The widow of an Irish man who died in an Ethiopian Airlines crash two years ago has said she and other families just want justice for their loved ones.

Mick Ryan, from Lahinch in Co Clare, was one of 157 people who died when the Boeing 737 Max crashed minutes after take off en route from Addis Ababa in Ethiopia to Nairobi in Kenya on 10 March 2019.

The father-of-two was part of an engineering unit with the United Nations World Food Programme.

His widow, Naoise Connolly Ryan, is pursuing a civil case against Boeing in the US.

Speaking on RTÉ's Today with Claire Byrne, she said she wants to know "what they knew, who knew what, and when" after a similar crash five months before the Ethiopian Airlines incident.

In that instance, 189 people were killed when a flight from Indonesia crashed minutes after the plane took off.

In both cases, the crashes were associated with a software failure known as Maneuvering Characteristics Augmentation System (MCAS).

Ms Connolly Ryan said they found out afterwards from reports and testimonies that when the first crash was investigated, the Federal Aviation Administration (FAA) had predicted a further 15 crashes would happen specifically due to the MCAS during the lifetime of these planes.

If Boeing was using the plane for American Airlines, for example, it had two sensors, but if they were selling it overseas to the rest of the world, they gave an option as to whether they wanted two sensors or one, something Ms Connolly Ryan believes is critical.

"It just seems insane that something that was a matter of safety ... that they would give an option for these sensors," she said.

"A minimum of two sensors installed is standard. These sensors are like little weather vanes ... that's what sends the information to the MCAS. If they're faulty, they send incorrect information and MCAS kicks in and takes over the plane, so the pilots have no control."

Boeing was fined $2.5bn in January by the US Justice Department and the Boeing Max has since returned to service.

"Nobody has been held to account," Ms Connolly Ryan said.

In an 18-month US Congressional investigation families of crash victims were mentioned but never consulted. She said the families want to know what was learned after the first crash.

"We want to know what they knew, who knew what, and when", she said, adding that there cannot be real change or a guarantee that passenger safety will come first unless there is accountability and justice.

Ms Connolly Ryan said this has taken up a lot of her time, but "you can't put a price on this". She said she has to "go after the truth", while at the same time coping with the loss of her husband, her best friend.

"The only way I can really deal with it is by kind of going in and out of it," she said.

"There are times where I need to be quite immersed in it and there are times when I just need to switch off, and at those times I have support from family and friends around me".

She said it is not something you move on from, but rather something you "move through".

"Our lives have been completely turned upside down", she said. "All the dreams that we had as a family have turned into an absolute nightmare.

"The last two years have been incredibly difficult for all of us, but the support of family and friends has really helped us through, and I just try and keep focused on what Mick would want for us and to somehow keep moving forward.

"I really do draw my strength from Mick. He brought so much joy to our lives and I try and tap into that joy whenever and wherever I can."

Mr Ryan was honoured by the Irish Red Cross recently, which Ms Connolly Ryan said was "incredible". She said he would have been very humbled by the award and they are "incredibly proud of him".

"He was a humanitarian in every sense of the word."