Boeing Co. withdrew a request for a key safety exemption that would have helped speed approval of its coming 737 Max 7 aircraft, bending to rising pressure to prioritize safety in the wake of a near-catastrophe on one of its planes. 

The concession on the de-icing requirement comes days after Democratic Senator Tammy Duckworth called on the Federal Aviation Administration to reject the company’s petition for a waiver for the yet-to-be certified Max 7.

The US planemaker will instead engineer a solution to address the engine inlet de-icing system during the certification process, Boeing said in a statement late Monday.

“The FAA will determine the timing of certification and we will follow their lead every step of the way,” Boeing said. “We’re committed to being transparent, listening to all our stakeholders and taking action to strengthen safety and quality.”

Boeing’s retreat illustrates just one of the challenges ahead as regulators pore over the company’s manufacturing processes and pressure management to improve the quality of its planes. The setback is likely to extend the time it takes for clearance to start delivering the smallest version of Boeing’s cash-cow narrowbody, putting it at a disadvantage to Airbus SE and Embraer SA.

Senator Tammy Duckworth

Duckworth, who chairs the Senate subcommittee on aviation safety, said in a Jan. 24 letter to FAA Administrator Michael Whitaker that “Boeing forfeited the benefit of the doubt long ago when it comes to trusting its promises about the safety of 737 Max.”

The blowout of a fuselage panel on Alaska Airlines Flight 1282 earlier this month led the FAA to ground Max 9 jets with the door-plug feature. While the stop has since been lifted, Max 9 operators Alaska Air Group Inc. and United Airlines Holdings Inc. have criticized Boeing, as has Southwest Airlines Co., the launch customer for the Max 7. 

Boeing shares have declined 21% this year through Monday, the worst performance among members of the Dow Jones Industrial Average. The stock was off 0.5% in premarket trading as of 7:54 a.m. in New York.

Some analysts now expect further delays to the Max 7, as well as the stretched Max 10 as it follows the smaller plane down the path toward certification. Bloomberg has reported that United is looking for ways to get out of its contract for the biggest Boeing single-aisle and at least partially switch over to Airbus.

The Max 8, the base version of the latest 737, and the Max 9 are both flying with what Duckworth termed the “same anti-ice system defect.” In her letter, she said Boeing won’t be able to implement a fix until 2026. Attempting to put the Max 7 into service before a solution is in place “suggests the company has yet to learn the most basic lesson from its terrible 737 Max history: safety must come before profit,” Duckworth said. 

Southwest said on a conference call last week that its 2024 fleet plans do not include any Max 7 deliveries. 

Chief Executive Officer Robert Jordan said then that he’s spoken with Boeing leadership to make sure “they understand our feelings,” and that the airline supports the planemaker’s efforts to improve.

“The quality issue is a must, improving safety is a must, and becoming a better company is a must,” he said in an interview.