Boeing Dreamliner has a system capable of cutting fuel to the engines on its own
Aviation attorney and former US Department of Transportation Inspector General Mary Schiavo has cautioned against rushing to blame the pilots in the Air India crash. She pointed out that the Boeing Dreamliner has a system capable of cutting fuel to the engines on its own.
Pointing to past incidents involving Boeing 787s, she said known software-triggered engine issues — including systems that can cut fuel flow mid-air — must be thoroughly examined before drawing conclusions.
“In about 75% of the cases, the pilots are blamed — and in many cases, we’ve been able to disprove that,” Schiavo said in an interview with Barkha Dutt. “It is not only unfair but simplistic and harmful to blame the pilots… there are too many suspicious things to say, ‘Oh, it’s the pilots’.”
Schiavo pointed to prior incidents involving the same aircraft model where onboard systems, without pilot input, cut fuel to the engines mid-air. She cited a 2019 All Nippon Airways incident where a Boeing 787’s system mistakenly shut off fuel mid-air after misjudging that the aircraft had already landed. “That system — TCMA — has already been faulted in a prior incident. It can and will cut the thrust to both engines if it malfunctions,” she said.
“There have already been two interesting somewhat similar situations on the All Nippon Airways flight back in 2019,” she said. “As the plane was coming into land, the fuel control cut off occurred. The plane itself cut off the fuel to the engines. The plane came in like a very heavy glider, but because it was landing, not taking off, there was no crash.”
She also referred to a more recent case involving a United Airlines Dreamliner flight between Washington DC and Nigeria. “The plane itself put the plane into a nose dive. There was a thrust issue, there was an engine issue, and the plane experienced some deviations,” she said.
What happened in the All Nippon case?
Explaining the ANA case in detail, Schiavo said the Boeing 787 is equipped with several automated systems, including one mandated by the US Federal Aviation Administration (FAA) to help distinguish between flight and ground conditions. “This particular system wanted the plane to have the ability all by itself — pilots didn’t have to do this — to sense whether it’s in the air or on the ground,” she said. “And what happened in the ANA flight back in 2019 is the plane thought it was already on the ground and it was still in the air, and it cut the fuel.”
Such misjudgements can have serious consequences, she noted, particularly during takeoff, when aircraft have only seconds to achieve a stable rate of climb. “On takeoff, you don’t have that luxury,” she said.
What is TCMA?
At the centre of her concern is the Dreamliner’s Thrust Control Malfunction Accommodation (TCMA) system, a software protocol mandated by the US Federal Aviation Administration (FAA), which can command the aircraft to cut engine power under certain conditions. “The TCMA is a system that the FAA mandated so that the plane itself can assess when it needs to cut back the power. And that is tied in with the flight controllers, which are on both of the engines,” she explained. “This system, which has already been faulted in a prior incident, can and will cut the thrust to the engines both if it malfunctions and says it’s time to cut the thrust. And that has happened before.”
‘Not enough evidence to blame the pilots’
Schiavo criticised the rush to pin the Air India crash on the pilots, pointing out that such conclusions often come too early and derail a full investigation. “Just having one pilot allegedly say to the other, ‘Why did you do cut off?’ and the other one say, ‘I didn’t,’ that’s not nearly enough,” she said.
“There are experts whose job it is literally to listen for tiny inflections in the pilot’s voice, to listen for every click in the cockpit, to listen for everything that happens. Until that is done, and until we know whether the aircraft itself could have cut those switches — as it did in All Nippon Airways — it is unfair and simplistic to blame the pilots.”
Schiavo also invoked past examples where pilots were wrongly blamed. “In about 75% of the cases the pilots are blamed and in many cases… we’ve been able to disprove that,” she said. “Everyone remembers MH370. There was not a shred of evidence that the pilots did that intentionally and yet they got blamed.”
She cautioned that such investigations can take years. “The flight data recorder will have literally millions of lines of code and reported information. It’s the most advanced flight data recorder out there. Each of those will have to be examined,” she said. “In the case of a takeoff… pilots simply do not have the time and the altitude. Altitude is time. The higher you are, the more time you have to react.”
Until all these angles are explored, Schiavo says, “it is not only unfair, but it’s simplistic and harmful to blame the pilots.”
Reported on 17 July 2025 by Business Today.