On Mar. 13, Southwest Airlines returned to service 34 of 38 737 Classics it temporarily grounded on Mar. 12 for inspection and operated a normal schedule, saying the other four aircraft will need "surface repairs" expected to be completed by this weekend.

Meanwhile, CEO Gary Kelly met with FAA Acting Administrator Bobby Sturgell and other agency officials on Mar. 12 to brief the regulators on measures SWA is taking to avoid maintenance inspection problems such as those that led to a proposed US$10.2 million civil penalty and this week's temporary grounding.

The airline and FAA are expected to undergo tough questioning at an Apr. 3 House of Representatives Transportation and Infrastructure Committee hearing. Chairman James Oberstar (D-Minn.) said this week's "action by Southwest Airlines raises serious questions about whether FAA adequately followed up on the discovery a year ago that Southwest had failed to make required inspections."

A pair of "whistle-blower" FAA inspectors are expected to testify that the agency's former SWA safety supervisor knowingly allowed the carrier to operate improperly inspected aircraft and generally was too "cozy" with the airline to regulate it objectively. Oberstar also claims to have damaging information about other FAA safety oversight abuses.