Narrative:

Company not allowing enough time for proper route. Places pilot behind schedule constantly. In flight, trying to make up time set autoplt for 5000 ft. Approach was on #1 communication. Company on #2 communication. Receiving and relaying messages for company and preparing forms for next leg due to schedule rush. Aircraft went into gradual descent leveling off perfectly at 4000 ft from 5000 ft. Busy with unnecessary work in cockpit. Altitude differences not noticed. Approach called and asked for atl report. I reported 4000 ft. They asked again. I said 4000 ft, still working on forms. I questioned my altitude. Approach asked if I've been there awhile. I said yes. Now wondering why? I realized I was 1000 ft off and climbed as soon as possible to 5000 ft. I reported I was at 5000 ft. Controller asked altitude again. I reported 5150 ft. He gave me altimeter setting first officer 30.22. I reported 30.16. He said my altimeter was reading 4300 ft. I said I would turn it off. The approved climb must have layed in the mode C. The controller didn't have a problem at that time with what happened. Note: the problem could have been avoided by less hours on pilots' work week. Company allowing time to do job properly. The pilot not allowing himself to be rushed and to fly the plane. The situation was pilot error. Luckily it was in fl and no other traffic. There is no excuse for pilot error. The industry will have to design to prevent this, for people will try their best to be on time and make money, which in this case, took the pilots mind off of what should have been done. Single pilot freight I've been doing my whole life. I've quit my job because I've been becoming fatigued too easily now.

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Original NASA ASRS Text

Title: ATX SMT TWIN EXCURSION FROM ASSIGNED ALT.

Narrative: COMPANY NOT ALLOWING ENOUGH TIME FOR PROPER RTE. PLACES PLT BEHIND SCHEDULE CONSTANTLY. IN FLT, TRYING TO MAKE UP TIME SET AUTOPLT FOR 5000 FT. APCH WAS ON #1 COM. COMPANY ON #2 COM. RECEIVING AND RELAYING MESSAGES FOR COMPANY AND PREPARING FORMS FOR NEXT LEG DUE TO SCHEDULE RUSH. ACFT WENT INTO GRADUAL DSCNT LEVELING OFF PERFECTLY AT 4000 FT FROM 5000 FT. BUSY WITH UNNECESSARY WORK IN COCKPIT. ALT DIFFERENCES NOT NOTICED. APCH CALLED AND ASKED FOR ATL RPT. I RPTED 4000 FT. THEY ASKED AGAIN. I SAID 4000 FT, STILL WORKING ON FORMS. I QUESTIONED MY ALT. APCH ASKED IF I'VE BEEN THERE AWHILE. I SAID YES. NOW WONDERING WHY? I REALIZED I WAS 1000 FT OFF AND CLBED AS SOON AS POSSIBLE TO 5000 FT. I RPTED I WAS AT 5000 FT. CTLR ASKED ALT AGAIN. I RPTED 5150 FT. HE GAVE ME ALTIMETER SETTING FO 30.22. I RPTED 30.16. HE SAID MY ALTIMETER WAS READING 4300 FT. I SAID I WOULD TURN IT OFF. THE APPROVED CLB MUST HAVE LAYED IN THE MODE C. THE CTLR DIDN'T HAVE A PROB AT THAT TIME WITH WHAT HAPPENED. NOTE: THE PROB COULD HAVE BEEN AVOIDED BY LESS HRS ON PLTS' WORK WEEK. COMPANY ALLOWING TIME TO DO JOB PROPERLY. THE PLT NOT ALLOWING HIMSELF TO BE RUSHED AND TO FLY THE PLANE. THE SIT WAS PLT ERROR. LUCKILY IT WAS IN FL AND NO OTHER TFC. THERE IS NO EXCUSE FOR PLT ERROR. THE INDUSTRY WILL HAVE TO DESIGN TO PREVENT THIS, FOR PEOPLE WILL TRY THEIR BEST TO BE ON TIME AND MAKE MONEY, WHICH IN THIS CASE, TOOK THE PLTS MIND OFF OF WHAT SHOULD HAVE BEEN DONE. SINGLE PLT FREIGHT I'VE BEEN DOING MY WHOLE LIFE. I'VE QUIT MY JOB BECAUSE I'VE BEEN BECOMING FATIGUED TOO EASILY NOW.

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.