The FAA has confirmed it is considering penalising Southwest Airlines $12m for a series of failings related to the maintenance of its fleet of 737s.
The regulator has outlined three enforcement cases, two of which relate to work carried out by MRO firm Aviation Technical Services (ATS).
In 2006 Southwest began so-called “extreme makeover” alterations to eliminate potential cracking of the aluminium skin on 44 aircraft. An FAA investigation has concluded that ATS failed to follow proper procedures for replacing the fuselage skins.
ATS workers did not, for example, follow required procedures for stabilising the 737s while replacing the skins. Such actions can result in an airframe shifting and lead to subsequent problems with the new skin.
Also, following the application of sealant beneath the new skin, ATS staff failed to install fasteners in all of the rivet holes during the correct time period for the sealant to be effective. “This could have resulted in gaps between the skin and the surface to which it was being mounted. Such gaps could allow moisture to penetrate the skin and lead to corrosion,” warned the FAA.
Meanwhile Southwest Airlines, which was ultimately responsible for ensuring that the correct procedures were followed, failed to do so, according to the FAA.
The regional carrier then returned the 737s to service and operated them on numerous flights when they were not in compliance with airworthiness directives. The FAA did later approve the repairs after the airline provided proper documentation that the repairs met safety standards.
In the third enforcement case against Southwest, the FAA alleges that the carrier failed to properly install ground wires on water drain masts on two of its Boeing 737s in response to an FAA Airworthiness Directive addressing lightning strikes.
The FAA alleges that the aircraft were flown on at least 20 passenger flights in breach of regulations before they were rectified, despite Southwest knowing of the issue.
“The FAA views maintenance very seriously, and it will not hesitate to take action against companies that fail to follow regulations,” said FAA administrator Michael Huerta.
Southwest now has 30 days to respond the regulator’s allegations.