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Tyre/wheel damage, retract the landing gear?
A320 specific but suppose it can apply to any aircraft....
The following question was inspired by a dream last night. I woke up before it turned into a nightmare! :) Well actually, it's a scenario I've experienced in the sim in the past but it got me thinking. We don't take this scenario nearly as seriously as other things. Just before V1, you hear a bang, followed by a judder and an ECAM warning WHEEL TYRE LO PR . You rotate, PM calls "Positive Climb". Question: Would you want to raise the landing gear? (assuming not performance limited for departure). Of course it would be unwise to continue to destination with this condition. There is potentially a lot of damage to the tyre, wheel and more. My biggest concern is that by raising the landing gear, we would be taking all that mess into the wheel hold, risking either the doors not closing/opening properly or the gear unable to extend later on. The tyre(s) and wheel(s) could be cooked, and we would be bringing it all closer to the fuel tanks. The FCOM and FCTM doesn't advise on the matter. The landing gear question (to raise or not to raise) needs to be answered pretty early on but SOP demands it is retracted 5 seconds after lift off. Any thoughts? |
If you have an indication as you describe, SOP goes out the window. Leave gear extended, unless a greater emergency (such as inability to climb) dictates otherwise. I am surprised that the FCOM does not advise on this. Normally performance does not assume compound failures, ie it will cover failure of either one engine or gear retraction, but not both. Engine failure would degrade performance more than leaving the gear down. But, to achieve a safe flight path with gear extended, flying the OEI departure may be preferable to staying on the SID. Of course if you are having a bad day and an engine swallows whatever blew the tire and fails, you do whatever it takes to not hit the ground, which may well mean retracting the gear. |
Interesting scenario.
From time to time trained in our SIM programm (major EU carrier). Tyre may have dammaged hyd lines, linkages, etc. So recommendation was to keep the gear down as you are returning anyway. |
Is there automatic braking of the whell at retraction?
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Originally Posted by FlightDetent
(Post 10488614)
Is there automatic braking of the whell at retraction?
Can be seen on that A330 video. |
If you’re climb limited you should have briefed an engine out special procedure. Leave the gear down and fly the engine out procedure. You may consider a departure alternate as the airport you’ve departed from may not always be the most suitable to return to. |
I was wondering about this decision: Incident: Nordica CRJ9 at Kiev and Tallinn on Jun 4th 2019, burst tyre |
You might get the gear up but space isn’t that generous in the wheel well and any major deformation of the tyre could easily prevent it from extending again if broken tread snags on something in there. Dispatch with a U/S brake calls for a delay in gear retraction to allow the affected wheel to slow down, however immediate retraction is allowed in the event of an engine failure. The performance penalty when applying the MEL is considerable. In this situation I would not retract the gear unless I absolutely had to and would definitely be flying the EOSID if terrain was a factor. |
Very most A320 ies don't have that tyre pressure indication system, so you won't possibly know about the failure at that time.
When the tower informs you about tyre pieces in the runway the gear is up anyway. In this case my company even recommends to continue to your destination, as coming back to land overweight with tyres missing is not likely to be a better scenario. |
When in doubt, delay, if possible, the gear retraction due to the possibility of a landing gear fire. Back in July of 1991 Nigeria Airways Flight 2120 (operated by Canadian company, Nationair) crashed soon after departure from Jeddah, Saudi Arabia, killing all 261 people aboard. Under-inflated main gear tires overheated, failed and caught fire during the takeoff run. The burning gear was retracted into the wheel wells, eventually melting structure and penetrating a fuel tank.
Grog |
Originally Posted by CW247
(Post 10488551)
A320 specific but suppose it can apply to any aircraft....
