Fuselage cracks: Is the problem with Southwest Airlines or Boeing 737s?
The FAA called Monday for inspections of older Boeing 737s, after an incident on Friday in which the roof tore off Southwest Airlines Flight 812.
(Page 2 of 2)
The FAA said its new directive will require inspections using electromagnetic technology in specific areas of the aircraft fuselage, on certain 737s that have been through more than 30,000 flight cycles. It will then require repeat inspections at regular intervals.Skip to next paragraph
Subscribe Today to the Monitor
A significant regimen of fuselage testing has been in place for 737s, in particular, since an Aloha Airlines 737-200 ripped open during a 1988 flight, says Mr. Voss, who is president of the Flight Safety Foundation, a nonprofit group focusing on aviation safety issues. The plane landed safely but one flight attendant died during the incident.
In Friday's incident, the cabin depressurized and a sizable hole opened in the roof of the plane, prompting an emergency landing at an Arizona military base. Passengers said they could see blue sky through the roof of Flight 812, bound for Sacramento, Calif.
Aircraft in general are inspected with greater care as they age. Each takeoff and landing puts stress on a plane, due to the changes in cabin pressure as the plane ascends and descends. When so-called "fatigue cracks" are found, the planes are routinely repaired. The plane involved in Friday's incident was 15 years old, according to FAA records. On average, Southwest's fleet of 548 planes is 11 years old, each flying about six flights per day.
Voss says that Southwest accounts for most of the "high-cycle" 737s operating in the US. Those are planes that, like the one on the Phoenix flight, have been through as many as 39,000 takeoff and landing cycles.
Southwest has had problems with fuselages tearing in the past. In 2009, a foot-long hole opened in the top of a jet, forcing an emergency landing in West Virginia. That same year, the airline was fined $7.5 million by the FAA for nearly 60,000 flights in which the planes had not undergone required inspections for fuselage cracks.
Cracks caused by structural fatigue can be invisible to the eye. The current inspection of Southwest airplanes, aided by personnel from Boeing, uses a low-frequency current to analyze the aircraft skin for weakness.
Southwest cancelled a number of flights over the weekend, but said Monday it was operating all but about 70 of its 3,400 scheduled departures. The National Transportation Safety Board is investigating what happened on Southwest Flight 812.
Material from wire services was included in this story.
IN PICTURES: The wide world of air travel