Narrative:

While on a flight from udb to bjc, climbing through approximately FL370 to FL410, a loud and frightening bang was heard and felt in the aircraft. A strange odor was also momentarily present. Oxygen masks were donned and an emergency was declared. The aircraft diverted to las without any further incident.

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Original NASA ASRS Text

Title: A CE-560 FLT CREW EXPERIENCED A LOUD BANG FOLLOWED BY A STRANGE ODOR RESULTING IN AN EMER BEING DECLARED AND DIVERSION FOR LNDG.

Narrative: WHILE ON A FLT FROM UDB TO BJC, CLBING THROUGH APPROX FL370 TO FL410, A LOUD AND FRIGHTENING BANG WAS HEARD AND FELT IN THE ACFT. A STRANGE ODOR WAS ALSO MOMENTARILY PRESENT. OXYGEN MASKS WERE DONNED AND AN EMER WAS DECLARED. THE ACFT DIVERTED TO LAS WITHOUT ANY FURTHER INCIDENT.

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.