747-400 / 8 cruising issue?

@StormyAviation I always use Flap 10 for cruise with the 747. It helps it stay flat. Nothing goes wrong nor is it a bad thing

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For the 747s flaps in cruise will actually increase your range dramatically! Yes it not realistic but it works in IF.


It was definitely the weight of your aircraft. What was your load?

Never use that much positive trim when heavy it will cause a stall and no way to get out of it.

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Never knew this, don’t fly the 747 much though.

I’ve used it in all kinds of weights, it shouldn’t affect whether or not it will stall. If you’re stalling at a certain altitude, it’s better to descent at that point.

I usually don’t use positive trim on takeoff because it likes to stall out.

Then you must be flying way too slowly, either rotate faster or climb slower. Autopilot should handle everything during climb.

I’m not sure If it is a issue though.

I transitioned from @CPT_Colorado to @Tsumia’s idea (was that me who told you?) about using 60% trim during the flight with no flaps needed. Using the fuel fpltoif (simbrief) gives you, and the trim helps you get to your destination with much fuel left over, don’t use the amount suggested in hours in game for the 747.

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Oh sorry, my total load was like 300+k?

How long would I stay at those altitudes for?

I would say step climb to your cruise.

Until you have gained enough speed.

The Boeing 747 has horribly inaccurate physics (weight to lift and lift to drag ratios) which makes it use much more power and burn much more fuel to maintain speed than how the plane works

I use 10 degrees flaps because it decreases angle of attack and drag therefore reducing required power to maintain speed, try that out. I know it’s not realistic but then again the physics of the plane are even more unrealistic

Finally someone who understands why I do this.

In real life, this is true. But what is also true is that IF itself is not 100% realistic and that experienced pilots know the plane they are flying and what it can handle and what makes it perform better. Experienced IF 747 pilots like me know the plane and know that keeping at least 10 degrees of flaps deployed all throughout the flight will make it perform significantly better meaning the angle of attack is significantly less and the required fuel to maintain speed is much less therefore you save a TON of fuel. And pilots trying to save fuel is very realistic.


Infinite flight’s Boeing 747 family has quite high rotation speeds compared to other planes, even with 10 degrees of flaps deployed the rotation speed for 80% load is 170-190. Anything lower and you risk stall after takeoff, which is a very common cause of crash in IF and IRL.

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@DeerCrusher crushed me to pieces when I said this. (Pun was not intended)

It’s all in the trim and what Simbrief says

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I tend to fly the 747 quite often in IF and I’ve never experienced this issue. I never have needed to use flaps mid-flight though…

The 747 tends to cruise between M.82 up to M.92 at the very most.

I recall a topic before regarding flap issues of some sort and a irl 744/748 pilot did say that the characteristics of the plane are pretty accurate.

The 747 doesn’t tend to climb very high, if you’re at MTOW you’ll start off at FL280 or 290 and maybe go to FL380 or 390 but that’s probably the highest you’ll go under heavy weights. If you’re lighter you’ll be higher.

I use simbrief.com a lot and it seems to give accurate amount of fuel and step climbs necessary for a flight. Though that works best for the 744 from my experience. The 748 ain’t quite right in terms of fuel.

If you’re pitch is around 5 degrees (maybe a little more/less) that’s fine.

Though I’m pretty confused as to how F10 improves the 747’s flight characteristics. You should have more drag and be burning fuel much quicker…

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Thanks for the info, ya I was pretty heavy and I always cruise at M0.85 it’s just my go to lol

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