When Sagar Patel’s mother boarded Air India flight AI171 on 12 June last year, she called her son as she always did before takeoff. The flight was due to leave Sardar Vallabhbhai Patel airport in Ahmedabad, in the western Indian state of Gujarat, and was destined for Gatwick.

“We always had a little traditional thing,” said Patel, a business manager from London. “Once she got on the flight, she would sit down and call me.

She’d tell me: ‘Yep, I’m on the flight. See you later.’” He remembers asking her what she would like for dinner.

“I told her: ‘I’ll be there to come and pick you up. I’ll see you later on.’ That was my last conversation with her.” One year after the crash, bereaved family members say they are still struggling to obtain answers about what happened.

The Boeing 787 Dreamliner struck a medical college shortly after taking off. The crash killed 241 people onboard, including 169 Indian nationals and 52 Britons, as well as 19 people on the ground.