing gear is down, and d) claim that it's not near an airfield then it's more likely that it is a 4-6 seat piston single with fixed gear. Cessna, Piper, Beechcraft have made thousands.

Addendum to edited question: You say there are no airports near by. Possible there's one a little further away? Planes typically raise the gear as soon as they are off the runway, but they lower it 30km out. And that's 30km flying distance, not driving diatance.

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  • $\begingroup$ a)It's a commercial jet with twin engine plane(a kingfisher plane) b)its a medium sized plane not too small(a trainer craft with prop in the centre) or not too big (Airbus A380). $\endgroup$
    – user285oo6
    Jul 28, 2014 at 11:32
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    $\begingroup$ You missed the other option: that it is nowhere near midflight. $\endgroup$
    – Jan Hudec
    Jul 28, 2014 at 15:18
  • $\begingroup$ @JanHudec yes, his statement that it's "clearly visible from 30 feet" made me frown at the "mid flight" bit. $\endgroup$
    – jwenting
    Jul 29, 2014 at 7:29
  • $\begingroup$ @jwenting what made you frown a bit $\endgroup$
    – user285oo6
    Jul 29, 2014 at 7:45
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    $\begingroup$ @jwenting The claim is that he saw it while standing on a terrace 30ft above ground level, not that the plane was 30ft AGL. $\endgroup$
    – David Richerby
    Jul 29, 2014 at 20:31

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