747 auto throttle takeoff

[Snuffleupagus 327]

Hello everyone!I am loving the 747 (FS9) but have one thing that I can't figure out. On takeoff, when I use the TO/GA mode, it spools up to 100% n1 when DERATE 2 is selected in the FMC and hits 170kts by the time I get the gear off the ground. It rockets off the runway! I selected the slowest takeoff and climb in the FMC because I didn't need the extra power as I was light. Is it normal for it to takeoff at 100% n1 on the slowest takeoff? I know the 737 doesn't do that. Maybe I missed something in the manual? Anyways, the help would be highly appreciated!

[Tabs 2,790]

This depends on a bunch of factors - what is your gross weight, outside air temperature, elevation etc? The derates aren't static values, they change depending on the conditions/situation.Consider investing in a copy of TOPCAT, it makes it really apparent where the derate calculations come from.

[Snuffleupagus 327]

This depends on a bunch of factors - what is your gross weight, outside air temperature, elevation etc? The derates aren't static values, they change depending on the conditions/situation.Consider investing in a copy of TOPCAT, it makes it really apparent where the derate calculations come from.

Thanks Ryan, I average an elevation of 4500' and very light, ~2hr flights so load is light, temps are about 15C. I am in need of a fuel calculator and I've heard good about TOPCAT, Ill look into it!Thanks again!

[yos233 1]

Thanks Ryan, I average an elevation of 4500' and very light, ~2hr flights so load is light, temps are about 15C. I am in need of a fuel calculator and I've heard good about TOPCAT, Ill look into it!Thanks again!

May I recommend my calculator. I have it on Google Docs, the links are all here.

[Petr Bily 0]

Thanks Ryan, I average an elevation of 4500' and very light, ~2hr flights so load is light, temps are about 15C. I am in need of a fuel calculator and I've heard good about TOPCAT, Ill look into it!Thanks again!

Dear Kyle,TOPCAT is really good software to calculate T/O power. There is of course TO1 and TO2 (derated power), but there is olso possibility to set OAT much higher than it really is. For example 73 degrees of C, etc. Download it and try it. for 747 can be used for evaluation periode.Best regardsPetr

[pcubine 143]

KyleTOPCAT is a very usefull tool for loading, takeoff, and landing information. But it does not take into account the winds aloft when calculating required fuel. On 10-12 hour flights I have seen it be as much as 35000-40000 lbs lower than other fuel calculators which were correct.Michael Cubine