Narrative:

I was made aware by the controlling dispatcher of a flight number conflict. Flight xyz was still airborne and flight number active when XYZ1 took off. This created a conflict with the local ATC facilities. I subsequently saw an ACARS message from the outbound crew alerting dispatch to the conflict.

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Original NASA ASRS Text

Title: Dispatcher learns that two aircraft are airborne with the same flight number causing confusion for ATC.

Narrative: I was made aware by the Controlling Dispatcher of a flight number conflict. Flight XYZ was still airborne and flight number active when XYZ1 took off. This created a conflict with the local ATC facilities. I subsequently saw an ACARS message from the outbound crew alerting Dispatch to the conflict.

Data retrieved from NASA's ASRS site as of April 2012 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.