(Bloomberg) -- Southwest Airlines Co. is frustrated by the slow pace of federal certification of Boeing Co.’s smallest 737 Max jet, an issue that could delay the carrier’s commercial debut of the aircraft late into next year.

The concern stems from changes by the U.S. Federal Aviation Administration and lawmakers giving regulators a larger role in the certification, drawing out that process, Southwest executives said in a meeting with Bloomberg News editors and reporters Friday. Previously, Boeing had been allowed to oversee more safety decisions.

“Frustration is the right word,” Chief Executive Officer Gary Kelly said of the delays. “It’s a different regulatory environment. A lot of duties that used to be delegated are vested with the FAA, and they are just getting used to that.”

The FAA doesn’t discuss details of ongoing projects, but it signs off on certification once it’s satisfied standards have been met, the agency said in an emailed statement. Boeing didn’t immediately have a response.

The Max 7, the smallest version of Boeing’s single-aisle workhorse, is a centerpiece of Southwest’s plans to revamp its fleet with newer, more fuel-efficient aircraft. The carrier is the top customer for Max jets, with 660 on order, including more than 230 Max 7 aircraft. The planes are more fuel efficient than the 737-700s they will replace, and have more seats. 

“We do want the 7 and we wanted it yesterday,” Kelly said.

First Quarter

Boeing has told the carrier to expect certification “in the next month, or two or three,” Chief Operating Officer Mike Van de Ven said. “In my mind, I’ve got it sometime in the first quarter.”  

Boeing had earlier indicated the plane would be certified by mid-2021, Van de Ven said. A Boeing executive said last month the company was performing certification activities and expected to deliver the first Max 7 jets in 2022. 

Once the plane is certified, it could take another six months of work at Southwest to ready the aircraft for commercial flights, the Southwest executive said, likely pushing the debut to late 2022.

The changes to the certification process came after a pair of 737 Max 8 crashes that killed 346 people. Subsequent investigations found the FAA needed to delegate fewer decisions to the planemaker and give its own engineers and inspectors more responsibility. Since the crashes, U.S. lawmakers have enacted a variety of new requirements on how the FAA certifies aircraft to bolster the oversight of manufacturers.

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