MD11 flight crew experiences an autothrottle power reduction prior to rotation that goes unnoticed u...

Narrative:

I entered the weight and balance data received from the ACARS into the ops computer. The captain entered the weights and zero fuel center gravity into the FMS. The take off cg in the FMS varied by 1.9 units from the to cg displayed on the du. The acceptable range is plus or minus two units but I had never seen one this close to being out of tolerance. I asked the captain if he was okay with this. He told me he was. This just didn't seem right so I discussed it a bit more and then remembered the training scenario in which the fuel distribution on the aircraft was not the same as what had been used to calculate the weight and balance. Once we had the paper copy of the weight and balance; we confirmed this to be the case and requested a new weight and balance based on the current fuel distribution. On the takeoff roll; I set 1.1 EPR; selected autoflight and announced 'set take off thrust.' the captain replied 'thrust set.' we proceeded to accelerate with a normal 80 KT cross-check. The captain called out 'V1' and 'rotate.' as briefed; I used a slower than normal rotation rate and waited for the aircraft to become airborne. Once in the air; I continued to rotate and immediately had a feeling that something was not right. It felt as if the nose was rising but the aircraft was not climbing. I released back pressure and either held my pitch or possibly reduced it some. The captain called 'positive rate' and retracted the gear. As we continued to climb; things just didn't feel or look right. The FD command bars were commanding a higher pitch than I was holding but I didn't feel comfortable following the bars. The low speed awareness 'foot' was very close to my climb speed. Normally; the climb will settle in at V2 to V2 + 10. But I did not see V2 annunciated on the speed tape. This confused me. I noticed the 'flaps up' indication in the amber low speed awareness bar. At acceleration altitude (about 1;000 ft MSL) the command bars lowered and I reduced pitch to accelerate. We accelerated beyond the indicated flap-retract speed and I called 'flaps up.' shortly thereafter; the GPWS announced 'don't sink' and I noticed a decreasing trend on the vsi. I immediately adjusted pitch to arrest any descent and turned my attention to the power setting. The power was set to 1.1 EPR. I increased power to climb and announced to the captain that climb thrust had not been set. The captain replied that it had been set and it reduced back to 1.1 EPR on its own. Although not company procedure; I can honestly say that while I'm the flying pilot; I virtually always look at the power after the captain has called 'thrust set.' for some reason; I was concentrating on other things and never verified whether take off thrust had been set. Once the power was properly set; the autopilot was engaged and a normal climb had been established; the captain told me he had not seen the normal progression of V1; vr and V2 on the speed tape while accelerating on the runway. He told me V1; vr and V2 were not displayed in the proper order. I cannot confirm this as my attention was focused outside the aircraft.

Original NASA ASRS Text

Title: MD11 flight crew experiences an autothrottle power reduction prior to rotation that goes unnoticed until flap retraction altitude. The Captain as the pilot not flying reported that the FMC generated V speeds reversed their order on the speed tape approaching V1.

Narrative: I entered the Weight and Balance data received from the ACARS into the ops computer. The Captain entered the weights and Zero Fuel Center Gravity into the FMS. The Take Off CG in the FMS varied by 1.9 units from the TO CG displayed on the DU. The acceptable range is plus or minus two units but I had never seen one this close to being out of tolerance. I asked the Captain if he was okay with this. He told me he was. This just didn't seem right so I discussed it a bit more and then remembered the training scenario in which the fuel distribution on the Aircraft was not the same as what had been used to calculate the Weight and Balance. Once we had the paper copy of the Weight and Balance; we confirmed this to be the case and requested a new Weight and Balance based on the current fuel distribution. On the takeoff roll; I set 1.1 EPR; selected autoflight and announced 'Set Take Off Thrust.' The Captain replied 'Thrust Set.' We proceeded to accelerate with a normal 80 KT cross-check. The Captain called out 'V1' and 'Rotate.' As briefed; I used a slower than normal rotation rate and waited for the aircraft to become airborne. Once in the air; I continued to rotate and immediately had a feeling that something was not right. It felt as if the nose was rising but the aircraft was not climbing. I released back pressure and either held my pitch or possibly reduced it some. The Captain called 'Positive Rate' and retracted the gear. As we continued to climb; things just didn't feel or look right. The FD command bars were commanding a higher pitch than I was holding but I didn't feel comfortable following the bars. The low speed awareness 'foot' was very close to my climb speed. Normally; the climb will settle in at V2 to V2 + 10. But I did not see V2 annunciated on the speed tape. This confused me. I noticed the 'Flaps Up' indication in the amber low speed awareness bar. At acceleration altitude (about 1;000 FT MSL) the command bars lowered and I reduced pitch to accelerate. We accelerated beyond the indicated flap-retract speed and I called 'Flaps Up.' Shortly thereafter; the GPWS announced 'Don't Sink' and I noticed a decreasing trend on the VSI. I immediately adjusted pitch to arrest any descent and turned my attention to the power setting. The power was set to 1.1 EPR. I increased power to Climb and announced to the Captain that Climb Thrust had not been set. The Captain replied that it had been set and it reduced back to 1.1 EPR on its own. Although not company procedure; I can honestly say that while I'm the flying pilot; I virtually always look at the power after the Captain has called 'Thrust Set.' For some reason; I was concentrating on other things and never verified whether Take Off Thrust had been set. Once the power was properly set; the autopilot was engaged and a normal climb had been established; the Captain told me he had not seen the normal progression of V1; VR and V2 on the speed tape while accelerating on the runway. He told me V1; VR and V2 were not displayed in the proper order. I cannot confirm this as my attention was focused outside the aircraft.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	976734
Time
Date	201110
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZZ.ARTCC
State Reference	FO
Aircraft 1
Make Model Name	MD-11
Flight Phase	Initial Climb Takeoff
Component
Aircraft Component	Autothrottle/Speed Control
Person 1
Function	First Officer Pilot Flying
Experience	Flight Crew Last 90 Days 75 Flight Crew Total 12000 Flight Crew Type 1000
Person 2
Function	Pilot Not Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 17000 Flight Crew Type 300
Events
Anomaly	Aircraft Equipment Problem Less Severe

MD11 flight crew experiences an autothrottle power reduction prior to rotation that goes unnoticed until flap retraction altitude. The captain as the pilot not flying reported that the FMC generated V speeds reversed their order on the speed tape approaching V1.