WASHINGTON — Government inspections to uncover serious maintenance problems that could cause airline crashes are often delayed for years or miss the biggest risks, according to a government watchdog.

In a report being circulated among key congressional committee members, the Department of Transportation’s inspector general identified several weaknesses that undermine a key Federal Aviation Administration airline maintenance oversight program. Unless FAA fixes those weaknesses, the report said, its ability to “effectively oversee the National Airspace System” is lessened.

The Associated Press obtained a copy of the report today.