India’s air crash investigating agency and a pilots’ group on Thursday pushed back against what they described as premature and unfounded attempts to assign blame to the crew of Flight AI171 that crashed in Ahmedabad last month.
The Aircraft Accident Investigation Bureau (AAIB) said that selective and unverified reporting could mislead the public during an ongoing probe. The Airline Pilots Association of India (ALPA-I), which represents over 1,000 pilots, said the crew deserved respect and not unfounded character judgments.
Their statements have emerged amid speculation by some pilots and crash investigators outside India that one of the pilots of the Air India flight shut off fuel to the engines — a theory now echoed by foreign officials familiar with the investigation.
The Wall Street Journal, quoting people familiar with US officials’ early assessments of the crash probe’s findings, said on Wednesday that dialogue between the flight’s two pilots, captured by the cockpit voice recorder, indicated that it was the captain who had turned off the fuel switches.
A family member of Akash Patni, who died after burning debris from the crashed plane fell on him, garlands his photo in Ahmedabad on July 13. Reuters
“The first officer who was flying the Boeing 787 Dreamliner asked the more experienced captain why he moved the switches to the ‘cutoff’ position after it climbed off the runway,” the newspaper said.
“The first officer expressed surprise and then panicked, while the captain seemed to remain calm.”
Experts from the US Federal Aviation Administration and the National Transportation Safety Board were among participants in the crash investigation conducted by
the AAIB.
The AAIB on Thursday accused certain international media representatives of “attempting to draw conclusions from selective and unverified reporting”, and said such actions “are irresponsible especially when the investigation remains ongoing”.
In its preliminary report on the crash, released on July 12, the AAIB had said the switches that control fuel supply to the engines had “transitioned” from “run” to “cutoff” moments after takeoff, and within a second of each other.
One pilot had asked the other why he had “cut off” and the other responded that he had not, according to the report, which did not specify who said what.
Between 9 and 13 seconds later, both switches moved back to “run” and both engines relighted — but the plane, which had begun losing altitude even before it had crossed the airport perimeter, was flying too low to recover from its fall.
The AAIB said that while the accident had drawn public attention and shock, “this is not the time to create public anxiety or angst towards the safety of the Indian aviation industry, particularly on the basis of unfounded facts”.
“The purpose of the preliminary report is to provide information about what happened,” the AAIB said. “At this stage, it is too early to reach any definite conclusions. The investigation by the AAIB is not complete. The final investigation report will come out with root causes and recommendations.”
ALPA-I members have expressed anger at the speculation by fellow pilots and former crash investigators, mainly outside India, that a pilot on AI171 — likely the captain — had switched off the engines.
“The crew of AI171 made every possible effort — till their very last breath — to protect the passengers on board and minimise harm on the ground,” the ALPA-I said in a statement on Thursday.
“They deserve respect, not unfounded characterjudgments.”
Some pilots in India and other aviation experts have over the past five days argued that an electrical malfunction, flawed switch behaviour, or a software glitch may have caused the engines to lose thrust before the flipping of the switches.
Others, including pilots and former crash investigators, believe that details in the AAIB’s preliminary report — both what is said and what is left unsaid — offer clues to the sequence of events leading up to the crash.
The clues
- The report says the two switches “transitioned” to cutoff with a one-second gap — a term questioned by pilots who assert that the switches require human manipulation to be flipped.
Some experts in India have argued that electrical malfunctions or a short-circuit could have sent faulty signals that shut down the fuel supply valves, causing the engines to lose thrust.
But Greg Feith, a former crash investigator in the US, has underlined that a faulty circuit cannot explain how the engines came back on when the switches moved back to their “run” positions.
“How did it magically open to allow fuel to go back to the engine for the restart to occur?” Feith said on the YouTube channel, Flight Safety Detectives.
Two US pilots, Steve Scheibner and Ryan Bodenheimer, have cited the one-second gap between the two cutoffs as another clue pointing to pilot manipulation.
- The report says that Captain Sumeet Sabharwal was doing the monitoring while co-pilot Clive Kunder was flying the aircraft. Scheibner, Bodenheimer and others say this line provides information on whose hands were free to manipulate the switches three seconds after takeoff.
The copilot would have had his hands on the aircraft’s controls, and Sabharwal’s hands would have been free.
- The report does not document any event on the aircraft during the three seconds between 1:38:39pm, when the aircraft lifted off from the runway, and 1:38:42pm, when the fuel switch for Engine 1 was flipped from “run” to “cutoff”.
Had a software glitch, electrical malfunction or any other failure led to engine thrust loss before the switch flips, it would have been recorded in the digital flight recorder — and cockpit surveillance systems would likely have issued alerts.
The absence of such a record suggests that the aircraft was “operating exactly the way it was designed to operate”, Scheibner has said on his YouTube channel, Captain Steeeve.
- The report says one pilot asked the other why he had “cut off”, and the other responded he had not. Both Scheibner and Bodenheimer view this as an odd question. Had something gone wrong with the engines unexpectedly, the natural reaction would have been: “What happened?” or “Why did this happen?” — not “Why did you cut off?”
- The report says “at this stage of the investigation”, there are “no recommendations” for either the aircraft manufacturer Boeing or the engine maker General Electric. Some pilots view this as a hint of pilot fault.
Others argue that the absence of recommendations simply reflects that the probe has not — at this stage — found any aircraft or engine flaws. If such flaws had been detected, they say, they would likely have prompted a recommendation for corrective action.