Narrative:

Mdt X picked up clearance from clearance delivery. Cleared to fly runway heading, maintain 5000'. Taxi out. While holding short we were reclred to what we both heard was 3000'. First officer read back 3000' on departure. 9, PNF, called departure and told them we were 'out of 1200', cleared to 3000',' as I always do, and received no challenge. We spotted small aircraft Y ahead, at 12 O'clock, at what appeared to be 3000'. I told the first officer to 'push it over,' and we leveled at 2400'. I asked controller if he knew that we were cleared to 3000', and also told him we had small aircraft Y in sight. He replied, 'you were only cleared to 2000.' as soon as we cleared the targets he cleared us to 10000'. I called the tower and asked them to restate our clearance limit, and tower told me that we had been cleared to 2000'. I then told the departure controller that we had been at 2000' when I called (yes, I lied on the tape to cover my butt), and that the traffic just looked closer than it really was. I indicated that I didn't have a problem with the situation. There is absolutely, positively no doubt whatsoever that we had been cleared to 3000'. We told 2 different controllers that we were going to climb to 3000' via clearance readbacks, and both readbacks went unchallenged. We didn't really take evasive action; we did stop the climb. I am positively certain that we were cleared to 3000'.

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Original NASA ASRS Text

Title: MDT X CLIMBED TO WRONG ALT AND HAD LESS THAN STANDARD SEPARATION FROM SMA Y. PLT DEVIATION. PLT DEVIATION. LCL DEP CTLRS FAILED TO HEAR INCORRECT READBACKS OF WRONG ALT. SYSTEM ERROR.

Narrative: MDT X PICKED UP CLRNC FROM CLRNC DELIVERY. CLRED TO FLY RWY HDG, MAINTAIN 5000'. TAXI OUT. WHILE HOLDING SHORT WE WERE RECLRED TO WHAT WE BOTH HEARD WAS 3000'. F/O READ BACK 3000' ON DEP. 9, PNF, CALLED DEP AND TOLD THEM WE WERE 'OUT OF 1200', CLRED TO 3000',' AS I ALWAYS DO, AND RECEIVED NO CHALLENGE. WE SPOTTED SMA Y AHEAD, AT 12 O'CLOCK, AT WHAT APPEARED TO BE 3000'. I TOLD THE F/O TO 'PUSH IT OVER,' AND WE LEVELED AT 2400'. I ASKED CTLR IF HE KNEW THAT WE WERE CLRED TO 3000', AND ALSO TOLD HIM WE HAD SMA Y IN SIGHT. HE REPLIED, 'YOU WERE ONLY CLRED TO 2000.' AS SOON AS WE CLRED THE TARGETS HE CLRED US TO 10000'. I CALLED THE TWR AND ASKED THEM TO RESTATE OUR CLRNC LIMIT, AND TWR TOLD ME THAT WE HAD BEEN CLRED TO 2000'. I THEN TOLD THE DEP CTLR THAT WE HAD BEEN AT 2000' WHEN I CALLED (YES, I LIED ON THE TAPE TO COVER MY BUTT), AND THAT THE TFC JUST LOOKED CLOSER THAN IT REALLY WAS. I INDICATED THAT I DIDN'T HAVE A PROB WITH THE SITUATION. THERE IS ABSOLUTELY, POSITIVELY NO DOUBT WHATSOEVER THAT WE HAD BEEN CLRED TO 3000'. WE TOLD 2 DIFFERENT CTLRS THAT WE WERE GOING TO CLB TO 3000' VIA CLRNC READBACKS, AND BOTH READBACKS WENT UNCHALLENGED. WE DIDN'T REALLY TAKE EVASIVE ACTION; WE DID STOP THE CLB. I AM POSITIVELY CERTAIN THAT WE WERE CLRED TO 3000'.

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.