SAN FRANCISCO, Oct. 28 (Xinhua) -- Boeing CEO Dennis Muilenburg is set to testify in front of the U.S. House and Senate committees this week about its 737 Max planes involved in two deadly air crashes that killed 346 people, the company has said.

"We know we made mistakes and got some things wrong," Muilenburg said in an opening statement on Monday. He will appear before the Senate Commerce committee on Tuesday and the House Transportation committee on Wednesday.

The largest aircraft manufacturer in the United States said it has made robust improvements to the 737 Max flight control software, which was partially blamed for fatal crashes of Indonesian Lion Air Flight 610 in October 2018 and Ethiopian Airlines Flight 302 in March, killing 346 passengers and crew.

At the hearings, Muilenburg will describe efforts to improve the performance of 737 Max, the company's newest plane, and prevent future accidents.

Boeing's 737 Max jets have been grounded across the globe since March following more evidence that its key flight control software played a part in the two deadly crashes in five months.