YUMA, Ariz. — Three more Southwest Airlines jetliners have small, subsurface cracks that are similar to the cracks suspected of playing a role in the fuselage tear of a Boeing 737-300, causing the aircraft to lose pressure and forcing a frightening emergency landing, officials say.
The 5-foot-long hole tore open in the passenger cabin roof area shortly after the plane left Phoenix for Sacramento, Calif., Friday afternoon. None of the 118 people aboard was seriously hurt as the plane descended from 34,400 feet to a military base in Yuma, 150 miles southwest of Phoenix.
Since then Southwest grounded its 79 other Boeing 737-300s and began inspecting them.
The airline said in a statement Sunday that two planes have been found to cracks similar to those in the stricken aircraft and will be evaluated and repaired before they are returned to service. A National Transportation Safety Board member told The Associated Press later that a third plane had been found with cracks developing.
The other 19 aircraft inspected so far showed no problems and will be returned to service.
Checks on the remaining jets are expected to be completed by late Tuesday, the airline said. That means flight cancelations will likely continue until the planes are back in the air. About 600 flights in all were canceled over the weekend after Southwest grounded 79 of its planes.
The cracks found in the three planes developed in two lines of riveted joints that run the length of the aircraft. The agency is focusing its probe on the area of the cracks but has not determined that the cracks caused the rupture.
NTSB board member Robert Sumwalt said Boeing was developing a "service bulletin" for all 737-300 models with comparable flight cycle time as the Arizona jet, which was 15 years old and had about 39,000 takeoff and landing cycles.
There are 931 such models in service worldwide, 288 of which in the U.S. fleet.