Narrative:

Flight msp-phl was on the msp 5 departure. As the aircraft was climbing through 6200 ft to the prescribed 7000 ft, departure control directed the crew to level off at 6000 ft, due to a potential traffic conflict. The flying copilot returned to 6000 ft as the non flying captain acquired the traffic visually. The flight was then cleared to a higher altitude. ATC believed the flight had been assigned 5000 ft but this clearance was not received by the crew.

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Original NASA ASRS Text

Title: FK10 ALTDEV ALT OVERSHOT. CLBING TFC. POTENTIAL CONFLICT LTSS.

Narrative: FLT MSP-PHL WAS ON THE MSP 5 DEP. AS THE ACFT WAS CLBING THROUGH 6200 FT TO THE PRESCRIBED 7000 FT, DEP CTL DIRECTED THE CREW TO LEVEL OFF AT 6000 FT, DUE TO A POTENTIAL TFC CONFLICT. THE FLYING COPLT RETURNED TO 6000 FT AS THE NON FLYING CAPT ACQUIRED THE TFC VISUALLY. THE FLT WAS THEN CLRED TO A HIGHER ALT. ATC BELIEVED THE FLT HAD BEEN ASSIGNED 5000 FT BUT THIS CLRNC WAS NOT RECEIVED BY THE CREW.

Data retrieved from NASA's ASRS site as of July 2007 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.