Narrative:

Prior to pushback; a pre-departure briefing was accomplished: (captain) pilot flying and (first officer) pilot monitoring. The ATIS report indicated VFR weather with gusty crosswinds 20-25 knots. Even though wind-shear was not being reported; I advocated using max thrust with flaps 20. The captain and I discussed it and agreed it was the best option for takeoff. After pulling up the ACARS takeoff data message for our runway; I gave a performance briefing based on these preferences. The planned TOGW was approximately 854.0; maximum EPR 1.51; and N1 of 98. After pushback and sometime during engine start-up; the final weights were received. Once all engines were started; the primary relief pilot handed me the print out of the final weights. After review; I entered the final ZFW value into the CDU. I noted a tow change of (-907 lbs) and verbalized this out loud. The captain acknowledged the change. I left the CDU on the performance page for final TOGW reference and for the primary relief pilot to call up the ACARS final takeoff data message based on the final TOGW. During our taxi out; the primary relief pilot handed me the printed final takeoff data. For reasons which I still cannot fully explain; my eyes fell primarily to the max EPR; N1; and flap 20 information and not the TOGW and accompanying v-speeds. Because of the slight change in weight (-907 lbs) the best explanation I can offer is that I was not expecting the final performance values and speeds to vary significantly from what I previously briefed. This oversight caused me to fail in discovering that the primary relief pilot had mistakenly used the final ZFW value instead of the final TOGW for the calculation of the final takeoff performance data. As we continued our taxi out to the runway; I entered the v-speeds for max EPR without any scrutiny. The v-speeds entered into the CDU were based on the wrong weight. Once the final takeoff data message was passed forward; I read out loud and briefed the updated data for the captain and relief first officer. After this; I placed the printed data message on the center console for the captain and relief pilots to re-verify. Remarkably; neither the captain nor the relief pilots caught any of the errors. As we approached the end of the runway; we ran the before takeoff checklist. The last line on the checklist before final items is MCP. Both the captain and I recalled that V2 response was read at 180 which is a typical value for a heavyweight take-off. I believe the best reason to help explain why the MCP V2 speed was set at this value was again due to my pre-expectation that the final figures would be very close to my earlier performance briefing and also because of the many years of experience on the airplane; intuitively; that value is a normal value to be seen. As we started the takeoff roll and began accelerating; visually; I could see on the nd that V1 and vr were very close together (not typical for a heavyweight takeoff) at that point; I think the captain and I both instantly detected something was not right about the speeds. Thankfully; instead of forcing the rotation; the captain allowed the airplane to continue accelerating down the runway developing sufficient speed on the main gear prior to lifting off and becoming airborne. At a safe altitude; we began a review of the takeoff data. A conference call with dispatch and the duty manager took place explaining to them the error and the possibility of a tail strike even though the cabin crew; when queried; did not notice or hear anything in the cabin out of the ordinary throughout the takeoff. All aircraft systems appeared normal and after discussion; a collective decision was made to continue. Contributing factor #1 (dispatch release): at flight planning in ops; this particular captain's routine is to print out and use his own fp (flight plan) for use during the flight instead of using the mfp (master flight plan). What the rest of the crew did not realize anytime duringplanning was that the captain had fp (release #2) while the rest of the crew was using master fp (release #1). At the airplane; the first officer based all FMC and ACARS inputs based on the master fp (release #1). This created confusion and a distraction during the critical time after pushback and engine start when performance calculations were being performed and the aircraft was being configured for taxi. This diverted my attention and focus away from normal duties and is when the fp release discrepancy was discovered. Contributing factor #2 (final weight manifest): when the final weight manifest figures were received from lp (load planning) the ZFW was loaded into the CDU and I observed that the aircraft gross weight value increased when the final weight manifest indicated that takeoff weight change had dropped (-907 lbs). This inconsistency; which had to be reconciled; caused another distraction and was created by contributing factor #1. Contributing factor #3 (incorrect takeoff performance data): the primary relief pilot mistakenly used the final ZFW for the TOGW figure when requesting the final takeoff data message. The ACARS log reflected that (2) requests were made using the ZFW instead of the TOGW and the error was never caught and corrected. These were the final figures passed forward to be used for takeoff. In all the years that I have been flying the 747; this error has never happened on any of my flights. Contributing factor #4 (complacency; SOP discipline): I have always prided myself as a professional pilot being vigilant; conscientious; and safe. In retrospect; there were many things that got by me on this flight that I should have caught. I let my guard down and as a result; let myself down; and my crew.

Google
 

Original NASA ASRS Text

Title: B747 flight crew describes the circumstances that led up to the entry of incorrect V speeds into the FMC. The ZFW of 498k was used instead of the actual TOGW of 853K for the V speed calculation. The Captain detects the anomaly during the takeoff roll and delays rotation until closer to the actual V2 speed of 180 knots.

