Air India's Chairman N Chandrasekaran on Monday told staff that last week's plane crash that killed at least 271 people should be a catalyst to build a safer airline, urging employees to stay resolute amid any criticism.

In a town hall held at the headquarters of the Tata Group-owned airline near New Delhi and attended by 700 staff, Chandrasekaran said the crash was the "most heartbreaking" crisis of his career, a spokesperson told Reuters.

"I've seen a reasonable number of crises in my career, but this is the most heartbreaking one," he said, according to a Tata Group spokesperson.

"We need to use this incident as an act of force to build a safer airline," Chandrasekaran told the meeting.

The Boeing 787-8 Dreamliner with 242 people on board bound for Gatwick Airport south of London began losing height seconds after take-off in Ahmedabad on Thursday, and erupted in a huge fireball as it hit buildings below.

All but one on board were declared dead in the world's worst aviation disaster in a decade, and around 30 people died on the ground.

The airline and the Indian government are looking at several aspects of the crash, including the plane's engine thrust, flaps, and why the landing gear remained open as the plane took off and then came down.

"We need to wait for the investigation ... It's a complex machine, so a lot of redundancies, checks and balances, certifications, which have been perfected over years and years. Yet this happens, so we will figure out why it happens after the investigation," Chandrasekaran, 62, said during the staff meeting.

He is also the chairman of the Tata Group conglomerate.

The crash poses a new challenge for both Air India which has for years been trying to revamp its ageing fleet, and Boeing, which is trying to rebuild public trust following a series of safety and production crises.

After taking the carrier over from the government in 2022, the Tata Group unveiled its investment plans to create a "world-class airline" after years of financial losses, persistent flight delays and poor maintenance under government ownership.

On Monday, an Air India Boeing 787-8 Dreamliner plane bound for New Delhi returned to its origin of Hong Kong shortly after takeoff following a technical issue.

"It's not easy to face criticisms," Chandrasekaran said. "We are going to get through this. We need to show resilience."

In Ahmedabad, dozens of anxious family members have been waiting to collect bodies of relatives killed in the crash, as doctors worked to gather dental samples from the deceased and run identification checks.

Only 99 samples have been matched so far, and 64 bodies have been handed over to the families, Rakesh Joshi, Medical Superintendent of a civil hospital in the city, said.

Authorities late on Sunday also said both the flight data recorder and cockpit voice recorder have been located and secured, which will be key in the investigation.