Antonis Mavropoulos says he feels a moral obligation to the 157 killed to find out why the Ethiopian Airlines plane crashed

Antonis Mavropoulos knows he is lucky. Alone among passengers booked on to Ethiopian Airlines flight ET302, he got to the departure gate two minutes after it had closed. “I could see a guy in a green T-shirt and others boarding and I shouted to also be let in,” he says, his voice cracking with emotion. “I am still in a state of shock knowing what happened. I’ve found it very difficult to sleep since.”

Five days after the Nairobi-bound Boeing 737 Max 8 jet crashed within minutes of takeoff from Addis Ababa, the Greek chemical engineer says he feels he has a moral obligation to uncover why the plane went down, killing all 157 people onboard.

“As the guy who was saved just by luck I want to say something very clear,” he says. “The souls of these people, the people who I saw and all those who died, can never be relieved unless there are concrete answers and the truth is uncovered.”

The latest news alluding to design faults had especially unsettled him. “I have been reading a lot of reports about potential problematic designs, that the pilot asked soon after takeoff to go back, and to be honest it has freaked me out. I fly between 100 and 120 times a year. I very much hope this is not a case of criminal ignorance or of design issues being intentionally hidden,” he tells the Guardian during a phone interview from Beirut where he works much of the time as the head of an Athens-based waste management company.

The 53-year old, who also presides over the International Solid Waste Association, an NGO headquartered in Vienna, was on his way to Nairobi via Addis Abada last weekend to attend the UN environment assembly. Travelling from Beirut overnight, he was aware that his stopover was so short that he would have to make a run for it as soon as he landed.

“I am not the sort of person who travels business, but in this case I did because the next flight left 30 minutes later and I thought it would have some leverage in my being able to make it. I was the first to get off the plane and was told a connection ambassador would be on the ground to escort me, but in the event he was delayed by a couple of minutes. That, and the fact that I was carrying my own luggage were the two things that saved me. If I had checked it in, the gate wouldn’t have closed and the flight would have waited.”

When he was told he would have to take the next flight three hours later, Mavropoulos was initially irritated.

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Waiting in the lounge, without access to the internet or TV, he did not find out what had happened to flight ET302 until much later. “I don’t know if it applied to the whole airport, but no one could get online and it was only as I was going to board the [second] flight at around 10.50am that one of the women said our manager wants to speak to you. It’s a matter of protocol, as you are the only passenger who did not board the earlier plane that went missing.”

It was only then, and when he subsequently received a text from a friend in Athens relaying the news of the crash in detail, that reality began to dawn. “I realised how close it was and how randomly I was saved, and at the same time I was like imploding inside because it was just way too much,” he says. “Even if I was saved it was also a huge burden in my mind, knowing what had happened to everyone else. I felt the ground slipping away from under my feet. I knew instantly that I had to call my family, my mother, wife and daughter, the people I love, to relieve them of the burden of worrying.”

Play Video 1:34 Ethiopia plane crash: what we know about the disaster so far – video

Mavropoulos eventually flew to Nairobi later that day and attended the UN environment assembly. He kept himself busy meeting people, listening to lectures and giving talks.

Since then he has also spent a great deal of time contemplating the role of chance in a person’s life. “I know we Greeks are given to philosophising, but I have spent a lot of time in recent days thinking how important randomness is in our daily lives and how we should respect it more than we do.

“Often we speak about bad luck but we don’t so often acknowledge good luck and the integral part it plays in our lives … It might be the case that the only reason I was saved is to help uncover why everyone else on that plane died.”