Boeing recommends inspection of hundreds more of its 737s aircraft

Boeing recommended inspections of hundreds more of its 737 aircraft after a crippled Southwest Airlines plane was forced to make an emergency landing last week.

The Federal Aviation Administration (FAA) ordered airlines to inspect about 175 older Boeing 737s that have had more than 30,000 takeoffs and landings.

Paul Richter, Boeing’s chief engineer for the family of 737 planes, said the 175 737-300s, 400s and 500s targeted by the FAA for inspection had entered service between 1993 and 2000.

The planes are found “pretty much all over the world” and inspections likely would be completed within five days, said Mr Richter in a conference call, without identifying the carriers involved.

Mr Richter said the company had expected cracks to develop along a lap joint, but normally that would occur much later than the 30,000 flight cycle threshold set by the FAA.

“Our plan previous to this event was to recommend inspection at 60,000... which we felt was a very conservative number,” he said.

Mr Richter said there were 570 other planes that would soon reach the 30,000 number for takeoffs and landings and they should also be on the inspection list.

And because of the issue with the lap joints, where two pieces of material overlap, inspections should occur after every 500 flights, he said. The inspection of a single plane takes about eight hours, he added.

By contrast, the FAA directive does not require repetitive inspections at regular intervals. Mr Richter said he was confident in the performance of Boeing’s latest 737, the Next-Generation 737, in which the lap joint design was “a significant improvement” over the previous design.

The US aerospace giant also suggested that Southwest’s operations of its all-737 fleet were not to blame for the incident.

“It’s just a statistical event more than anything to do with Southwest and how they operate,” Mr Richter said, pointing out that the popular budget airline “has one of the largest fleets of 737s in the world”.

The medium-haul twin-engine 737, largely used for regional and national flights, is the world’s best-selling plane.

Southwest said it was resuming normal flight operations and had found cracks on five of the 79 Boeing 737-300 aircraft it had voluntarily grounded after the incident.

“Minor subsurface cracking was found in five aircraft that will remain out of service until Boeing recommends appropriate repairs and those repairs have been completed,” Southwest said.

Southwest Flight 812 made an emergency landing in Arizona on Friday after a hole opened in the roof of the 737-300, causing a rapid loss of loss of cabin pressure.

Southwest pulled 79 Boeing 737-300s out of service, cancelling hundreds of flights for three days to inspect them for “skin fatigue”.

“With our knowledge of what the FAA had planned, we believe the 79 aircraft identified for inspection will accomplish this directive for Southwest Airlines.”