WASHINGTON - Federal Aviation Administration officials and Southwest Airlines leaders likely will be scolded by U.S. Rep. Jim Oberstar during a hearing Thursday for what Oberstar views as their breach of public safety.

The FAA has levied a $10.2 million fine against Southwest for flying 46 airplanes that should have been taken out of service for fuselage inspections.

But Oberstar said during a press briefing Tuesday that his committee has gathered evidence that FAA personnel have knowingly allowed planes to be flown beyond required inspection deadlines.

Oberstar, D-Minn., chairman of the House Transportation and Infrastructure Committee, has called the oversight hearing because he is disturbed by what he characterizes as FAA "complacency." He argues that instead of rigorously enforcing standards to keep passengers safe, some officials within the FAA have chosen to develop "cozy" relationships with the airlines.

FAA officials and inspectors as well as Southwest CEO Gary Kelly are scheduled to appear before Oberstar's committee.

In advance of Oberstar's investigative hearing, in which he plans to reveal critical lapses in FAA oversight, the federal agency issued a national order to its flight standards offices on March 13. In recent weeks, the FAA has paid special attention to compliance with airworthiness directives. Some carriers -- including American Airlines -- have grounded aircraft for inspections.

Speaking to reporters about the accelerated FAA activity, Oberstar said: "Do you think that would have happened if we had not been hot on the trail?"

Nobody from Eagan-based Northwest Airlines is on the list of those to testify at the hearing Thursday.

Ken Hylander, chief safety officer at Northwest, said in a statement Tuesday that "we make safety Topic No. 1 at all levels of the organization."

Hylander noted that Northwest's board has a safety committee, and that the importance of operating a safe airline is emphasized from the moment a Northwest employee joins the airline.

Shortly after the Northwest mechanics' strike began in August 2005, an FAA inspector alleged that Northwest's replacement workers were not properly trained. In a September 2007 report, the inspector general's office in the Department of Transportation found that the FAA needed better procedures for investigating and resolving inspector safety concerns.

Since the mechanics' strike, the majority of Northwest's maintenance work has been performed by third-party vendors.

"We have direct oversight of our maintenance whether it is done in-house or outside," Kris Bauer, Northwest's senior vice president of technical operations, said in a statement Tuesday.

In Northwest's large Twin Cities and Detroit hubs, Northwest mechanics do daily line-maintenance work. In its smaller Memphis hub and in spoke stations around the United States, outside vendors do the maintenance work, overseen by Northwest managers.

When extensive, regularly scheduled work is done on airplanes, it is called heavy maintenance. At heavy-maintenance vendor sites, Bauer said, "We have people out there permanently looking at every airplane."

He stressed that whether the work is done by Northwest mechanics or outside vendors, the maintenance program has "the same standards."

Bill Swelbar, who analyzes airline data at the Massachusetts Institute of Technology, noted that Northwest spent about 72 percent of its maintenance budget in 2006 on outside vendors. Swelbar said he's seen no correlation between the level of outsourcing and degree of compliance with FAA safety regulations.

He added that Northwest and other airline executives know that "first and foremost they are selling safe travel."

Bauer said some of Northwest's maintenance vendors are the original manufacturers of the equipment. The airline contracts with Pratt & Whitney to maintain engines on Boeing 747s and 757s and Airbus A330s. ST Aero is Northwest's largest provider for maintaining Northwest's airframes, and it has facilities in Alabama, Texas and Singapore.

Oberstar emphasized that the FAA and the airlines both must be vigilant in enforcing safety standards. "We know that the FAA does not have sufficient personnel, even if they had 50,000 maintenance inspectors," Oberstar said.

In addition to federal regulators, he said, "Safety in aviation relies on a corporate culture of safety."

Liz Fedor • lfedor@startribune.com • 612-673-7709