Narrative:

Departed las on the oasys 2 departure with a clearance to maintain 7000 ft. While in the left turn after passing 3 DME, the controller (departure) told us to climb to 8000 ft. We read back the climb clearance and climbed to 8000 ft. While on a southerly heading, eastbound arrival traffic southwest of las vegas airport was passing overhead from right to left at approximately 10000 ft. As we were climbing rapidly, I believe we received a TCASII TA concerning the overhead traffic. At about the same time the departure controller rather excitedly told us to maintain 7000 ft and pointed out the eastbound traffic above us. I reiterated that the controller had cleared me to 8000 ft and that we had read that clearance back. As we were descending back to 7000 ft the controller seemed to admit that she realized that fact. At any rate, separation between aircraft was not less than 2000 ft (I believe) and was continually in sight. I believe the controller merely made a simple error which in this instance did not lead to any problem.

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Original NASA ASRS Text

Title: FLC OF A B737-300 WERE CLBING TO NEWLY ASSIGNED DEP ALT WHEN DEP CTLR ISSUED TA AND INSTRUCTED THEM TO STOP THE CLB AND RETURN TO THEIR ORIGINALLY CLRED ALT.

Narrative: DEPARTED LAS ON THE OASYS 2 DEP WITH A CLRNC TO MAINTAIN 7000 FT. WHILE IN THE L TURN AFTER PASSING 3 DME, THE CTLR (DEP) TOLD US TO CLB TO 8000 FT. WE READ BACK THE CLB CLRNC AND CLBED TO 8000 FT. WHILE ON A SOUTHERLY HEADING, EBOUND ARR TFC SW OF LAS VEGAS ARPT WAS PASSING OVERHEAD FROM R TO L AT APPROX 10000 FT. AS WE WERE CLBING RAPIDLY, I BELIEVE WE RECEIVED A TCASII TA CONCERNING THE OVERHEAD TFC. AT ABOUT THE SAME TIME THE DEP CTLR RATHER EXCITEDLY TOLD US TO MAINTAIN 7000 FT AND POINTED OUT THE EBOUND TFC ABOVE US. I REITERATED THAT THE CTLR HAD CLRED ME TO 8000 FT AND THAT WE HAD READ THAT CLRNC BACK. AS WE WERE DSNDING BACK TO 7000 FT THE CTLR SEEMED TO ADMIT THAT SHE REALIZED THAT FACT. AT ANY RATE, SEPARATION BTWN ACFT WAS NOT LESS THAN 2000 FT (I BELIEVE) AND WAS CONTINUALLY IN SIGHT. I BELIEVE THE CTLR MERELY MADE A SIMPLE ERROR WHICH IN THIS INSTANCE DID NOT LEAD TO ANY PROB.

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.