Narrative:

Flight was en route from jfk to osa. The flight required an augmented crew and first officer and I relieved captain and first officer. Shortly after passing nome. We were briefed regarding the flight status and proceeded to verify position and programming of our route. Commonly on this route, center requires when a flight can climb to an altitude compatible with oceanic requirements and commonly issues an expected time or location to climb. We were unsure of our altitude clearance; whether we were cleared to climb to FL370 or cleared to expect FL370. Center communications are not available in that area and comrdo was difficult at that time and at best, a slow relay from center. I remained at FL350 until reaching anc center, about 10 mins prior to neeva. They advised that we had been cleared to FL370. At neeva intersection, I reported FL350 in error and center questioned the altitude. I acknowledged the error in reporting, and confirmed the correct altitude, FL370. There apparently remained a question in center's mind as to our altitude but no further inquiry was made and altitude reporting must have confirmed our altitude. A form 8020-17 was initiated by center and an occurrence report submitted to company.

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Original NASA ASRS Text

Title: CAPT OF ACR WDB ACFT MISUNDERSTOOD CLRNC AND REMAINED AT ALT INSTEAD OF CLBING TO NEWLY ASSIGNED ALT DURING HIGH ALT OCEANIC CRUISE.

Narrative: FLT WAS ENRTE FROM JFK TO OSA. THE FLT REQUIRED AN AUGMENTED CREW AND FO AND I RELIEVED CAPT AND FO. SHORTLY AFTER PASSING NOME. WE WERE BRIEFED REGARDING THE FLT STATUS AND PROCEEDED TO VERIFY POS AND PROGRAMMING OF OUR RTE. COMMONLY ON THIS RTE, CTR REQUIRES WHEN A FLT CAN CLB TO AN ALT COMPATIBLE WITH OCEANIC REQUIREMENTS AND COMMONLY ISSUES AN EXPECTED TIME OR LOCATION TO CLB. WE WERE UNSURE OF OUR ALT CLRNC; WHETHER WE WERE CLRED TO CLB TO FL370 OR CLRED TO EXPECT FL370. CTR COMS ARE NOT AVAILABLE IN THAT AREA AND COMRDO WAS DIFFICULT AT THAT TIME AND AT BEST, A SLOW RELAY FROM CTR. I REMAINED AT FL350 UNTIL REACHING ANC CTR, ABOUT 10 MINS PRIOR TO NEEVA. THEY ADVISED THAT WE HAD BEEN CLRED TO FL370. AT NEEVA INTXN, I RPTED FL350 IN ERROR AND CTR QUESTIONED THE ALT. I ACKNOWLEDGED THE ERROR IN RPTING, AND CONFIRMED THE CORRECT ALT, FL370. THERE APPARENTLY REMAINED A QUESTION IN CTR'S MIND AS TO OUR ALT BUT NO FURTHER INQUIRY WAS MADE AND ALT RPTING MUST HAVE CONFIRMED OUR ALT. A FORM 8020-17 WAS INITIATED BY CTR AND AN OCCURRENCE RPT SUBMITTED TO COMPANY.

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.