Narrative:

I had been a pilot with a part 91 contractor and had recently hired on as a pilot with a part 135 cargo operation. The part 91 operator asked me to fill in for a pilot that was out. I did so, inadvertently exceeding my duty time limitations under part 135. I had forgotten that the part 135 duty limits covered 'all commercial flying,' even part 91 operations. A more thorough part 135 ground school would have helped me to remember this.

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Original NASA ASRS Text

Title: AIR TAXI PLT ACCEPTS A COMMERCIAL FLT WITH PART 91 OPERATOR AND EXCEEDS HIS COMMERCIAL DUTY TIME.

Narrative: I HAD BEEN A PLT WITH A PART 91 CONTRACTOR AND HAD RECENTLY HIRED ON AS A PLT WITH A PART 135 CARGO OP. THE PART 91 OPERATOR ASKED ME TO FILL IN FOR A PLT THAT WAS OUT. I DID SO, INADVERTENTLY EXCEEDING MY DUTY TIME LIMITATIONS UNDER PART 135. I HAD FORGOTTEN THAT THE PART 135 DUTY LIMITS COVERED 'ALL COMMERCIAL FLYING,' EVEN PART 91 OPS. A MORE THOROUGH PART 135 GND SCHOOL WOULD HAVE HELPED ME TO REMEMBER THIS.

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.