Posted on: 04 April 2011 by Mark Howells
Southwest Airlines is working with the US National Transportation Safety Board (NTSB) to determine the cause of a depressurisation event – which left a hole in the fuselage – during a Phoenix–Sacramento flight on 1 April that diverted to Yuma, Arizona, where it completed a successful emergency landing.
In co-operation with Boeing, an additional inspection programme has been set up for a subset of Southwest’s 737-300s. The inspection involved a non-destructive test (NDT) in the form of high-frequency Eddy current of the aircraft skin. This test is designed to detect any subsurface fatigue in the skin that is not visible to the eye.
Inspections of the sub-fleet (79 total) are ongoing. As inspections are completed with no findings, those aircraft will continue be put back into service. The airline anticipates completing the inspections by late Tuesday 5 April. The 79 aircraft designated for the additional inspections were designed differently in the manufacturing process.
On Sunday 3 April, Southwest cancelled approximately 300 flights as the inspections began.
"I could not be more proud of our maintenance and engineering professionals who supported Boeing and the FAA in the establishment of these new inspection procedures," remarked Mike Van de Ven, Southwest’s executive vice-president and chief operating officer. "Boeing has since identified an inspection programme for this section of the aircraft. Based on this incident and the additional findings, we expect further action from Boeing and the FAA for operators of the 737-300 fleet worldwide.
"Our highest priority is the safety of our employees and customers," Van de Ven added. "Prior to the event regarding Flight 812, we were in compliance with the FAA-mandated and Boeing-recommended structural inspection requirements for that aircraft. What we saw with Flight 812 was a new and unknown issue. We regret any customer inconveniences as a result of the inspections currently underway. Delays and cancelations are never the preference, however we are taking every precaution we can to ensure that our operation is safe."