Narrative:

On takeoff from jfk wbound departure control gave us 17000' and airspeed of 270 KTS maximum in our climb. Just east of rbl VOR we were cleared normal climb speed and frequency change to ny center. On ny center he cleared us to FL300. I read back the new altitude of 30000', and commented on never having been cleared to FL300 before. No further comment from center. Passing about 18600' center asked our assigned altitude, which we read back as FL300. He said he meant 300 KTS airspeed, not altitude, and subsequently cleared us to FL260. When the controller gave us the 300 he said it as '3-0-0' and nothing else. We had already been cleared to normal climb speed (which is around 300 KTS) by departure control and took his 300 as FL300.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR ISSUED A SPEED RESTRICTION THAT WAS INTERPRETED BY THE FLT CREW AS AN ASSIGNED ALT.

Narrative: ON TKOF FROM JFK WBOUND DEP CTL GAVE US 17000' AND AIRSPD OF 270 KTS MAX IN OUR CLB. JUST E OF RBL VOR WE WERE CLRED NORMAL CLB SPD AND FREQ CHANGE TO NY CENTER. ON NY CENTER HE CLRED US TO FL300. I READ BACK THE NEW ALT OF 30000', AND COMMENTED ON NEVER HAVING BEEN CLRED TO FL300 BEFORE. NO FURTHER COMMENT FROM CENTER. PASSING ABOUT 18600' CENTER ASKED OUR ASSIGNED ALT, WHICH WE READ BACK AS FL300. HE SAID HE MEANT 300 KTS AIRSPD, NOT ALT, AND SUBSEQUENTLY CLRED US TO FL260. WHEN THE CTLR GAVE US THE 300 HE SAID IT AS '3-0-0' AND NOTHING ELSE. WE HAD ALREADY BEEN CLRED TO NORMAL CLB SPD (WHICH IS AROUND 300 KTS) BY DEP CTL AND TOOK HIS 300 AS FL300.

Data retrieved from NASA's ASRS site as of August 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.