FORT WORTH, Texas — With the Boeing 737 Max aircraft grounded by President Donald Trump’s emergency order, in the wake of two overseas crashes that apparently occurred under near-identical circumstances involving the aircraft’s anti-stall sensors, major questions and concerns about the design of the 737 Max remain.

“My instinct is the flying public is not going to embrace the Max 8 without a Herculean and highly transparent effort, not only by Boeing, but also regulators, to ensure its safety,” said Mike Slack, an aviation attorney and a former NASA aerospace engineer. “I don’t know if that bar is attainable. I think the Max 8 may go onto that pile of airplanes damaged by reputation.”

Boeing officials have pledged to correct the erroneous activation of the maneuvering characteristics augmentation system, which is believed to be a factor in the Oct. 29 crash of a Lion Air Flight 610 into the Indonesia seas that killed 189 people, as well as the March 10 crash of an Ethiopian Airlines Flight 302 that killed 157 people.

“We have the responsibility to eliminate this risk, and we know how to do it,” Dennis Muilenburg, Boeing chief executive officer, said in a statement this month. “Safety is our responsibility, and we own it. When the MAX returns to the skies, we’ve promised our airline customers and their passengers and crews that it will be as safe as any airplane ever to fly.”

Fort Worth-based American Airlines and Dallas-based Southwest Airlines continue to cancel roughly 150 flights a day, as their 737 Max aircraft — 58 planes between the two corporations — remain idle. American bought 24 of the 737 Max aircraft, and Southwest owns 34 of the planes. The cancellations are costing both airlines millions of dollars.

American has extended its cancellation of 737 Max flights until June 5, and Southwest announced Thursday it has canceled its 737 Max flights through Aug. 5, meaning both airlines are likely to still be dealing with the prickly issue well into the summer travel season.

Pilots say they’re ready

But American Airlines pilots say that once the 737 Max is cleared for takeoff, they will have no qualms about stepping into the cockpit. Dennis Tajer, spokesman for the Fort Worth-based Allied Pilots Association, which represents 15,000 American Airlines pilots, pointed out that the American version of the 737 Max are built with two “angle of attack” displays that provide an extra layer of protection in the event a sensor malfunction.

“The pilots for the world’s largest airline have the necessary training and experience to troubleshoot problems and take decisive actions on the flight deck to protect our passengers and crew,” Tajer said in a statement released after the Ethiopia crash.

But Slack said the Federal Aviation Administration, which was criticized for being among the last aviation safety agencies in the world to ground the Boeing aircraft, should question why the 737 Max needs to have an automatic pitch correction system. A plane designed from the ground up wouldn’t need such a behind-the-scenes protective measure built into its electronics, he said.

Some critics say Boeing may have acted hastily in increasing the size of the engines and moving them further forward on the 737 Max models, a move that made the planes more fuel-efficient but also changed weight distribution.

“One of the problems we have with the system is, why put a system like that on an airplane in the first place?” Slack said. “… It is within the realm of possibility that, if much of the basic pitch stability performance of the plane cannot be addressed by a software fix, a redesign may be required and the Max might not ever fly,” Slack said.

Winning back trust

Even if the 737 Max is certified again as airworthy, Boeing will have to work hard to win back the public’s trust, said Brian Richardson, who teaches graduate level crisis communication courses at the University of North Texas.

“Right now, the narrative is that this is an unsafe plane. Boeing has to create a new narrative, and not a narrative built on spin,” Richardson said. “I’m going to need to see it with my own eyes — what did they do to correct the problem? And, I’m going to need to see comment from aviation experts saying, ‘Yes. I agree with that.’”