# Formula to determine takeoff thrust

Very very true. For me the A340 is dialed in but I can’t say the same for some others. Fortunately for everyone we just have no choice but to keep practicing 😉

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When I play X-Plane (almost everyday) I use the TOGA system.

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Whoops I did 92 today no joke haha

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Wrong use of N1. You should never exceed 100% N1 on take off unless heavy and at a high and dry airport (Think a fully loaded 747 at KDEN during a summer afternoon). Therefore your N1 will always be lower. Next you have to consider your runway length and load, as well as the weather. I cant give you empirical data but by flying an aircraft often you should be able to figure out relative thrust needed to safely take off. For instance, I often fly the 777-300ER, because of such I know that even at 80% load factor at an airport 500ft MSL and using a runway of 10,000ft I dont need any more thrust than 80% thrust which would be 90% N1. It takes a lot of learning the aircraft model and time flying it to just know how much you need as IF doesnt have a FMC or AT. My recommendation is to just practice taking off in solo in a singular aircraft at different weights and thrust repeatedly. This will allow you to understand how easily your aircraft is accelerating.

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I always take off at N1 90%. Of course if you are heavy or you have short runway, it should be higher.

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Oh, pretty much time practicing

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Okey, I’m on my way to test!💪

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Yeah noted, thanks for the continuous support in several topics of mine

🤣🤣, keeping it always in mind

Yes practicing is the key

That’s a huge helo when flying but unfortunately we don’t have the TOGA system yet in our beautiful game

So maybe I can figure out my own usual % of N1 by practicing 🙏

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Wow, what an expert

Of course it should, thx!🙏👨‍✈️

Not exactly. Whilst we try to minimise engine thrust we use whatever N1 is calculated by take off performance. You’re right that generally the higher the altitude the higher the N1. Also to a point the higher the temperature the higher the N1 but until the engine becomes temperature limited. However, there are more reasons than just hot or high for 100%, or more, N1 being required. However, again, it depends on the specific engine as some may have an N1 limit higher or lower than N1.

For example, the N1 limit on the CFM56 B2 is 107% and there is nothing wrong with using it if necessary.

But the ability of the engine to achieve 100% before becoming temperature limited depends on its flat rated temperature (OAT). Below that temperature you will become N1 limited before temperature limited and vice versa.

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I know, but in IF, I do 93% throttle. It’s sad that there’s no TOGA in IF.

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