Narrative:

I agreed to call in fatigued as a crew for the following reasons: 1) the captain appeared extremely fatigued at the time. 2) we had sat around 6 hours and were all experiencing that 'tired dullness' you get with a rolling departure time slip. 3) although still legal; our duty day was in jeopardy. Assuming we pushed 45 minutes after our assigned aircraft blocked in; we would need minimal ground delay to takeoff and stay under our maximum duty day. 4) we observed the weather getting worse; freezing drizzle with ice and snow pellets. Our experience told us the taxi out and deice would be lengthy and contribute to our lack of mental alertness and undoubtedly bust our duty day. 5) finally; we projected ahead 8 hours to our arrival; approach and landing; that made us feel uncomfortable given the high terrain and a weather forecast that was marginal. So instead of fueling; catering; loading cargo and passengers and then hopefully pushing within duty day and hoping that we would experience minimal ground delay that would include deicing and then somehow magically feeling refreshed after an atlantic crossing to execute a high threat arrival; we decided as a crew to make the fatigue call and put a stop to an unsafe chain of events that was being linked together.

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Original NASA ASRS Text

Title: B767 First Officer describes the reason for a fatigue call after a six hour rolling delay prior to an international flight.

Narrative: I agreed to call in fatigued as a crew for the following reasons: 1) The Captain appeared extremely fatigued at the time. 2) We had sat around 6 hours and were all experiencing that 'tired dullness' you get with a rolling departure time slip. 3) Although still legal; our duty day was in jeopardy. Assuming we pushed 45 minutes after our assigned aircraft blocked in; we would need minimal ground delay to takeoff and stay under our maximum duty day. 4) We observed the weather getting worse; freezing drizzle with ice and snow pellets. Our experience told us the taxi out and deice would be lengthy and contribute to our lack of mental alertness and undoubtedly bust our duty day. 5) Finally; we projected ahead 8 hours to our arrival; approach and landing; that made us feel uncomfortable given the high terrain and a weather forecast that was marginal. So instead of fueling; catering; loading cargo and passengers and then hopefully pushing within duty day and hoping that we would experience minimal ground delay that would include deicing and then somehow magically feeling refreshed after an Atlantic crossing to execute a high threat arrival; we decided as a crew to make the fatigue call and put a stop to an unsafe chain of events that was being linked together.

Data retrieved from NASA's ASRS site as of July 2013 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.