Leeham News and Analysis

Little known, most unknown in Air India 171 crash

By Scott Hamilton

June 13, 2025, © Leeham News: One day after the crash of Air India flight 171, very little is known about what happened. Almost everything remains unknown.

What we know

• This is the first fatal crash of a Boeing 787. The accident airplane was delivered in 2014 and is a 787-8,
  

  A screen show of a video of Air India flight 171. The camera is from a distance and the quality is grainy, but to many this seems to show that that flaps were not extended for take off. However, some flaps positions are set at 5 degrees, and may not be readily visible in this shot.

  the first sub-type of the family of airplanes.

• There were 242 passengers and crew on board. One passenger survived; there were fatalities on the ground, but the number is fluid. One news report cited a total of 290 killed in the plane and the ground.
• Two videos of the accident surfaced yesterday. One shows the plane’s final seconds as the flight appeared in a relatively flat-attitude climb followed by a slow descent into the ground and explosion of fuel. The other showed the 787 on its take off roll, ascent, descent and crash. Both show that landing gear remained down throughout the short flight. The grainy videos appear to show the flaps were not extended for take off. The second video shows what appears to be a lot of dust thrown up as the plane lifted off the runway. Some speculate that was from the runway overrun area, but the angle and distance from the CCTV doesn’t include this detail.
• A Mayday call was sent from the flight. Most reports end with this one word. A few said the words “no power” were included in the Mayday.
• The weather was clear, but it was humid and more than 100 degrees in temperature. These hot conditions extend take off rolls.
• The plane was headed to London, some 10 hours away. A heavy fuel load would be on the plane.

The speculation

• The videos appearing to show the flaps were up led to the possibility that for some reason the plane was not properly configured for take-off. A flapless take off often leads to crashes, and the presence of a cloud of dust as the airplane lifted off could lend credence to a flapless roll. Flaps up after lift off could lead to a stall.
• However, past accidents with misconfigured flaps and slats included a wobbly take off and immediate crash within the airport perimeter. The video shows a smooth climb, such as it was, and smooth descent, suggesting the pilots retained some control over the airplane.
• “No power” in theory points to a problem on the take off roll, as well as a climb out. “No power” can mean any number of things: complete failure after lift-off, or reduced power at a critical point of the take-off and short flight.
• Fuel contamination could be a factor, but investigation will look into this possibility.
• The landing gear remains down throughout the flight. Normally, the gear would be raised right away. This leads to speculation of a hydraulic issue or perhaps the pilots mistakenly raised the flaps instead of the gear.

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