Narrative:

It was my leg on this flight, and I had the controls from the left seat. Our aircraft was an mdt. As a crew, we had flown the aircraft uneventfully on 3 previous legs that day. The preflight was not unusual. My first officer had completed the load manifest for the flight before departing the blocks. It showed that we had 42 bags (corrected from an initial count of 40) and 30 passengers. We made the bag count correction on our original load manifest , but failed to do so for the copy we left behind because of the time involved and our desire to make an on time departure. We were well below our maximum takeoff weight and well within balance for our passenger/bag confign. All the checklists up to takeoff were performed normally. The flaps were set to 15 degrees, the trim was set to the forward takeoff position and the V speeds for our weight were briefed. The takeoff roll was not unusual. Takeoff power was achieved on all engines. The standard calls were made and the aircraft accelerated normally. At 10 KTS before V1, however, the aircraft rotated on its own and got airborne. For a few seconds, I pushed the yoke forward and rolled the elevator trim to full forward to keep the aircraft from getting too slow. I noted this event with my first officer. We cleaned up the aircraft as the tower switched us over to departure. It was at that point that I decided to return to our departure airport. Although I was able to control the aircraft without difficulty, I did not feel that it was safe to continue the flight if I had to do so with full nose down trim. I instructed my first officer to inform departure that we wanted to return to the field. They turned us to a downwind for a visual approach to the landing runway. The after takeoff, in range and landing checklists were performed. The flaps 25 landing was soft and uneventful. Equipment was standing by even though we didn't declare an emergency. The flight lasted about 5 mins and during most of the flight, the elevator trim was at the full nose down setting. I, along with my first officer and the station manager, counted the bags on our flight and confirmed that there were 42 bags on board. Most of the bags were large. Our service control weighed 34 at a total of 1600 pounds. Unfortunately, not all of the bags appear to have made it to the scale for weighing. If I assume, then, that each bag weighed 47 pounds and there were 42 bags on board, then our total bag weight was approximately 2000 pounds. This exceeded our maximum cargo weight of 1800 pounds for 30 passengers. Since the baggage compartment is located in the tail, the out of limits balance condition made us tail heavy. The passenger seating assignments are being reviewed by our company. No passengers were seated in the first two rows and my flight attendant confessed to me that she had allowed passengers to situation in row 14, which should have been blocked off. Our maintenance told me that the elevator spring tabs for our aircraft may be out of adjustment. It takes a string of events to contribute to an accident or incident. This incident appears at this point to have been caused by an out of balance condition and mechanical problems. Lessons learned: bags usually weigh more that the assumed weight of 23.5 pounds. Until the FAA changes that number, we will continue to takeoff in a tail heavy condition without knowing it. Don't be afraid to declare an emergency. Brief flight attendants to comply strictly with seating rules as they relate to weight and balance. Correct all copies of the load manifest if necessary. It's important.

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Original NASA ASRS Text

Title: TEMPORARY LOSS OF ACFT CTL ON ROTATION ACCOUNT OF A WT AND BALANCE PROBLEM AND AN INACCURATE WT MANIFEST.

