Narrative:

We were at 340; amazonica handed us off and said maintain 350. I did not request 350; so I read it back very slowly and clearly; FL350. We were near 360 degrees of heading. We climbed to 350. I made 2 more position reports at 350 and no one questioned it. When I checked in with georgetown ATC; he was surprised we were at 350 and told us to descend to 340. He asked us who gave us FL350. We told him the frequency and time. There were no traffic conflicts.

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Original NASA ASRS Text

Title: B767-300 over South America understood it was cleared to an altitude inappropriate for their direction of flight. Despite position reports the altitude was not questioned until later in the flight.

Narrative: We were at 340; Amazonica handed us off and said maintain 350. I did not request 350; so I read it back very slowly and clearly; FL350. We were near 360 degrees of heading. We climbed to 350. I made 2 more position reports at 350 and no one questioned it. When I checked in with Georgetown ATC; he was surprised we were at 350 and told us to descend to 340. He asked us who gave us FL350. We told him the frequency and time. There were no traffic conflicts.

Data retrieved from NASA's ASRS site as of April 2012 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.