Tom Wagner was on his way to California when he managed to sleep through the landing, the disembarking, and the post-flight cabin inspection (though no one quite knows how), waking up locked in a dark airplane completely alone, reports Steve Almasy at CNN.

Tom Wagner Airplane

“I was coming from Louisiana to see my sister in California. We had a layover in Texas,” said Wagner. “I just took my hat off and I took a nap…What if I had a medical condition or something? What if I had a heart attack and I was dead?”

Crew failed at (or skipped) post-flight inspection

Wagner called his girlfriend, and after he convinced her that it wasn’t a joke she called United Airlines so that they could let him out of the plane. United put Wagner up in a hotel and gave him a $250 voucher, but they’re at a loss to explain how the cabin crew failed to realize that someone was still on the plane when they left and locked up.

“ExpressJet is investigating to determine how this occurred. We sincerely apologize for the inconvenience this caused for the passenger,” the company said in a statement. ExpressJet says that a post-cabin inspection was conducted as required, so either the cabin crew needs a bit of re-training or the inspection of a short, small flight was skipped with the thought that no one would notice.

United also subject of DoT fines for tarmac delays

Ironically, United was recently fined $1.1 million by the Department of Transportation for making passengers wait on the tarmac. There is supposed to be a three-hour limit before passengers are returned to the terminal, but United violated this rule during a severe thunderstorm on July 13, 2012, holding 13 planes for longer than the stated limit, with the violations ranging from just a few minutes to more than four hours. This is the largest penalty ever levied for violating the tarmac rule, and a sign that the rule may be more stringently enforced in the future. The maximum fine for holding passengers too long is $27,500 per person.

Of course, Wagner’s case is a different matter, but no one should be surprised if he gets a lawyer and asks for a great deal more than $250.