Washington (AP) - The Federal Aviation Administration said on Friday that Frontier operated about 900 flights without the right signs.
The FAA says that in 2008 and 2009, Frontier reconfigured the cabins on some of its Airbus A318s and A319s so that two aisles could access the emergency exits over the wings, but the signs didn't show the new layout.
The airline has 30 days to respond.
Frontier is based in Denver and is owned by Republic Airways Holdings Inc. In Indianapolis. A republic spokesman did not immediately return a call seeking comment.
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