Narrative:

Altitude clearance dispute. I was the captain flying when we understood and read back the climb clearing to FL350. We had been at FL230. As we were passing FL260, ZBW controller asked us if we were at FL250. We said no, that we heard and read back climb to FL350. We were then instructed to climb to FL270. When the controller cleared us to the next frequency he apologized for the mix up.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR APOLOGIZES FOR SUGGESTING THAT AN ACR CREW HAD EXCEEDED THEIR CLB CLRNC ALT WHEN HE ASSUMED IT WAS FL250 AND THE ACTUAL CLRNC WAS FL350.

Narrative: ALT CLRNC DISPUTE. I WAS THE CAPT FLYING WHEN WE UNDERSTOOD AND READ BACK THE CLB CLRING TO FL350. WE HAD BEEN AT FL230. AS WE WERE PASSING FL260, ZBW CTLR ASKED US IF WE WERE AT FL250. WE SAID NO, THAT WE HEARD AND READ BACK CLB TO FL350. WE WERE THEN INSTRUCTED TO CLB TO FL270. WHEN THE CTLR CLRED US TO THE NEXT FREQ HE APOLOGIZED FOR THE MIX UP.

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.