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Regardless which tank is feeding the engines, it’s all from the same source pumped into the tanks during refueling.
Air India Flight AI171 (Boeing 787-8) Crash
- Thread starter john_pifer
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True. However in the event it was contamination separate tanks might result in one engine staying on longer than they other - likely depending on a bunch of factors. I would have to imagine in the Western world getting bad fuel is virtually impossible. In other places I wonder?
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We don’t have ANY information about fuel contamination in Airbus FCOM ( flight crew operating manual ).
I don’t think fuel contamination was a factor but the accident is so bizarre, who knows. I am sure they will check the fuel at the airport, that I can guarantee.
https://safetyfirst.airbus.com/fuel-microbiological-contamination-treatment/
https://mentourpilot.com/incident-fuel-contamination-take-off-engine-trouble/
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Early on there was speculation that there was a loss of power in both engines.
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That has always been the most logical explanation if you looked at the circumstantial data but it was too hard to believe a modern passenger jet could lose both engines right after takeoff off and instead focused on the flaps.
It all makes sense , especially why the landing gear wasn’t up ( RAT doesn’t supply enough hydraulic pressure ).
It’s not realistic to think any pilot that accidentally retracted the flaps wouldn’t realize ( or other pilot would catch it ) the mistake, put them back down and select the gear up as the other pilot applied full thrust.
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I got a chance to retract flaps instead of gear at pos rate in a level D Boeing wide body sim yesterday. Not a 787, but fwiw the error didn’t really matter that much. We used the same runway and weather as the accident. Even at structural max t/o weight, the jet pretty much out-accelerated the flap retraction. It got to about V2 - 10 at the lowest. By the time the flaps were more than halfway up the jet was accelerating well above V2 and never even came close to shaker.
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Update from the Aviation Herald:
On Jun 15th 2025 Government Officials reported the aircraft had a longer than normal takeoff run and used almost all of the 3505 meters/11499 feet long runway. 38 fatalities on the ground have been confirmed so far.
Apparently the aircraft used the full length for take off.
On Jun 15th 2025 Government Officials reported the aircraft had a longer than normal takeoff run and used almost all of the 3505 meters/11499 feet long runway. 38 fatalities on the ground have been confirmed so far.
Apparently the aircraft used the full length for take off.
Lots of theories on what went amiss. Usually focus one thing. The reality is planes crash due to two major issues/
And/or errors that happen not one.
And/or errors that happen not one.
He does make a compelling argument for the RAT being deployed, and I have to admit, it DOES sound exactly like a RAT (being in aircraft maintenance on Embraers, I have heard a RAT up close and personal many times, as we do test-runs of the RAT on the ground, using a hydraulic motor attached to a ground hydraulic test stand called a “mule”).
The RAT on the 787 is larger, but it sounds the same.
Believe me, when we run the RAT in the hangar, it is LOUD. We go around passing out earplugs to everyone.
And now more people than ever know what a RAT is!
What are the chances that no other plane had fuel issues and the problem being with the airport?
I waiting for data from the boxes. Until then it's not totally nailed down what happened.
I do have a question for those who know the mechanical details. If fully fuelled, then gases allowed to flow into the fuel tanks to make-up volume are critical for alowing sufficient fuel to continue to flow out of those tanks. I know inert gas systems may be used, which are more complicated that simply alowing ambient air in. So, if an inert gas system was not providing make-up volume as fuel left tank(s), would the engines run long enough to get into the air, and then reduce power because of fuel starvation. And if that happened, how would those engines run. I can imagine a lot of alarms going off in the cockpit in such a situation, and pilots working to figure out what's going on and what to do, being way too occupied to bring up the landing gear.
I mention the above because that aircraft may have been fully fulled. Lack of make-up gases into fuel tanks would present problems much earlier into a flight with full tanks, than if the tanks were not at full level.
Reminds me of the chapter in the book Fait is the Hunter where masking tape used to keep snow out of fueltank vents was left on and the aircraft crashed because fuel could not be drawn from tanks.
Of course my concern is just a speculation at this point. These aircraft are extremely complicated macheines. There's many critical systems that are a concern.
But maybe someone who knows the details can comment about this scenario.
Are the wing tanks ventilation tied to a common system? Are they filled with inert? Or is only the center tank supplied with inert make-up gases?
The previous flight had problems with the air-conditioning system. Would working on that AC system involve working near other critical systems such as the tank ventitalation?
Again just speculation at this point.
I do have a question for those who know the mechanical details. If fully fuelled, then gases allowed to flow into the fuel tanks to make-up volume are critical for alowing sufficient fuel to continue to flow out of those tanks. I know inert gas systems may be used, which are more complicated that simply alowing ambient air in. So, if an inert gas system was not providing make-up volume as fuel left tank(s), would the engines run long enough to get into the air, and then reduce power because of fuel starvation. And if that happened, how would those engines run. I can imagine a lot of alarms going off in the cockpit in such a situation, and pilots working to figure out what's going on and what to do, being way too occupied to bring up the landing gear.
I mention the above because that aircraft may have been fully fulled. Lack of make-up gases into fuel tanks would present problems much earlier into a flight with full tanks, than if the tanks were not at full level.
Reminds me of the chapter in the book Fait is the Hunter where masking tape used to keep snow out of fueltank vents was left on and the aircraft crashed because fuel could not be drawn from tanks.
Of course my concern is just a speculation at this point. These aircraft are extremely complicated macheines. There's many critical systems that are a concern.
But maybe someone who knows the details can comment about this scenario.
Are the wing tanks ventilation tied to a common system? Are they filled with inert? Or is only the center tank supplied with inert make-up gases?
The previous flight had problems with the air-conditioning system. Would working on that AC system involve working near other critical systems such as the tank ventitalation?
Again just speculation at this point.
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All aircraft fuel systems are equipped with vacuum relief valves should the normal venting system, be it inerting or simple atmospheric, is compromised.
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Exactly.
But IIRC someone said this plane had recently come out of maintence.
While I highly doubt fuel contamination was the cause, you can be the only plane to have fuel contamination problems like in the article below.
The flight below flew for several flights before it lost power at 500 feet.
Once again, I don’t think it had fuel contamination but I would never have believed what happened to this Airbus until I read the article.
https://www.flightglobal.com/safety...d-in-a321-dual-engine-incident/138004.article
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I am not sure.
edyvw
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Apparently RR. The airplane was acquired from a company, not directly purchased by AI. AI is using its 787 GE.
edyvw
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I thought FR24 had already established that a few hrs after the accident? Unless I am missing some development?
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This picture of Air India ship VT-ANB clearly shows that it was equipped with GEnx engines.
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