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A Southwest airliner recently had an issue where a "deflated tire indicator" showed on one of the landing gear tires after takeoff from Oakland, CA. They circled nearby for 4 hours while burning off fuel before landing back at Oakland.

In a circumstance like that, where there's no flight control or aerodynamic problem (i.e. landing gear door stuck open), why wouldn't the flight continue on to the destination airport and burn fuel along the way? The flight time is close to the amount of time they spent circling to burn off fuel, so it's not like they get on the ground any faster by staying near their source airport.

Note that this particular plane landed safely and inspection showed no indication of any real issue with the tire, but even if it did have a flat tire, would it be any worse to go on to the destination?

I suspect that it may be just in case another in-flight emergency forces the plane to divert to an alternate airport that may not have the full emergency equipment to deal with a landing gear problem, which raises the question: if the flight had departed from a small airport with limited emergency support, would the plane travel to an alternate airport with better emergency support?

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    $\begingroup$ Unanswerable unless it is known whether the gear remained down. $\endgroup$ – Fattie Dec 24 '15 at 3:24
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    $\begingroup$ @JoeBlow: Answerable if the two options are discussed? $\endgroup$ – mins Dec 24 '15 at 13:59
  • $\begingroup$ hey @mins! this is not "my site", as it were, but it's always a shame to see answerers expending considerable amounts of expert time, on poorly-founded questions! I'm only a "friend of this site" observor but that's my take! (This is one of the few really good sites in the whole SO network, so it's a shame to see poorly-done questions.) $\endgroup$ – Fattie Dec 26 '15 at 18:54
  • $\begingroup$ Is destination better prepared to help with a possible belly landing? (Or to rescue passengers in case of a failed landing?) $\endgroup$ – jean Dec 29 '15 at 13:42
  • $\begingroup$ In the title, did you mean "why burn fuel at takeoff airport instead of.." (or similar)? $\endgroup$ – Lightness Races in Orbit Apr 24 at 17:41
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The issue here is threefold:

  • What exactly has happened? Has one tire simply deflated? Or more than one gone?

  • Has some other problem happened due to the event that led to tire deflation?

  • If you have a damaged tire during takeoff, you have one during landing and that is not a very good thing.

A tire deflation may indicate many things- one of the tires may have deflated or the tread may have given way, leading to debris (which will force a runway check)and damage. It is best to be cautious and asses the damage.

Also, there may be other damages to the aircraft (if for example, the tread has been damaged) which may manifest later on. For example, in a Boeing 737, tire failure lead to,

... the loss of the A system hydraulic contents, failure of the landing gear to retract...

Also,

Tyre debris had been flung upward and rearward, becoming lodged against the left rear spar close to aileron and spoiler control cables..

Unless you know for sure, it is better not to continue with the flight.

There is also this document that clearly says that in case of tire failure in takeoff (though I'm not sure how 'official' it is):

Always think twice before retracting gear and then flaps.

Also, landing with a burst tire will cause:

  • Possible loss of braking effectiveness

  • Difficulty in directional control during landing

among others. Better to be land back in the same airport rather getting diverted to an unknown airport which may or may not have the required facilities.

In the end, the decision to return to the same airport or continuing on is the captain's decision. for example, the captain of the B737 already referred declined to return to the airport (at first, anyway) though offered by the ATC.

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  • $\begingroup$ If there was a warning light but no indication of other failures (hydraulic, etc.) and they just did not want to retract the gear without knowing, is that something that might be able to be resolved by doing a fly by and having the tower look at it? I've heard of that happening with ga, but is that sort of thing ever done with the big jets? $\endgroup$ – TomMcW Dec 24 '15 at 20:43
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I have no idea what a deflated tire indication is on a 737, but perhaps the news media got something wrong in their reporting. (Nah... that never happens, does it???)

That said, the cardinal rule of landing gear problems is to leave a good configuration alone, so don't retract a gear with a possible problem, since it might not come back down again.

With the landing gear extended, your fuel burn per mile is far greater than with the gear up, so "enough fuel to get to XYZ" (based on normal gear-up cruise) isn't nearly enough to get there with the wheels down.

Any time an airliner takes off from a field they couldn't return to (most often, this comes up because the weather isn't good enough for a published approach back in), they have a "takeoff alternate" that they could get in to within a prescribed distance -- typically an hour's flying time.

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  • $\begingroup$ But assuming that the article is correct (there are some aftermarket tire pressure sensing systems for the 737) and the only problem was a suspected flat tire, why not go to the destination airport? I understand that if the gear is down, then that affect's the planes aerodynamics and it wouldn't be wise to proceed) $\endgroup$ – Johnny Dec 23 '15 at 21:55
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    $\begingroup$ @Johnny But why was the tire deflated? The crew did not have an answer to that question. If, as Ralph suggests, they hadn't raised the gear yet, then it would be a good idea to leave it alone. Maybe whatever deflated the tire also damaged the gear. $\endgroup$ – user19474 Dec 23 '15 at 22:26
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    $\begingroup$ @user19474 - Ahh, now that would make sense -- if the pilot saw the low tire pressure warning before raising the gear and decided not to raise the gear in case, for example, the tire blew out leaving loose pieces that might interfere with the mechanism preventing the gear from bring lowered again. $\endgroup$ – Johnny Dec 23 '15 at 22:47
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    $\begingroup$ Indeed, but even if he raised the gear before seeing the pressure warning, there's still the question of whether there was damage to the wing from whatever damaged the tire. If in doubt, get the aircraft back on the ground and check! $\endgroup$ – Jon Story Dec 26 '15 at 1:44

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