The CEO of Boeing apologized Wednesday to the families of those who died in recent 737 Max jet crashes, saying he feels terrible about the deaths on board the since-grounded plane model.

Dennis Muilenburg, the CEO of the beleaguered aircraft manufacturer, made the apology in a sit-down interview with CBS News .

I do personally apologize to the families, he said. As Ive mentioned earlier, we feel terrible about these accidents, and we apologize for what happened. We are sorry for the loss of lives in both accidents.

Two 737 Max jet crashes a Lion Air flight in October and an Ethiopian Airlines flight in March both killed all people on board, totaling 346 fatalities.

We are sorry for the impact to the families and the loved ones that are behind, and that will never change. That will always be with us. I can tell you it affects me directly as a leader of this company. Its very difficult.

Though the U.S. issued an emergency order grounding all models of the plane in March, it wasnt until earlier this month that Boeing acknowledged there were design flaws in the flight simulator training software connected to both crashes.

Boeing is now working with the Federal Aviation Administration again to determine what kind of training is needed for 737 Max pilots and hopes to have the planes back in the air this coming fall.

We cant change what has happened in these accidents but we can be absolutely resolute in what were going to do on safety going forward, Muilenburg told CBS. So I am sorry for that. We apologize to the families that have been affected. We apologize more broadly to the traveling public where confidence has been affected.