Narrative: IT WAS MY LEG ON THIS FLT, AND I HAD THE CTLS FROM THE L SEAT. OUR ACFT WAS AN MDT. AS A CREW, WE HAD FLOWN THE ACFT UNEVENTFULLY ON 3 PREVIOUS LEGS THAT DAY. THE PREFLT WAS NOT UNUSUAL. MY FO HAD COMPLETED THE LOAD MANIFEST FOR THE FLT BEFORE DEPARTING THE BLOCKS. IT SHOWED THAT WE HAD 42 BAGS (CORRECTED FROM AN INITIAL COUNT OF 40) AND 30 PAXS. WE MADE THE BAG COUNT CORRECTION ON OUR ORIGINAL LOAD MANIFEST , BUT FAILED TO DO SO FOR THE COPY WE LEFT BEHIND BECAUSE OF THE TIME INVOLVED AND OUR DESIRE TO MAKE AN ON TIME DEP. WE WERE WELL BELOW OUR MAX TKOF WT AND WELL WITHIN BALANCE FOR OUR PAX/BAG CONFIGN. ALL THE CHKLISTS UP TO TKOF WERE PERFORMED NORMALLY. THE FLAPS WERE SET TO 15 DEGS, THE TRIM WAS SET TO THE FORWARD TKOF POS AND THE V SPDS FOR OUR WEIGHT WERE BRIEFED. THE TKOF ROLL WAS NOT UNUSUAL. TKOF PWR WAS ACHIEVED ON ALL ENGS. THE STANDARD CALLS WERE MADE AND THE ACFT ACCELERATED NORMALLY. AT 10 KTS BEFORE V1, HOWEVER, THE ACFT ROTATED ON ITS OWN AND GOT AIRBORNE. FOR A FEW SECONDS, I PUSHED THE YOKE FORWARD AND ROLLED THE ELEVATOR TRIM TO FULL FORWARD TO KEEP THE ACFT FROM GETTING TOO SLOW. I NOTED THIS EVENT WITH MY FO. WE CLEANED UP THE ACFT AS THE TWR SWITCHED US OVER TO DEP. IT WAS AT THAT POINT THAT I DECIDED TO RETURN TO OUR DEP ARPT. ALTHOUGH I WAS ABLE TO CTL THE ACFT WITHOUT DIFFICULTY, I DID NOT FEEL THAT IT WAS SAFE TO CONTINUE THE FLT IF I HAD TO DO SO WITH FULL NOSE DOWN TRIM. I INSTRUCTED MY FO TO INFORM DEP THAT WE WANTED TO RETURN TO THE FIELD. THEY TURNED US TO A DOWNWIND FOR A VISUAL APCH TO THE LNDG RWY. THE AFTER TKOF, IN RANGE AND LNDG CHKLISTS WERE PERFORMED. THE FLAPS 25 LNDG WAS SOFT AND UNEVENTFUL. EQUIP WAS STANDING BY EVEN THOUGH WE DIDN'T DECLARE AN EMER. THE FLT LASTED ABOUT 5 MINS AND DURING MOST OF THE FLT, THE ELEVATOR TRIM WAS AT THE FULL NOSE DOWN SETTING. I, ALONG WITH MY FO AND THE STATION MGR, COUNTED THE BAGS ON OUR FLT AND CONFIRMED THAT THERE WERE 42 BAGS ON BOARD. MOST OF THE BAGS WERE LARGE. OUR SERVICE CTL WEIGHED 34 AT A TOTAL OF 1600 LBS. UNFORTUNATELY, NOT ALL OF THE BAGS APPEAR TO HAVE MADE IT TO THE SCALE FOR WEIGHING. IF I ASSUME, THEN, THAT EACH BAG WEIGHED 47 LBS AND THERE WERE 42 BAGS ON BOARD, THEN OUR TOTAL BAG WEIGHT WAS APPROX 2000 LBS. THIS EXCEEDED OUR MAX CARGO WEIGHT OF 1800 LBS FOR 30 PAXS. SINCE THE BAGGAGE COMPARTMENT IS LOCATED IN THE TAIL, THE OUT OF LIMITS BALANCE CONDITION MADE US TAIL HVY. THE PAX SEATING ASSIGNMENTS ARE BEING REVIEWED BY OUR COMPANY. NO PAXS WERE SEATED IN THE FIRST TWO ROWS AND MY FLT ATTENDANT CONFESSED TO ME THAT SHE HAD ALLOWED PAXS TO SIT IN ROW 14, WHICH SHOULD HAVE BEEN BLOCKED OFF. OUR MAINT TOLD ME THAT THE ELEVATOR SPRING TABS FOR OUR ACFT MAY BE OUT OF ADJUSTMENT. IT TAKES A STRING OF EVENTS TO CONTRIBUTE TO AN ACCIDENT OR INCIDENT. THIS INCIDENT APPEARS AT THIS POINT TO HAVE BEEN CAUSED BY AN OUT OF BALANCE CONDITION AND MECHANICAL PROBLEMS. LESSONS LEARNED: BAGS USUALLY WEIGH MORE THAT THE ASSUMED WT OF 23.5 LBS. UNTIL THE FAA CHANGES THAT NUMBER, WE WILL CONTINUE TO TKOF IN A TAIL HVY CONDITION WITHOUT KNOWING IT. DON'T BE AFRAID TO DECLARE AN EMER. BRIEF FLT ATTENDANTS TO COMPLY STRICTLY WITH SEATING RULES AS THEY RELATE TO WT AND BALANCE. CORRECT ALL COPIES OF THE LOAD MANIFEST IF NECESSARY. IT'S IMPORTANT.

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.