Narrative:

Battery overheated causing strong burning smell in cockpit. Diverted to ZZZZ. I had to speak foreign language to the controllers. If I had not spoken foreign language; there would have been mass confusion. I used pan pan pan; and they effectively had no idea what was going on.

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Original NASA ASRS Text

Title: B767-300 FLT CREW HAS FUMES IN COCKPIT AND DIVERTS FOR LNDG.

Narrative: BATTERY OVERHEATED CAUSING STRONG BURNING SMELL IN COCKPIT. DIVERTED TO ZZZZ. I HAD TO SPEAK FOREIGN LANGUAGE TO THE CTLRS. IF I HAD NOT SPOKEN FOREIGN LANGUAGE; THERE WOULD HAVE BEEN MASS CONFUSION. I USED PAN PAN PAN; AND THEY EFFECTIVELY HAD NO IDEA WHAT WAS GOING ON.

Data retrieved from NASA's ASRS site as of January 2009 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.