Capt. Sumeet Sabharwal, 55, had been considering early retirement to care for his octogenarian father. His co-pilot for the day, Clive Kunder, 32, had just started to build momentum in his career.

Together, they brought nearly 10,000 hours of flight experience to the cockpit. But now it is the final moments of their last flight, the ill-fated Air India Flight 171, that investigators will be studying for months to come. The flight, which took off on Thursday from Ahmedabad City bound for London, lasted less than a minute in the air before crashing into the campus of a nearby medical college, leaving at least 270 people dead.

The impact ignited a fireball so intense that the bodies of most of the victims are damaged beyond recognition, officials have said. By Sunday morning, three days after the crash, the remains of only 19 onboard the Boeing 787 had been identified through DNA tests and released to the families.

Investigators have sealed the crash site and the hostels of the medical college that were hit. They have recovered the aircraft’s flight data recorder and continue searching for the cockpit voice recorder. They hope the conversation between Captain Sabharwal and First Officer Kunder, along with other information recorded in those devices, known as black boxes, can shed light whether the plane crashed because of mechanical failure, human error or some other combination of factors.

Regardless of what went wrong, officials and experts agree on one point: the pilots had virtually no time to regain control of the plane as it began going down.