Narrative:

Air carrier X checked on, climbing to 15000 ft. I cleared the aircraft to FL370, the aircraft read back FL370. The aircraft had requested FL350 on initial proposed flight plan. The aircraft did not question the higher altitude. When the aircraft was manually handed off to vancouver west, coordination to FL350 and direct port hardy was coordinated. About 6-7 mins later, vancouver west called the new controller and questioned the aircraft at FL370. Canada had been experiencing a radar problem at the time, and the receiving controller missed the altitude climbing to FL370, not FL350.

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Original NASA ASRS Text

Title: ZSE CTLR COORD EFFORTS WITH CZVR CTLR FAILED TO CONFIRM FINAL ASSIGNED ALT OF B757 BEING HANDED OFF.

Narrative: ACR X CHKED ON, CLBING TO 15000 FT. I CLRED THE ACFT TO FL370, THE ACFT READ BACK FL370. THE ACFT HAD REQUESTED FL350 ON INITIAL PROPOSED FLT PLAN. THE ACFT DID NOT QUESTION THE HIGHER ALT. WHEN THE ACFT WAS MANUALLY HANDED OFF TO VANCOUVER WEST, COORD TO FL350 AND DIRECT PORT HARDY WAS COORDINATED. ABOUT 6-7 MINS LATER, VANCOUVER WEST CALLED THE NEW CTLR AND QUESTIONED THE ACFT AT FL370. CANADA HAD BEEN EXPERIENCING A RADAR PROB AT THE TIME, AND THE RECEIVING CTLR MISSED THE ALT CLBING TO FL370, NOT FL350.

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.