Flight crew of B737 receive tardy revision to aircraft ZFW during takeoff roll.

Attributes
ACN	666963
Time
Date	200508
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : ord.airport
State Reference	IL
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B737-500
Operating Under FAR Part	Part 121
Flight Phase	ground : takeoff roll
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 220 flight time total : 17000 flight time type : 10000
ASRS Report	666963
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	non adherence : company policies non adherence : far non adherence : published procedure other anomaly other
Independent Detector	other flight crewa other other : 3
Resolutory Action	none taken : anomaly accepted
Consequence	other
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft Company
Primary Problem	Company

Narrative:

Incident: load planning sent notification that flight weights were inaccurate during or just after takeoff roll initiation. No FARS violated and flight was operated within SOP and legal load and performance parameters. Immediately following liftoff the ACARS 'message' light was blinking. The message was that ord needed to revise the zero fuel weight of the aircraft. The final numbers were inaccurate by 1000 pounds; potentially a fatal error. This situation should not be allowed to occur in the future. It was fortunate that there were no illegalities and the data were within allowable performance limitations. In the future; stations should be prohibited from sending 'final' numbers that ar not final. The takeoff roll is not the time to get an unexpected message saying weights need be revised.

Original NASA ASRS Text

Title: FLT CREW OF B737 RECEIVE TARDY REVISION TO ACFT ZFW DURING TKOF ROLL.

Narrative: INCIDENT: LOAD PLANNING SENT NOTIFICATION THAT FLT WTS WERE INACCURATE DURING OR JUST AFTER TAKEOFF ROLL INITIATION. NO FARS VIOLATED AND FLT WAS OPERATED WITHIN SOP AND LEGAL LOAD AND PERFORMANCE PARAMETERS. IMMEDIATELY FOLLOWING LIFTOFF THE ACARS 'MSG' LIGHT WAS BLINKING. THE MESSAGE WAS THAT ORD NEEDED TO REVISE THE ZERO FUEL WT OF THE ACFT. THE FINAL NUMBERS WERE INACCURATE BY 1000 LBS; POTENTIALLY A FATAL ERROR. THIS SIT SHOULD NOT BE ALLOWED TO OCCUR IN THE FUTURE. IT WAS FORTUNATE THAT THERE WERE NO ILLEGALITIES AND THE DATA WERE WITHIN ALLOWABLE PERFORMANCE LIMITATIONS. IN THE FUTURE; STATIONS SHOULD BE PROHIBITED FROM SENDING 'FINAL' NUMBERS THAT AR NOT FINAL. THE TAKEOFF ROLL IS NOT THE TIME TO GET AN UNEXPECTED MESSAGE SAYING WTS NEED BE REVISED.

Data retrieved from NASA's ASRS site as of January 2009 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.