Narrative:

Climbing through approximately FL280 to the altitude we were cleared to; FL300; we received a TCAS RA. TCAS said 'descend; descend;' so I disengaged the autopilot and initiated descent into green band on V/south. Almost immediately; TCAS changed command to 'climb; climb' so I reversed direction and climbed into the green band until we were clear of traffic. We were IMC. ATC seemed busy and presumably didn't realize they had cleared us to climb through someone else's altitude.

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Original NASA ASRS Text

Title: Air carrier flight crew reported receiving an RA after ATC cleared them to climb to another aircrafts altitude.

Narrative: Climbing through approximately FL280 to the altitude we were cleared to; FL300; we received a TCAS RA. TCAS said 'descend; descend;' so I disengaged the autopilot and initiated descent into green band on V/S. Almost immediately; TCAS changed command to 'climb; climb' so I reversed direction and climbed into the green band until we were clear of traffic. We were IMC. ATC seemed busy and presumably didn't realize they had cleared us to climb through someone else's altitude.

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.