Narrative: Prior to pushback; a pre-departure briefing was accomplished: (Captain) Pilot Flying and (First Officer) Pilot Monitoring. The ATIS report indicated VFR weather with gusty crosswinds 20-25 knots. Even though wind-shear was not being reported; I advocated using Max thrust with Flaps 20. The Captain and I discussed it and agreed it was the best option for takeoff. After pulling up the ACARS Takeoff Data Message for our runway; I gave a performance briefing based on these preferences. The planned TOGW was approximately 854.0; MAX EPR 1.51; and N1 of 98. After pushback and sometime during engine start-up; the final weights were received. Once all engines were started; the Primary Relief Pilot handed me the print out of the final weights. After review; I entered the Final ZFW value into the CDU. I noted a TOW change of (-907 lbs) and verbalized this out loud. The Captain acknowledged the change. I left the CDU on the performance page for final TOGW reference and for the Primary Relief Pilot to call up the ACARS Final Takeoff Data Message based on the final TOGW. During our taxi out; the Primary Relief Pilot handed me the printed Final Takeoff Data. For reasons which I still cannot fully explain; my eyes fell primarily to the Max EPR; N1; and Flap 20 information and not the TOGW and accompanying V-speeds. Because of the slight change in weight (-907 lbs) the best explanation I can offer is that I was not expecting the final performance values and speeds to vary significantly from what I previously briefed. This oversight caused me to fail in discovering that the Primary Relief Pilot had mistakenly used the final ZFW value instead of the final TOGW for the calculation of the Final Takeoff Performance Data. As we continued our taxi out to the runway; I entered the V-speeds for Max EPR without any scrutiny. The V-speeds entered into the CDU were based on the wrong weight. Once the Final Takeoff Data Message was passed forward; I read out loud and briefed the updated data for the Captain and Relief First Officer. After this; I placed the printed data message on the center console for the Captain and relief pilots to re-verify. Remarkably; neither the Captain nor the relief pilots caught any of the errors. As we approached the end of the runway; we ran the before takeoff checklist. The last line on the checklist before Final Items is MCP. Both the Captain and I recalled that V2 response was read at 180 which is a typical value for a heavyweight take-off. I believe the best reason to help explain why the MCP V2 speed was set at this value was again due to my pre-expectation that the final figures would be very close to my earlier performance briefing and also because of the many years of experience on the airplane; intuitively; that value is a normal value to be seen. As we started the takeoff roll and began accelerating; visually; I could see on the ND that V1 and VR were very close together (not typical for a heavyweight takeoff) At that point; I think the Captain and I both instantly detected something was not right about the speeds. Thankfully; instead of forcing the rotation; the Captain allowed the airplane to continue accelerating down the runway developing sufficient speed on the main gear prior to lifting off and becoming airborne. At a safe altitude; we began a review of the Takeoff Data. A conference call with Dispatch and the Duty Manager took place explaining to them the error and the possibility of a tail strike even though the cabin crew; when queried; did not notice or hear anything in the cabin out of the ordinary throughout the takeoff. All aircraft systems appeared normal and after discussion; a collective decision was made to continue. Contributing factor #1 (Dispatch Release): At flight planning in Ops; this particular Captain's routine is to print out and use his own FP (flight plan) for use during the flight instead of using the MFP (Master Flight Plan). What the rest of the crew did not realize anytime duringplanning was that the Captain had FP (release #2) while the rest of the crew was using Master FP (release #1). At the airplane; the First Officer based all FMC and ACARS inputs based on the Master FP (release #1). This created confusion and a distraction during the critical time after pushback and engine start when performance calculations were being performed and the aircraft was being configured for taxi. This diverted my attention and focus away from normal duties and is when the FP release discrepancy was discovered. Contributing factor #2 (Final Weight Manifest): When the final weight manifest figures were received from LP (load planning) the ZFW was loaded into the CDU and I observed that the aircraft gross weight value increased when the Final Weight Manifest indicated that Takeoff Weight Change had dropped (-907 lbs). This inconsistency; which had to be reconciled; caused another distraction and was created by contributing factor #1. Contributing factor #3 (Incorrect Takeoff Performance Data): The Primary Relief Pilot mistakenly used the Final ZFW for the TOGW figure when requesting the Final Takeoff Data Message. The ACARS log reflected that (2) requests were made using the ZFW instead of the TOGW and the error was never caught and corrected. These were the final figures passed forward to be used for takeoff. In all the years that I have been flying the 747; this error has never happened on any of my flights. Contributing factor #4 (Complacency; SOP discipline): I have always prided myself as a professional pilot being vigilant; conscientious; and safe. In retrospect; there were many things that got by me on this flight that I should have caught. I let my guard down and as a result; let myself down; and my crew.

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.