Boeing CEO Won't Say 737 Max Software Design Was Flawed

"It's not correct to attribute that to any single item," he said. "We know there are some improvements we can make to the MCAS and we will make those improvements. But the reason this industry is safe is that we never stop on making safety improvements. We never claim we have reached the end point. We are continuously, across all of our airplane programs, improving safety every day. We always look for opportunities to improve."

"That culture that's unafraid to make improvements over time, that culture is what has driven this to be an incredibly safe industry," he continued. "That is our commitment; we're not going to waiver from that. We will continually look for opportunities to improve safety. That's our responsibility and that's part of earning that trust back that I talked about earlier."

Safety "for everyone"

One shareholder asked what Boeing was doing to make safety processes more robust. "You don't have to have 300-plus people die every time to find out something is unreliable," the shareholder said.

Muilenburg denied media reports that Boeing may have "rushed the 737 Max to market," saying that "simply is not true. It was a six-year development; 1,600 test-flights of the airplane; 3,700 flight hours of development on the Max, so it was thorough and it was disciplined."

Boeing is first offering standard computer training packages on the new 737 Max software "for everyone" and "then, where it makes sense, augmentation with simulator training," Muilenburg said in response to a question from a retired Air Force lieutenant colonel who also said he owned shares in Southwest Airlines.

CEO has no plans to leave

When a reporter asked him if he'd considered resigning, Muilenburg said he intends to stay, focusing on "safety and quality and integrity."

"I am strongly vested in that my clear intent is to continue to lead on safety and quality and integrity," he said. "It's important to stress that. We deeply regret what happened with these accidents. It gets to the core of our company"

Earlier, a shareholder proposal to remove Muilenburg from his position as chairman of the board failed, with less than 40 percent of shareholders supporting the proposal.

It's far from the first time that question has been posed. On an investor call last week, analysts asked if the outcome of the 737 Max and the ability to restore public trust were key to keeping both roles of chairman and CEO. Muilenburg said he believes in keeping the roles combined.

"I have daily communications with the board, both in my chairman role and in my CEO role," Muilenburg said on the call. "We think that is the right, most effective structure for our company. And I think that's, again, showing it to be the case even in the midst of this challenging situation."

$260 million less revenue

Investment firm Raymond James estimates the 737 Max grounding will reduce revenue at Southwest Airlines, the largest U.S. user with 34 of the jets, by $260 million in the first quarter, while American Airlines will take an estimated $185 million hit in the second quarter.

American Airlines flies 24 of the 737 MAX jets, while United Airlines has 14. Raymond Jones analysts also expect the grounding to result in reduced seating capacity during the summer, which can drive up airfares.

Safety "not optional"

"We don't make safety features optional," Muilenburg said in his prepared remarks. "Safety has been and always will be our top priority, and every one of our airplanes includes all of the safety features necessary for safe flight."

4 whistleblower calls

Earlier on Monday, CBS News confirmed that the Federal Aviation Administration has received at least four calls from potential Boeing employee whistleblowers about issues with the company's new 737 Max jetliner.