Less than 40 seconds.

That’s how long Air India Flight 171 remained airborne before it crashed into a crowded neighborhood in Ahmedabad—marking one of the most confounding aviation disasters in recent Indian history.

Now, investigators face the urgent and difficult task of piecing together what caused the Boeing 787 Dreamliner to fall from the sky moments after take-off. With 242 people aboard and nearly 100 tonnes of fuel, the London-bound aircraft had barely cleared the runway when a mayday call was sent out—its final transmission before the plane plummeted, erupting into flames.

A Rare and Puzzling Crash

“This is the rarest of the rare,” says Captain Kishore Chinta, a former investigator with India’s Aircraft Accident Investigation Bureau (AAIB). “To my knowledge, nothing quite like this has happened—a controlled flight into terrain just seconds after departure.”

Theories under review range from dual engine failure due to bird strikes or fuel contamination, to improper flap configuration, to critical maintenance oversights—or even pilot error, such as accidentally cutting off fuel supply.

Air crash investigators work methodically, relying on physical evidence, technical data, and process of elimination to establish the chain of events that led to the crash. And in this case, the investigation is already well underway.

Focus on the Engines

Early insights are likely to come from examining the plane’s two engines. “You can tell from the damage whether the turbines were producing power at the moment of impact,” explains Peter Goelz, former managing director of the U.S. National Transportation Safety Board (NTSB). “If they weren’t, attention immediately shifts to the cockpit.”

Turbine blades behave differently at high rotational speeds versus idle or failure states. These clues can help determine if power loss played a role.

Decoding the Black Boxes

The aircraft’s Enhanced Airborne Flight Recorders—commonly known as “black boxes”—have already been recovered and are being analyzed at the AAIB lab in Delhi. These recorders hold key data, including cockpit conversations, engine performance, control inputs, and ambient cockpit sounds.

Flight data may show, for instance, whether the engines were at full thrust, if flaps and slats were deployed correctly, or if an automated system misfired. Any anomalies could point to mechanical fault, pilot misjudgment, or even a deeper issue within the Boeing 787’s advanced flight management system.

“If the data leads to a fault in the flight control system,” says Goelz, “then this could raise red flags beyond just Air India—affecting Boeing’s global fleet.”

No Immediate Red Flags

So far, officials say there’s no sign of systemic fault. India’s civil aviation ministry reported that a recent review of Air India’s Dreamliner fleet found no major safety concerns, and that maintenance protocols were in compliance with standards.

Boeing President and CEO Kelly Ortberg confirmed the company is cooperating with Indian authorities, as required under international aviation rules.

A Global Investigation Team

While India leads the probe, international collaboration is already in place. Experts from Boeing, engine manufacturer GE, Air India, and Indian regulators are joined by investigators from the U.S. NTSB and the U.K., given the aircraft’s destination.

“The how is often determined quickly,” Goelz notes. “But understanding why takes time.”

What Happens Next?

Investigators are meticulously combing through the wreckage, collecting every bolt, wire, and fragment. The remains of the aircraft may be reconstructed in a hangar to visualize the crash sequence—though this may not be necessary if the black boxes yield sufficient data.

Fuel systems will also be scrutinized. Investigators will check for contamination in filters, valves, and lines. Sources say the refueling equipment used before departure has already been inspected and likely quarantined.

Digging Deeper into Records

Investigators will now turn to the plane’s history—reviewing maintenance logs, pilot-reported defects, and ACARS data (a system that relays real-time technical information via satellite). They’ll analyze recent flights by both the aircraft and its crew, as well as pilot training, simulator performance, and emergency preparedness.

All replaced components will also be traced to identify any recurring faults or overlooked issues that may have contributed to the crash.

“This process is painstaking, but modern technology has revolutionized it,” Goelz adds. “Back in the ’90s, flight data recorders tracked just a handful of parameters. Now they capture thousands every second. That level of insight changes everything.”

Timeline Ahead:

• Preliminary report: Expected within 30 days (as per ICAO rules)
• Final report: Typically published within 12 months
• Ongoing risk assessment: Depending on findings, could impact airline protocols or manufacturer standards globally