Narrative:

After turn south to intercept 211 degree radial on oasis departure, we were cleared to 7000 ft and then given 8000 ft. Before reaching 8000 ft (first officer flying), both pilots heard controller clear aircraft to 12000 ft. Passing 8500 ft, controller caught climb and said climb wasn't for us and to expedite climb through 9500 ft for traffic. Similar sounding call signs seemed to be the problem. Whether we heard our call sign because we wanted to, or the wrong call sign was given I don't know. We saw traffic visually and on TCASII, never felt in danger. I remember feeling a little uncomfortable with all the traffic I saw on the TCASII and maybe should have questioned ATC. I did repeat call sign and altitude cleared to when given clearance.

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Original NASA ASRS Text

Title: AN ACR FLC FLYING B737 ACCEPTS AND ACKNOWLEDGED CLB CLRNC MEANT FOR ANOTHER ACFT.

Narrative: AFTER TURN S TO INTERCEPT 211 DEG RADIAL ON OASIS DEP, WE WERE CLRED TO 7000 FT AND THEN GIVEN 8000 FT. BEFORE REACHING 8000 FT (FO FLYING), BOTH PLTS HEARD CTLR CLR ACFT TO 12000 FT. PASSING 8500 FT, CTLR CAUGHT CLB AND SAID CLB WASN'T FOR US AND TO EXPEDITE CLB THROUGH 9500 FT FOR TFC. SIMILAR SOUNDING CALL SIGNS SEEMED TO BE THE PROB. WHETHER WE HEARD OUR CALL SIGN BECAUSE WE WANTED TO, OR THE WRONG CALL SIGN WAS GIVEN I DON'T KNOW. WE SAW TFC VISUALLY AND ON TCASII, NEVER FELT IN DANGER. I REMEMBER FEELING A LITTLE UNCOMFORTABLE WITH ALL THE TFC I SAW ON THE TCASII AND MAYBE SHOULD HAVE QUESTIONED ATC. I DID REPEAT CALL SIGN AND ALT CLRED TO WHEN GIVEN CLRNC.

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.