Evan,
The distance between 0 speed and rotation start is 2300m.
The speed at which rotation started is 191kts.
That gives you an average acceleration of 4.08 kts per second, which is a quite typical lower bound for a big twin jet at MTOW (be it the structural MTOW or the climb-gradient restricted MTOW, for example in high'n hot situations no matter how long the runway your MTOW is limited by the second segment climb gradient with an engine inop. The climb gradient is very strongly correlated to the thrust/weight ratio, and the acceleration IS the thrust/weight ratio). Even with a reduced take-off thrust (again, if your lowest thrust is limited by the second segment climb gradient with an engine out, so with a heavy airplane there is only so much you can go down with the take-off thrust regardless of the runway length)
I must warn, however, that the distance is extremely sensible to small changes in the acceleration. 3.58 kt/s (just 1/2 kt/s less) would give you 300 meters more of distance.
The airplane ate another 586m (to a total of 2866m) in the 5 seconds between the rotation start and the actual lift off.
And then it sould was likely a few hundreds of meters more since lift-off to 35ft.
And then add more distance for the reduced acceleration between V1 and 35ft had an engine failed at V1.
With that performance, the computed take-off distance (from zero speed to V1 with both engines, engine failure, from V1 to 35ft and V2 with one engine) for the real thrust setting used would clearly be several hundred meters past 3000m. Runay 09 is some 3600m long. So we have an approximate match.
Additionally:
The pilot elected to compute an optimized take off thrust, got an assumed temp of 36 C, and printed out that output for reference.
With all that in mind, I don't see any reason to believe that the pilot used full thrust instead of the calculated reduced thrust. It could be, but it's not like anything in the performance can make you think so.
The report will tell.
The distance between 0 speed and rotation start is 2300m.
The speed at which rotation started is 191kts.
That gives you an average acceleration of 4.08 kts per second, which is a quite typical lower bound for a big twin jet at MTOW (be it the structural MTOW or the climb-gradient restricted MTOW, for example in high'n hot situations no matter how long the runway your MTOW is limited by the second segment climb gradient with an engine inop. The climb gradient is very strongly correlated to the thrust/weight ratio, and the acceleration IS the thrust/weight ratio). Even with a reduced take-off thrust (again, if your lowest thrust is limited by the second segment climb gradient with an engine out, so with a heavy airplane there is only so much you can go down with the take-off thrust regardless of the runway length)
I must warn, however, that the distance is extremely sensible to small changes in the acceleration. 3.58 kt/s (just 1/2 kt/s less) would give you 300 meters more of distance.
The airplane ate another 586m (to a total of 2866m) in the 5 seconds between the rotation start and the actual lift off.
And then it sould was likely a few hundreds of meters more since lift-off to 35ft.
And then add more distance for the reduced acceleration between V1 and 35ft had an engine failed at V1.
With that performance, the computed take-off distance (from zero speed to V1 with both engines, engine failure, from V1 to 35ft and V2 with one engine) for the real thrust setting used would clearly be several hundred meters past 3000m. Runay 09 is some 3600m long. So we have an approximate match.
Additionally:
The pilot elected to compute an optimized take off thrust, got an assumed temp of 36 C, and printed out that output for reference.
With all that in mind, I don't see any reason to believe that the pilot used full thrust instead of the calculated reduced thrust. It could be, but it's not like anything in the performance can make you think so.
The report will tell.
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