Narrative:

During our normal preflight duties; we input passenger and bag counts to the FMS. All of the numbers we received from cabin and ramp personnel; as well as our fuel load; seemed well within normal limits. However; the solution we obtained from the FMS indicated that we were out of balance; and needed to either move bags from the forward baggage compartment to the aft compartment; or move first class passengers to the aft cabin. We elected to move 8 bags from forward to aft; and received a solution that indicated we were within limits. During taxi to the departure runway; everything felt normal. First officer performed the takeoff; and stated that as we approached V1; he had to push forward and trim nose down (from a T.O. Setting of 8.4 to about 5.0) to keep the aircraft at the proper pitch. The flight was completed with a normal landing at our destination airport. For the return flight; we again received and input what seemed to be normal numbers. Again; the solution indicated an out-of-balance condition. At that point; we were obviously quite suspicious and called dispatch to suggest that the basic operating index (or moment) may have been incorrect on their end. After a group effort coordinated by dispatch; new moment numbers were put in the system for this aircraft. We reentered our load numbers; received a more reasonable solution; and completed the flight. We found out during our delay that the aircraft had been weighed prior to our first flight; and that incorrect numbers were put in the database system. I'm confident that that mistake won't be made again. That was the obvious cause of the incident I've described. However; both the first officer and I had a strong gut feeling before our original departure that something just wasn't right. We should have acted at that time to resolve the issue rather than risk a departure stall. We got lucky this time. Moral: follow your gut.

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Original NASA ASRS Text

Title: A CRJ-900 had been weighed prior to the crew's first flight and incorrect numbers entered into the Basic Operating Index database which made the aircraft out of its normal trim limit for takeoff.

Narrative: During our normal preflight duties; we input passenger and bag counts to the FMS. All of the numbers we received from cabin and ramp personnel; as well as our fuel load; seemed well within normal limits. However; the solution we obtained from the FMS indicated that we were out of balance; and needed to either move bags from the forward baggage compartment to the aft compartment; or move first class passengers to the aft cabin. We elected to move 8 bags from forward to aft; and received a solution that indicated we were within limits. During taxi to the departure runway; everything felt normal. First Officer performed the takeoff; and stated that as we approached V1; he had to push forward and trim nose down (from a T.O. setting of 8.4 to about 5.0) to keep the aircraft at the proper pitch. The flight was completed with a normal landing at our destination airport. For the return flight; we again received and input what seemed to be normal numbers. Again; the solution indicated an out-of-balance condition. At that point; we were obviously quite suspicious and called dispatch to suggest that the Basic Operating Index (or moment) may have been incorrect on their end. After a group effort coordinated by Dispatch; new moment numbers were put in the system for this aircraft. We reentered our load numbers; received a more reasonable solution; and completed the flight. We found out during our delay that the aircraft had been weighed prior to our first flight; and that incorrect numbers were put in the database system. I'm confident that that mistake won't be made again. That was the obvious cause of the incident I've described. However; both the First Officer and I had a strong gut feeling before our original departure that something just wasn't right. We should have acted at that time to resolve the issue rather than risk a departure stall. We got lucky this time. Moral: follow your gut.

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.