Narrative:

During pushback, we found that the zero fuel weight trim was out of limits by 1/10 of a unit for winter weights. We contacted houston operations, and were told that we were using summer trim limits. For summer trim limits the trim was within limits, so we continued. The flight was normal. We later found out that for our operations manual, summer trim limits are from may 1 to oct 31. Although 1/10 of a trim unit is almost impossible to read on the trim wheel, we only thought we were legal for takeoff. To prevent this from happening again, any form that has date sensitive choices should have those dates on the form somewhere!

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Original NASA ASRS Text

Title: AN ACR MLG TOOK OFF WITH THE WRONG TRIM SETTING.

Narrative: DURING PUSHBACK, WE FOUND THAT THE ZERO FUEL WT TRIM WAS OUT OF LIMITS BY 1/10 OF A UNIT FOR WINTER WTS. WE CONTACTED HOUSTON OPS, AND WERE TOLD THAT WE WERE USING SUMMER TRIM LIMITS. FOR SUMMER TRIM LIMITS THE TRIM WAS WITHIN LIMITS, SO WE CONTINUED. THE FLT WAS NORMAL. WE LATER FOUND OUT THAT FOR OUR OPS MANUAL, SUMMER TRIM LIMITS ARE FROM MAY 1 TO OCT 31. ALTHOUGH 1/10 OF A TRIM UNIT IS ALMOST IMPOSSIBLE TO READ ON THE TRIM WHEEL, WE ONLY THOUGHT WE WERE LEGAL FOR TKOF. TO PREVENT THIS FROM HAPPENING AGAIN, ANY FORM THAT HAS DATE SENSITIVE CHOICES SHOULD HAVE THOSE DATES ON THE FORM SOMEWHERE!

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.