Narrative:

Our flight schedule was: day 1 scheduled duty 9 hours 56 mins. Actual duty 10 hours 6 mins. Day 2 scheduled duty 5 hours 48 mins. Actual duty 4 hours 50 mins. Day 3 scheduled duty 5 hours 5 mins. Actual duty 11 hours 3 mins. Day 4 scheduled duty 9 hours 23 mins. Called in fatigued after 3 hours 26 mins. I called in fatigued after flying to ZZZ. This schedule entailed long duty days followed by minimum rest. Inability to obtain adequate sleep due to switching between evening and morning shifts unexpectedly; inability to control hotel room temperatures and outside noise. Reassignment resulting in a legal layover only on paper that had no ability to actually receive any layover beyond minimum rest at the hotel. These things lead to pilot fatigue and need to be addressed by our airline and industry wide. Month after month of minimal days off; maximum flying days and 90 hours plus shoved into a schedule is having an adverse effect on this pilot group. We are an accident waiting to happen and it will be blamed on pilot fatigue. I was fortunate to be flying with a very observant captain and we noticed the symptoms of acute fatigue in each other and promptly removed ourselves from flight duties for the remainder of our trip by notifying crew scheduling we were too fatigued to continue flying.

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Original NASA ASRS Text

Title: B737-300 FLT CREW RECOGNIZED THAT THEY WERE FATIGUED AND NOTIFIED THE AIRLINE THAT THEY WERE UNABLE TO CONTINUE AS SCHEDULED.

Narrative: OUR FLT SCHEDULE WAS: DAY 1 SCHEDULED DUTY 9 HRS 56 MINS. ACTUAL DUTY 10 HRS 6 MINS. DAY 2 SCHEDULED DUTY 5 HRS 48 MINS. ACTUAL DUTY 4 HRS 50 MINS. DAY 3 SCHEDULED DUTY 5 HRS 5 MINS. ACTUAL DUTY 11 HRS 3 MINS. DAY 4 SCHEDULED DUTY 9 HRS 23 MINS. CALLED IN FATIGUED AFTER 3 HRS 26 MINS. I CALLED IN FATIGUED AFTER FLYING TO ZZZ. THIS SCHEDULE ENTAILED LONG DUTY DAYS FOLLOWED BY MINIMUM REST. INABILITY TO OBTAIN ADEQUATE SLEEP DUE TO SWITCHING BTWN EVENING AND MORNING SHIFTS UNEXPECTEDLY; INABILITY TO CTL HOTEL ROOM TEMPS AND OUTSIDE NOISE. REASSIGNMENT RESULTING IN A LEGAL LAYOVER ONLY ON PAPER THAT HAD NO ABILITY TO ACTUALLY RECEIVE ANY LAYOVER BEYOND MINIMUM REST AT THE HOTEL. THESE THINGS LEAD TO PLT FATIGUE AND NEED TO BE ADDRESSED BY OUR AIRLINE AND INDUSTRY WIDE. MONTH AFTER MONTH OF MINIMAL DAYS OFF; MAX FLYING DAYS AND 90 HRS PLUS SHOVED INTO A SCHEDULE IS HAVING AN ADVERSE EFFECT ON THIS PLT GROUP. WE ARE AN ACCIDENT WAITING TO HAPPEN AND IT WILL BE BLAMED ON PLT FATIGUE. I WAS FORTUNATE TO BE FLYING WITH A VERY OBSERVANT CAPT AND WE NOTICED THE SYMPTOMS OF ACUTE FATIGUE IN EACH OTHER AND PROMPTLY REMOVED OURSELVES FROM FLT DUTIES FOR THE REMAINDER OF OUR TRIP BY NOTIFYING CREW SCHEDULING WE WERE TOO FATIGUED TO CONTINUE FLYING.

Data retrieved from NASA's ASRS site as of May 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.