Narrative:

I was PF and PNF was operating radio. Earlier we had been cleared to 6000 ft and upon receiving further instructions we were cleared direct to the VOR. He also said something about '110' and I asked both other crew members if they knew what he said about '110.' the copilot said he mentioned heading 110 degrees, since that was close to the heading direct to the VOR took us. I asked him if he was sure about it, and he said he was. He also stated that he called descending to 6000 ft when he called in and he was definite we were to descend to 6000 ft. The english of the controller was very accented and he was hard to understand, but I allowed myself to be talked into believing he meant heading 110 degrees until we got direct to the VOR. I was uncomfortable with the situation and when we got to 10000 ft he advised us that we descended below our assigned flight level of 110 ft. He had changed our altitude from 6000 ft to 110 ft when he gave our direct to the VOR clearance and did not catch our readback of 'descending to 6000 ft.' I was upset at myself for allowing me to be talked into believing he said heading 110 degrees by a pilot I knew often is too laid back about those things and does not like to admit when he is unsure about something. I was not sure what the controller said, but knowing the personality of the pilot I was flying with and having a nagging feeling about the situation, I should have confirmed the altitude assigned to before I descended below 110 ft. Reading back 6000 ft was not definite enough where language differences are evident.

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Original NASA ASRS Text

Title: A GULFSTREAM 5 DSNDING INTO A EUROPEAN DEST DOES NOT CLRLY RECEIVE CLRNC AND DSNDS OUT OF AN ASSIGNED ALT.

Narrative: I WAS PF AND PNF WAS OPERATING RADIO. EARLIER WE HAD BEEN CLRED TO 6000 FT AND UPON RECEIVING FURTHER INSTRUCTIONS WE WERE CLRED DIRECT TO THE VOR. HE ALSO SAID SOMETHING ABOUT '110' AND I ASKED BOTH OTHER CREW MEMBERS IF THEY KNEW WHAT HE SAID ABOUT '110.' THE COPLT SAID HE MENTIONED HDG 110 DEGS, SINCE THAT WAS CLOSE TO THE HDG DIRECT TO THE VOR TOOK US. I ASKED HIM IF HE WAS SURE ABOUT IT, AND HE SAID HE WAS. HE ALSO STATED THAT HE CALLED DSNDING TO 6000 FT WHEN HE CALLED IN AND HE WAS DEFINITE WE WERE TO DSND TO 6000 FT. THE ENGLISH OF THE CTLR WAS VERY ACCENTED AND HE WAS HARD TO UNDERSTAND, BUT I ALLOWED MYSELF TO BE TALKED INTO BELIEVING HE MEANT HDG 110 DEGS UNTIL WE GOT DIRECT TO THE VOR. I WAS UNCOMFORTABLE WITH THE SIT AND WHEN WE GOT TO 10000 FT HE ADVISED US THAT WE DSNDED BELOW OUR ASSIGNED FLT LEVEL OF 110 FT. HE HAD CHANGED OUR ALT FROM 6000 FT TO 110 FT WHEN HE GAVE OUR DIRECT TO THE VOR CLRNC AND DID NOT CATCH OUR READBACK OF 'DSNDING TO 6000 FT.' I WAS UPSET AT MYSELF FOR ALLOWING ME TO BE TALKED INTO BELIEVING HE SAID HDG 110 DEGS BY A PLT I KNEW OFTEN IS TOO LAID BACK ABOUT THOSE THINGS AND DOES NOT LIKE TO ADMIT WHEN HE IS UNSURE ABOUT SOMETHING. I WAS NOT SURE WHAT THE CTLR SAID, BUT KNOWING THE PERSONALITY OF THE PLT I WAS FLYING WITH AND HAVING A NAGGING FEELING ABOUT THE SIT, I SHOULD HAVE CONFIRMED THE ALT ASSIGNED TO BEFORE I DSNDED BELOW 110 FT. READING BACK 6000 FT WAS NOT DEFINITE ENOUGH WHERE LANGUAGE DIFFERENCES ARE EVIDENT.

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.