Boeing’s chief executive, Dennis A. Muilenburg, will acknowledge some of the company’s failings on Tuesday when he appears before a Senate committee investigating the crashes of two 737 Max jets that killed 346 people.

“We know we made mistakes and got some things wrong,” Mr. Muilenburg plans to tell the lawmakers, according to Boeing. “We own that, and we are fixing them.”

Mr. Muilenburg has made similar comments in speeches but his appearances this week will be the first time Boeing executives have publicly addressed Congress about the crashes, which have cost the company billions of dollars and raised new questions about government oversight of the aviation industry.

Mr. Muilenburg will face the Senate on the first anniversary of the crash of Lion Air Flight 610, which was the first Max to crash. On Wednesday, he will appear in front of a House committee.