B747-400
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 240; Flight Crew Total 5500; Flight Crew Type 3500
Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Other / Unknown
Flight Crew Became Reoriented
Company Policy; Human Factors
With our new pre-departure takeoff procedures; where we DO NOT brief takeoff performance; the flying First Officer DID NOT brief the takeoff performance. This is our new SOP. At the start of the takeoff roll; the Captain selected TO/GA; the throttles advanced normally with THR REF annunciated on the PFD; and the EPR settled on 1.37; with 90 % N1. I mentioned from the secondary relief seat that that was not enough thrust. The three First Officers all noticed immediately that this was not enough thrust for a normal reduced thrust takeoff. The flying First Officer immediately grabbed the performance data printout; read the thrust requirements to himself (1.46 EPR and 96 % N1; and advanced the throttles to the proper setting for our takeoff at roughly 820;000 LBS with flaps 20. The cause of the initial improper setting was that the flying First Officer; when selecting a reduced thrust temperature; inadvertently selected 54 degrees; which resulted in 53 degrees being displayed on the upper EICAS for the reduction. The correct number was 39 degrees from the performance data. This error happened as he read across on the performance data line and saw: 39 54/67/77; where 54 really means 154 KTS for V1; 67 means 167 KTS for rotation; and 77 means 177 KTS for V2. The two relief pilots; myself included; didn't notice it since there was no performance brief; which is oddly now our new SOP. What saved the day was the years of experience on the airplane; 14 for me alone (10 as an instructor); and knowing what normal takeoff EPR and N1 look like.
B747 Relief Pilot describes a takeoff; initially using an incorrect assumed temperature; producing a 90% N1 indication while 96% was required. Takeoff performance was not briefed per recent changes to SOP.