FAA issued an SAIB in 2018 about these fuel control switches being installed without the locking feature engaged\x97Air India didn\x92t act on it (not mandatory).
No evidence of birdstrike, fire, or mechanical failure. Both engines had good health data. The only obvious explanation at this stage is an inadvertent dual shutdown by crew,
We are talking about the Engine 3 position stop/run/start switches here? SB stopping engine shut down if thrust lever are beyond flight idle? Blimey, seen a photo of the switches in question. Assume they are detented? Actually why are they not guarded?
Last edited by Diff Tail Shim; 11th July 2025 at
21:18
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Actually, why are switches that are only really required on the ground or in an engine shut down event where they are? Embraer's have the switches out of the way on an overhead panel and as well as detent locked, have a protective guard, one has to physically lift. If the PF had to physically carry out the engine shut down on an Embraer, he would have to raise his arm. Would be obvious to the PnF.
Last edited by Saab Dastard; 11th July 2025 at
21:55
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Reason: Deleted post quote removed
The landing gear lever is forward and up on the centre instrument panel, adjacent to the PFD. The fuel control switches are aft and low, on the thrust pedestal. There's no reasonable way to confuse one for the other in terms of position, hand movement or 'muscle memory'.
No there is not. Further investigation will likely see if the locking detents were in a decent state or not. TBQH, such a switch should be properly guarded. Like a Embraer is, like other types that one sees with switches one has to lift a guard to operate and is locked on with the guard in position. Boeing designers found out again in not making processes fool proof?
The report mentions that the immediate prior flight crew had written up a "STAB POS XDCR" status message, and that troubleshooting was carried out.
Is it possible that the troubleshooting/diagnostics left the stab cutout switches on the pedestal in the cutoff position, which went unnoticed until liftoff (i.e. upon noticing that the trim wasn't operable), resulting in a reach towards those switches, which are situated right next to the engine cutoff switches?
Like this? Actually, the middle switches should look like the port side ones IMHO. Properly guarded.
Fuel switches are NOT toggle switches precisely because aircraft designers mitigate against brain farts involving simple switching actions.
Those switches are lift to move. They were lifted to shut off and thrown back to start in the report. No CVR or FDR trace is going to explain why two switches were throw by error or by intention. Only a video would. PnF would have had his eyes outside or on instruments for the calls. As mentioned, other manufacturers put such switches out of harms way for general use. QRH is the only reason to go to them.
Spoken to a rated mate whom is current on 78s and he told me that inadvertent operation of a fuel shut off in flight has happened with a switch being knocked past its detent (lock) by the switch being caught by a crew bag.
I cannot imagine a situation where any pilot would be moving a crew bag within seconds of getting airborne.
Nor do I. It was just a point that such switches can be knocked off inadvertently. Of course in this case, it seems a deliberate action, either by mistake or deliberate thought. If the FO did it, the Commander picked it up very quickly from first signs of roll back. Saw switch positions, asked question, got wrong answer and tried to resolve the situation. Full report will mention who said what. Two types I am rated on have the start stop switches overhead, are detented to operate and have a sprung loaded cover over them. From what I have heard, inspection of the integrity of said switches has already been raised.
Last edited by Diff Tail Shim; 12th July 2025 at
09:20
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The Indian AAIB are avoiding a German wings event I fear. Actually I was in a flight deck of a EJR today. Start / stop switches are so bloody obvious on the overhead as main switches. Guarded and easy to observe by all. Control switches that are not required as a normal action put away from hidden positions and visible to all. Embraer actually design systems logically. Speaking to a Captain today, he confirmed that if the the thrust levers of an EJR are beyond flight idle, engines cannot be shut down by then engine start/stop switches being turned off! You need to drag the thrust levers back to idle to shut them down. First thing I was taught as an airframe engineer converting to dual trade is that the fuel system of a airframe should not restrict an engine to receive fuel from a commanded input by the pilot. Throttle position should drive that logic. Not a lazy Boeing combined FADEC and SOV switch.
