The conference calls, which lasted about 30 minutes each and were held over three days last week, are part of Boeing’s attempts to win back the trust of airlines, which have lost billions of dollars and had to cancel thousands of flights because of the Max grounding. The effort was led by Bernard Choi, a member of the company’s communications team.

Some United States airline executives bristled at the presentation and materials, according to four people familiar with the matter, believing that Boeing has lost credibility and that the company’s involvement would only hurt their efforts to win back the trust of passengers. But dozens of airlines around the world have ordered the Max, and many of them, especially the smaller ones, could find the materials helpful.

“We routinely engage with our airline customers’ communications teams to seek their feedback and brief them on our latest plans,” Gordon Johndroe, a Boeing spokesman, said in a statement on Monday. “Each airline is different in their needs, so we provide a wide range of documents and assistance that they can choose to use or tailor as they see fit.”

Boeing has faltered badly in its public response to the crashes. The ousted chief executive, Dennis A. Muilenburg, who was fired Monday, repeatedly made overly optimistic projections about when the Max might return to service, upsetting regulators and airlines. He drew the ire of lawmakers at congressional hearings, where the families of crash victims winced at his name. The hiring of the top crisis communications firms Sard Verbinnen and Edelman did little to improve the company’s reputation.