India, July 4 -- Keystone Law, a major London law firm, on Thursday, listed two very 'serious' questions in the London-bound Air India AI171 plane crash soon after take-off from Ahmedabad three weeks ago that killed 260 people.

This comes as the law firmannounced that it has been formally retained by a number of British families who lost loved ones in the crash to address "serious questions" once the preliminary report into the investigation is released.

According to the PTI report, Keystone Law said its aviation team, supported by international experts in the field, is focused on two specific areas of concern: the "cause of the Ram Air Turbine (RAT) deployment, and then the sequential loss of thrust in both engines."

The firm's aviati...