The following question was inspired by a dream last night. I woke up before it turned into a nightmare! :) Well actually, it's a scenario I've experienced in the sim in the past but it got me thinking. We don't take this scenario nearly as seriously as other things. Just before V1, you hear a bang, followed by a judder and an ECAM warning WHEEL TYRE LO PR . You rotate, PM calls "Positive Climb". |
Inhibited from 1st engine TOGA to 1500 ft or 20 sec after liftoff (do not quote me on the time limit).
Brakes HOT is different, inhibit releases at lift-off. Does not change his point. If damage to tyre suspected, retract or not? The concern is of course the extension after that. |
FD, thanks for clarification. In this context TOGA=FLEX (?)
Anyhow, at 1.500ft, or 20 sec after liftoff, the gear will already have been retracted, unless there is a NON ECAM assumption of a blown tyre. |
Originally Posted by FlightDetent
(Post 10489960)
Inhibited from 1st engine TOGA to 1500 ft or 20 sec after liftoff (do not quote me on the time limit).
Brakes HOT is different, inhibit releases at lift-off. Does not change his point. If damage to tyre suspected, retract or not? The concern is of course the extension after that. |
gearlever Indeed, my bad. FCOM DSC-31-15 "D" INDICATIONS ON E/WD - Flight Phases
(could someone please dig the time limit, or am I imagining things...) https://cimg0.ibsrv.net/gimg/pprune....8f9cfbde99.png Similar to your remark, I am afraid that if you really had a burning spray of leaking hydraulic fluid, the BRK temp sensors wouldn't pick it in time due to airstream cooling. Bang, the doors close. But there is a reason we do not have a fire DET loop in the bay, so trust in the engineers need to keep you safe. |
I know someone who took out a runway edge light on departure but decided to continue with the flight to home base.
On landing he discovered rather too late there was a brake problem and the aircraft departed the left side of the runway, skidded across the grass and came rather close to hitting a light trainer carrying out engine checks on the "lazy link" prior to departure. Had the pilot of this second aircraft not been alert and taken off across the taxyway and across the grass parallel to the runway in use (!) there might have very serious consequences. The aircraft was a red Hawk with white stripes.....no names mentioned but there are quite few identical ones! |
Not forgetting of course that debris from a damaged tyre could impact the flaps, flap tracks. Until further diagnosis available it may be advisable to not retract the landing gear or the flaps. if engine damage occurs caused by tyre debris, then all bets are off and the pilot must make an informed decision. There are too many variables to commit to hard and fast rules.
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Originally Posted by Centaurus
(Post 10490235)
Not forgetting of course that debris from a damaged tyre could impact the flaps, flap tracks. Until further diagnosis available it may be advisable to not retract the landing gear or the flaps. if engine damage occurs caused by tyre debris, then all bets are off and the pilot must make an informed decision. There are too many variables to commit to hard and fast rules.
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Performance problem
We had exactly this problem on a twin (MD80) in GVA - RW 23. A tyre blew as we rotated but the first cockpit indication we had was a jolt in yaw and popping left engine. Immediate actions for engine failure on take off were Gear Up and check TO thrust set on the live engine - the popping engine ran OK in flight idle, where we had set thrust. Those who know GVA know that the single engine climb out is terrain limited and exactly defined. With the gear up we just made the required min alt for the left turn. After gear retraction we had a red on the left main, so taken together with the engine problem I had the first thought that a tyre burst could have occurred. The popping engine was caused be the L spray deflector having been torn off and entered the L intake, where it sat over the static vanes and restricted the flow but we didn’t know that until subsequent trouble shooting in the PAS hold and coordination with the cabin chief, who could see the rubber through a pax window. There was also other serious damage, so the story goes on but the only relevant bit here is that the gear had to be retracted in order to get over the hill. If you have this happen somewhere there is no single engine problem and you are pretty sure that a tyre has burst, then don’t retract. Problem is, will you know in time to make that decision? |
Had a A320 tyre deflate on take off, nothing noticed until after a normal landing the ship was a bit right wing down. Hole in the wing, engine reverser and rubber behind the fan which might have all been done on landing. |
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