Narrative:

Flight 1928 and flight 1988 are in the spa/GA high sector again at the same time. We've been through this for two years now. These two aircraft were involved in one of the worst losses of separation for some time. They routinely take each others' clearances and controllers routinely confuse the call signs. A controller may not notice these aircraft on frequency and potentially could give a clearance to the wrong one. It has happened before especially when they are on separate frequencies that are paired at the combined sector. One on GA high's frequency (en route) and one climbing off atl on the spa high frequency. These call signs were changed at some point last year but here they are again in the system. Get the call signs changed before another extremely dangerous situation occurs.

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Original NASA ASRS Text

Title: A ZTL Controller contends that the similar flight numbers used by one airline are extremely dangerous.

Narrative: Flight 1928 and Flight 1988 are in the SPA/GA High Sector again at the same time. We've been through this for two years now. These two aircraft were involved in one of the worst losses of separation for some time. They routinely take each others' clearances and controllers routinely confuse the call signs. A Controller may not notice these aircraft on frequency and potentially could give a clearance to the wrong one. It has happened before especially when they are on separate frequencies that are paired at the combined sector. One on GA High's frequency (en route) and one climbing off ATL on the SPA High frequency. These call signs were changed at some point last year but here they are again in the system. Get the call signs changed before another extremely dangerous situation occurs.

Data retrieved from NASA's ASRS site as of July 2013 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.