Narrative:

We were at FL240 outbound from cur, after passing inbound traffic at FL250 we were cleared to climb and maintain FL350. 75 mi north of cur during climb, cur controller asked for our altitude which we told was FL313 for FL350. No other instructions or questions were heard from cur control. When we called at penko intersection FL350, cur control told us that he had told us he previously issued a clearance to descend immediately to FL310 for crossing traffic. We never heard or acknowledged that clearance therefore when we crossed the traffic we were at FL350 and traffic was at FL330. No conflict with that traffic occurred.

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Original NASA ASRS Text

Title: ACFT CTLR MISCOM OF ALT CLRNC.

Narrative: WE WERE AT FL240 OUTBOUND FROM CUR, AFTER PASSING INBOUND TFC AT FL250 WE WERE CLRED TO CLB AND MAINTAIN FL350. 75 MI N OF CUR DURING CLB, CUR CTLR ASKED FOR OUR ALT WHICH WE TOLD WAS FL313 FOR FL350. NO OTHER INSTRUCTIONS OR QUESTIONS WERE HEARD FROM CUR CTL. WHEN WE CALLED AT PENKO INTXN FL350, CUR CTL TOLD US THAT HE HAD TOLD US HE PREVIOUSLY ISSUED A CLRNC TO DSND IMMEDIATELY TO FL310 FOR XING TFC. WE NEVER HEARD OR ACKNOWLEDGED THAT CLRNC THEREFORE WHEN WE CROSSED THE TFC WE WERE AT FL350 AND TFC WAS AT FL330. NO CONFLICT WITH THAT TFC OCCURRED.

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.