Can pilots carry guns on commercial flights? Incident on Delta plane raises questions.

A former Delta co-pilot is facing federal charges for allegedly threatening to shoot a flight captain who, during a trip last year, tried to divert their plane because a passenger may have been experiencing a medical emergency in the air, court documents and officials confirmed. 

The former pilot, identified as Jonathan J. Dunn, was indicted by a Utah grand jury on Oct. 18 for allegedly using a dangerous weapon to assault and intimidate an aircraft crew member and interfering with the crew's ability to perform its duties.

New details that came to light this week have raised questions about whether commercial airline pilots are allowed to carry loaded guns aboard a flight, even while regular passengers are not.