Narrative:

The [duty manager] allowed two flights with the same flight numbers to launch and be in the air at the same time. We were notified of this; and subsequently changed [one of the flight numbers] to a flight number that should have been given to the aircraft in the first place (prior to launch).preventative measures: possibly give the [duty manager] some type of automation tool that would bring to their attention that two flights with the same flight number have the potential for being in the air at the same time.

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Original NASA ASRS Text

Title: Air carrier Dispatcher reported discovering there were two Company flights with the same flight number in the air at the same time.

Narrative: The [Duty Manager] allowed two flights with the same flight numbers to launch and be in the air at the same time. We were notified of this; and subsequently changed [one of the flight numbers] to a flight number that should have been given to the aircraft in the first place (prior to launch).Preventative Measures: Possibly give the [Duty Manager] some type of automation tool that would bring to their attention that two flights with the same flight number have the potential for being in the air at the same time.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.