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I know that most aircraft have a warning system which makes beeping sounds if an aircraft tries to land without the gear down. After reading this news article about an Air India flight 676 flying without retracting the landing gear, I was wondering if there is a reverse mechanism which warns the pilots if the landing gear is not retracted during flight?

If its not there, why?

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  • $\begingroup$ I believed that landing gear has a speed limit and the overspeed warning would sound if you exceeded the speed ... ? $\endgroup$ – yo' Aug 20 '17 at 21:44
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    $\begingroup$ I can guarantee you, at least on 747-100/200 aircraft, that if you somehow didn't get the gear up, it would only be a matter of seconds or a minute at the most, before all 3 cockpit crew members started wondering what the hell was wrong with the aircraft. The mismatch of the crewmembers' internalized expectation of what the performance should be versus what was actually happening would be all but impossible to ignore. $\endgroup$ – Terry Aug 21 '17 at 0:11
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    $\begingroup$ Indication that it is extended, yes. Warning that it is extended (when it shouldn't be), no. Other than significant noise, drag, poor performance, high fuel consumption, etc etc tc. That a qualified airline crew could miss this is one of those head-shaking, fouled up beyond belief, maybe time to consider finding a new career sort of moments. $\endgroup$ – Ralph J Aug 21 '17 at 3:12
  • $\begingroup$ I'd guess that any crew that doesn't notice the position of the gear lever, or the unusual flight characteristics of the aircraft, or the different noise it makes flying with gear extended, is also to not going to notice a warning beep/horn... $\endgroup$ – jwenting Aug 21 '17 at 5:51
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    $\begingroup$ @RalphJ: This is an expected behavior from pilots of an airline which is having an $8bn debt. $\endgroup$ – Nitish Aug 21 '17 at 6:02
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It's not there because it's like driving with the handbrake on.

[The flight] was climbing out of Kolkata, however achieved an unusually poor climb rate, was not able to accelerate to normal cruise speeds and leveled off at FL200 after a continuous climb for about 30 minutes (avherald.com).

And because the flight crew should have run the 'after takeoff' checklist, which includes checking that the landing gear is up and locked.

enter image description here
(Source) A typical Airbus A320 checklist.


Related: How much extra drag does landing gear incur?

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  • $\begingroup$ I'd say that there's no warning beeps because it's not a dangerous situation. You wouldn't want a pilot ignoring a warning beep when they assume it's just the undercarriage warning. $\endgroup$ – user12007 Jul 26 '17 at 9:42
  • $\begingroup$ @Pete It would have been a dangerous situation, if there were no airports nearby. The aircraft was running low on fuel. Imagine it happening somewhere over an ocean. I don't know much about aviation, so my assumptions might be wrong. $\endgroup$ – Nitish Jul 26 '17 at 9:51
  • $\begingroup$ As ymb1 indicates in his answer, a change in handling characteristics and unusual fuel usage would become apparent after a while. There's separate warnings for stall risk/low fuel levels. $\endgroup$ – user12007 Jul 26 '17 at 9:57
  • $\begingroup$ I'd say a warning light/alarm for the flaps would also be a smart idea. I flew from San Francisco to LA once and noted the flaps were still extended a few degrees the whole flight... They did not fully retract till after the landing. I'm guessing the pilot knew something "felt wrong" since after we landed ground crew wandered around the aircraft scratching their heads.. $\endgroup$ – Trevor_G Jul 26 '17 at 12:33
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I flew the light-attack, single-seat jet the A7-E while stationed aboard the Nimitz. The landing gear position indicator indicated both up-and-locked as well as down-and-locked. That doesn't mean it got much attention on the takeoff though.

I was a new pilot attached to the squadron when one of the senior JO's left for a cross-country. He was climbing to altitude when he called maintenance to discuss a problem he was having. "There seems to be something wrong with the engine," he exclaimed. Maintenance asked him what the signs were and he replied that it just wasn't generating enough thrust. "I can't seem to get above 220 KIAS, and my climb rate is very low." A series of questions followed: What is your fuel flow? Turbine outlet temperature? Altitude? Throttle position? Any unusual noises?

His answers seemed to suggest that everything appeared normal. Nothing was out of the ordinary. As we listened to the radio conversation a pilot off in the corner, with a big smile on his face, suggested he look at his lading gear position indicator.

"Hey maintenance, I found the problem. See you in a few days."

In either position, down-and-locked or up-and-locked there was no audible tone. There was just a visible indication. One was expected to follow their checklists and look at the indicator.

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Some of the comments about that incident indicated there is an illuminated light, at least in some aircraft, indicating the gear is down, but not an audible tone.

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  • $\begingroup$ FAR §91.205 requires "Landing gear position indicator, if the aircraft has a retractable landing gear." On GA aircraft, that is either one or three lights. On mine, it is green for down and orange-yellow for up. $\endgroup$ – JScarry Jul 26 '17 at 13:32
  • $\begingroup$ @JScarry the position of the landing gear lever is a pretty good indicator too :) $\endgroup$ – jwenting Aug 21 '17 at 5:50
  • $\begingroup$ @jwenting If you have a Johnson bar gear lever, you can tell the position. Not so easy on my Cessna. touringmachine.com/images/Gear_Handle_Cessna210.jpg $\endgroup$ – JScarry Aug 21 '17 at 15:22
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There is a saying "There are 2 kinds of retract pilots - those who have already landed gear up and those who are putting it off until later".

To prevent this the Piper Arrow had a system which would actually lower the gear automatically if you got into a situation that it thought was landing (low speed, low power setting) but had not yet lowered the gear. Sounds great!

The main problem with this is that in the event of an engine failure, you would be in exactly this condition; but, since gear down is EXTREMELY drag producing (that being the point behind raising gear in the first place) it would severely limit how far you can glide (cuts it by about 70%). Several people had engine failures and unintentional gear extensions and were forced to make off-airport landings as a result, when odds were good they could have made an airport if the gear had stayed up until the last minute. Turning it off immediately became an additional step in the engine failure emergency checklist, the very last place you want additional tasks.

To my knowledge the Arrow was the only plane with this system on it. Piper never tried it again. Most of the Arrows I have flown have had the system removed (which is bad because some of them did and some did not so I would be extra-stressed in an emergency to lock out the system, but might not need to).

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  • $\begingroup$ I'm not sure how this answers the question, which is about retracting the gear, not lowering it. $\endgroup$ – Pondlife Jul 5 at 15:40

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