Narrative:

On a flight from gtf to bil I became dazed and failed to maintain my course on the arwy or respond to ATC and ended up flying past my destination airport (bil). A fellow company pilot called me on the radio and told me to open an air vent which I did. I then landed at bil west/O incident. After landing I felt nauseated and threw up. While my airplane was being unloaded a fellow company pilot and postal employee both stated that there was a strong odor near the cockpit and that one package was wet and leaking (possibly formaldehyde). This may have been what caused my dazed condition and nausea could possibly have been prevented by use of supplemental oxygen during entire flight.

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Original NASA ASRS Text

Title: PLT OF SMA FLYING THE MAIL AT NIGHT OVERFLEW DESTINATION BIL, MT, IN ALLEDGED DAZE. OPENED AIR VENT IN COCKPIT AND MADE LANDING AT BIL WITHOUT FURTHER INCIDENT.

Narrative: ON A FLT FROM GTF TO BIL I BECAME DAZED AND FAILED TO MAINTAIN MY COURSE ON THE ARWY OR RESPOND TO ATC AND ENDED UP FLYING PAST MY DEST ARPT (BIL). A FELLOW COMPANY PLT CALLED ME ON THE RADIO AND TOLD ME TO OPEN AN AIR VENT WHICH I DID. I THEN LANDED AT BIL W/O INCIDENT. AFTER LNDG I FELT NAUSEATED AND THREW UP. WHILE MY AIRPLANE WAS BEING UNLOADED A FELLOW COMPANY PLT AND POSTAL EMPLOYEE BOTH STATED THAT THERE WAS A STRONG ODOR NEAR THE COCKPIT AND THAT ONE PACKAGE WAS WET AND LEAKING (POSSIBLY FORMALDEHYDE). THIS MAY HAVE BEEN WHAT CAUSED MY DAZED CONDITION AND NAUSEA COULD POSSIBLY HAVE BEEN PREVENTED BY USE OF SUPPLEMENTAL OXYGEN DURING ENTIRE FLT.

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.