The Wall Street Journal is reporting online that United Airlines has temporarily grounded several Boeing 747 jumbo jets to check for compliance with federal maintenance requirements, “in a move that signals the controversy over government oversight of airliner safety checks and repairs is spreading, according to three people familiar with the issue.”

The article goes on to say:

“United’s move, which one person familiar with the matter said covers as many as six long-haul 747 aircraft that had some of their cockpit instruments validated as part of an overseas maintenance check, comes as U.S. airlines are stepping up self-audits of their maintenance compliance. At the same time, the Federal Aviation Administration is launching first-of-a-kind spot checks of compliance with mandatory safety directives at every U.S. carrier.

The FAA ordered the temporary groundings after discovering that test equipment used at a maintenance station in South Korea was faulty, according to one person familiar with the issue.

Re-checking the accuracy of the affected cockpit instruments may only take several hours. But one person familiar with the details said United already has delayed one trans-Atlantic flight from San Francisco by as much as five hours. FAA and United officials couldn’t immediately be reached for comment.

The six affected United aircraft, according to people familiar with the details, all went through major maintenance work at a maintenance facility in South Korea, and FAA inspectors on site noticed that some of the test equipment there wasn’t properly calibrated. It’s unclear how many of the planes flew away from the South Korean facility without having their cockpit instruments verified. It’s also unclear whether other U.S. or foreign airlines may face the same problem.”

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