The Federal Aviation Administration (FAA) has proposed a hefty fine against Horizon Air for allegedly flying almost two dozen airplanes that were not in compliance with federal regulations.
Horizon Air faces a potential civil penalty of $1,005,000. FAA alleges the Seattle-based airline used blind rivets on the installation of new security flight deck doors, instead of the required solid rivets.
The FAA claims the airline flew the 22 non-compliant Bombardier DHC-8-402 turboprop airliners on 186,189 flights. Even after being told that these Horizon planes didn't meet federal requirements, the airline reportedly operated one of the planes on another passenger-carrying flight before replacing the rivets.
Installing these blind rivets could damage components like wiring, the FAA said.
"We expect airlines to comply with all of our safety regulations and to correct safety defects promptly," said U.S. Transportation Secretary Ray LaHood.
Horizon's alleged violations were discovered when their 23rd incorrectly-modified plane experienced an in-flight wiring damage incident on a non-revenue flight.
Horizon has 30 days to respond to the FAA. The agency sent a letter dated Aug. 1 to Horizon Air president Glen Johnson detailing a report of their investigation.
The regional airline is a subsidiary of Alaska Air Group, which also owns Alaska Airlines. The company did not immediately return NBC News' request for comment.
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