How much power is needed to move aircraft from stationary to taxi speeds?

Because I was cleared for immediate takeoff, I wouldn’t want to risk getting ghosted for taking my time lining up with the runway and then spooling up even if I don’t stop at any point. I was stationary behind the hold short line when tower cleared me. I increased throttle to 30% N1 but I think ATC will still ghost me for being too slow.

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Slowly increase power to get you moving and then throttle back enough to keep you moving.

You will not be ghosted for taxiing too slow, but when called for immediate takeoff, look at the traffic and the distance to runway, then think if you need to really really hurry up or take it a notch slower. It’s better to taxi slow than fast. Normal taxi speed is 15-25kts. Use 10% power or N1 - 30

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Your N1% varies based on your aircraft load. In general 40% N1 is the max for taxi thrust around terminals.

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I was using 11% PWR from stationary but in my opinion I believe the controller shouldn’t have cleared me for immediate takeoff. From what I understand immediate takeoff is most appropriately used when an aircraft didn’t stop behind the hold short line and gets T/O clearance while rolling.

If you get cleared for immediate takeoff, just go into your map quickly and and look at how far the traffic is away from crossing the threshold. If it’s quite near, 50% power and don’t stop, if it’s a little farther away, you can carefully lineup and takeoff without stopping.

This command can be used anytime. If the controller tells you to takeoff, s/he can see that there is space, you also have to see it and get off the runway asap. If you don’t think you’ll make it just send a stand by followed by a I’m sorry. The controller should understand

Wouldn’t I get warned for not following instructions?

That’ll be unrealistic, I did that and wasn’t too happy about it. Had to end my flight because I was disappointed with my takeoff.

Just do it as in real life: once cleared for immediate takeoff turn on your lights, enter the runway, line up and accelerate without stopping (rolling departure) in order to clear the runway as soon as possible. The ATC will be grateful to you as well as another Captain which will avoid to go around on short final.
Blue skies :)

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on the 737 breakaway thrust is normally 30 to 35% N1, that is sufficient to commence taxi. Once at the desired speed about 27 % should be sufficient to maintain that speed. You certainly shouldn’t be using power settings of 40% N1 or more when taxi-ing.

In some aircraft like the 747 if light you’ll actually start moving slowly once the brakes are release as there is enough thrust even at idle to get you moving.

Shouldn’t be ghosted for that. N1 speeds vary tbh, the 757 needs about 50% just to get moving,… Thats not accurate as its in need of a rework.
As others have said, aim for upto 30% max then throttle down a bit :)

But if I’m too slow, it’s not my fault that the arriving aircraft has to go around right?

well, at the end of the day, the controller makes the judgement call that there is enough room for you to squeeze in a takeoff before the aircraft behind you lands. If you follow said help above, and are still ghosted, you’d be able to back up your defense.

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In the 737 I do 25% to 10 knts ground then back it to 15% till my taxi speed and keep power at 2% and cut it so the plane slows to 10knts ground in a turn.

Typically the speed of taxing onto the RW, does not make too much difference as long as it is reasonable, it is the time it takes to come to a complete stop, and begin rolling again that causes an issue and the potential for a go around.

To those of you who say you shouldn’t use more than 40% N1 and whilst I agree that it may not always be necessary Boeing consider up to 60% N1 to be standard taxi thrust in the 737NG.

Just so you know.

That;s interesting. Where did you hear that from?

Couple of years back when we started doing single engine taxi after landing. The engine had to be at or below taxi thrust for 3 minutes before shutting down. The company sought clarification from Boeing (or might have been CFM actually) what they considered to be taxi thrust and that was the answer.

When in a heavy, I would initially throttle up to 40% to start rolling, and then quickly throttle back to 30% and lower, after you reach 6 - 10 kts. All this depending on aircraft size and weight.

The ATC should take the size of your aircraft into account, and understands it will take a little time to start rolling. But…don’t stop, obviously; roll towards lineup and as soon as you can, go! I sometimes see pilots in panic lining up with 20 kts, dramatically overshooting the center line and taking off from the lawn. Not necessary.

As long as you don’t stop, and make a serious effort to be quick (without being unrealistic), you’ll be fine. Remember, IFATCs are not in the business of ghosting; they only ghost when they have to.

A go-around is not desirable, but certainly not the end of the world. And yes, it’s not your fault, nor is it your problem.

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I use 50% power till 5 knots then slowly roll back and keep it between 5-10 percent. That is just me though. I once spent 1 hour establishing power and taxi speeds at an airforce base lol.

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