A B737-300 stabilizer trim is set at an incorrect setting in accordance with the ACARS weight manife...

Attributes
ACN	534159
Time
Date	200201
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : bos.airport
State Reference	MA
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	ground : preflight
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : multi engine pilot : commercial pilot : instrument
ASRS Report	534159
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	534744
Events
Anomaly	aircraft equipment problem : critical non adherence : company policies other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : detected after the fact
Consequence	other
Supplementary
Problem Areas	Company Aircraft
Primary Problem	Company

Narrative:

Before takeoff, received the final weight manifest as usual over the ACARS and entered the final numbers into the FMC. Final zero fuel weight was supposedly 82.3 and a final trim setting of 5.1 for takeoff. Just after takeoff, the captain told me that it felt like he almost over rotated and that the back pressure at takeoff was extremely light. About 10 mins after takeoff, I noticed the message light blinking on the ACARS indicating a message was waiting. It was a new final weight manifest from operations sent to us 5 mins after we already departed! New zero fuel weight 80.2 and new trim setting of 4.5. Operations screwed up. This explains why the controls felt so light to the captain at rotation. Seems like a small math error but it almost caused us to have a tail strike on takeoff. Supplemental information from acn 534744: control sensitivity was very light with associated quicker than normal rotation rate. Pitch stopped at approximately 8 degrees aircraft nose up with subsequent liftoff. A second set of weights was transmitted and received while passing through approximately 14000 ft MSL on climb out.

Original NASA ASRS Text

Title: A B737-300 STABILIZER TRIM IS SET AT AN INCORRECT SETTING IN ACCORDANCE WITH THE ACARS WT MANIFEST SETTING, RESULTING IN A NEAR OVER ROTATION ON TKOF AT BOS, MA.

Narrative: BEFORE TKOF, RECEIVED THE FINAL WT MANIFEST AS USUAL OVER THE ACARS AND ENTERED THE FINAL NUMBERS INTO THE FMC. FINAL ZERO FUEL WT WAS SUPPOSEDLY 82.3 AND A FINAL TRIM SETTING OF 5.1 FOR TKOF. JUST AFTER TKOF, THE CAPT TOLD ME THAT IT FELT LIKE HE ALMOST OVER ROTATED AND THAT THE BACK PRESSURE AT TKOF WAS EXTREMELY LIGHT. ABOUT 10 MINS AFTER TKOF, I NOTICED THE MESSAGE LIGHT BLINKING ON THE ACARS INDICATING A MESSAGE WAS WAITING. IT WAS A NEW FINAL WT MANIFEST FROM OPS SENT TO US 5 MINS AFTER WE ALREADY DEPARTED! NEW ZERO FUEL WT 80.2 AND NEW TRIM SETTING OF 4.5. OPS SCREWED UP. THIS EXPLAINS WHY THE CTLS FELT SO LIGHT TO THE CAPT AT ROTATION. SEEMS LIKE A SMALL MATH ERROR BUT IT ALMOST CAUSED US TO HAVE A TAIL STRIKE ON TKOF. SUPPLEMENTAL INFO FROM ACN 534744: CTL SENSITIVITY WAS VERY LIGHT WITH ASSOCIATED QUICKER THAN NORMAL ROTATION RATE. PITCH STOPPED AT APPROX 8 DEGS ACFT NOSE UP WITH SUBSEQUENT LIFTOFF. A SECOND SET OF WTS WAS XMITTED AND RECEIVED WHILE PASSING THROUGH APPROX 14000 FT MSL ON CLBOUT.

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.

A B737-300 stabilizer trim is set at an incorrect setting in accordance with the ACARS weight manifest setting, resulting in a near over rotation on takeoff at bos, ma.