Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Time Pressure; Distraction; Confusion; Workload; Communication Breakdown
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Weight And Balance
General None Reported / Taken
Aircraft; Chart Or Publication; Procedure
I printed out a full paperwork package from the podium computer; knowing that we could not get performance data from ACARS because the ACARS was on MEL (and would need to leave a signed release/fit for duty). During the FMC set-up; we noticed the Performance Data Report (PDR) had become invalid for the proposed temperature. I returned to the podium computer and attempted to access the performance data tool program. I could not get the performance lookup program to run. The computer appeared to be blocking 'pop-ups' when I clicked the 'performance' word on the introduction page. Typically; a 'run' icon appears; but did not in this case. I contacted dispatch by telephone explaining I could not get the performance lookup tool program to run and asked if they could run performance for me. My dispatcher ran performance for 30 degrees C and said he could email the TPR to my first class email. I accessed the email and printed the new TPR. I returned to the airplane and we used the new data and completed our set-up; checklists; and pushed for departure. During rotation on the takeoff roll; I noticed a heavier nose down feel and after rotating; the aircraft did not immediately become airborne. After a few seconds; the aircraft became airborne and the climb out was more typical. We reviewed the paperwork enroute and discovered the second TPR sent by dispatch (via email) had an error. The data was appropriate for the runway; temperature; and weight. The TPR also had the correct tail number. However; the last line after tail number in the TPR read CFM56-XI believe we received data for the correct tail number; but for an incorrect model/engine. We may have had takeoff data/speeds for [the XXX-X1 model] instead of a [XXX-X2 model]. This resulted in V-speeds that were too slow. This explains the slow; heavy rotation. We did not have a tail-strike or any other incident during the takeoff. After discussing this with the dispatcher; we agreed that a data error was to blame; but when we tried to re-create the error using the same inputs; we could not reproduce the erroneous data. An erroneous data report was generated and sent to me for my departure.
An aircraft ACARS printer was inoperative so Dispatch emailed the performance data to the crew. During takeoff the nose heavy aircraft extended the takeoff roll. In flight the crew determined the V speeds were too low for the installed engine type.