A good trim amount for 777-300ER?

I was wondering what a good trim level, cruise altitude, and cruise speed for a flight from DFW to Dubai?

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DFW to DXB is a long trip, I would suggest step climbing from FL320/340/360 or something like that over the course of the flight. Cruise speed for the -300ER is Mach .84, trim can be set around 20-30%.

Question, how much fuel and payload are you carrying?

Max fuel and payload.

You probably don’t need max fuel for the trip, I flew a 14 hr trip in the -300ER and only used 96,000 kgs (212,000 lbs). With a full payload, you probably won’t need more than 115,000 kgs (254,000 lbs) of fuel to make the trip.

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Thank you, but should I apply the trim before takeoff or in-flight?

There should definitely be trim for takeoff and landing. I tend to do 25% for takeoff and 30% for landing

What should I do for cruise?

I tend to go 0 for cruise and only use trim when climbing and descending but I don’t know if that is correct

I normally don’t ever use trim!!!

I would put 40% trim since you are quite heavy.

In cruise you should still use trim. I would keep 20-25% trim throughout the flight (just make sure you can’t see the magenta line!)

Update: 15% trim is good for a cruise but just like everyone else, Trim can be based on preference

My understanding of trim is that we ought to remove the magenta dot in all phases of flight, hence adjusting it regularly up to cruise altitude, then during descent as well. There is no “good” value, the magenta dot shows it is not quite right.
My two cents of course…

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You only need trim 7% for the 77W. Anything higher will give you a tailstrike. For approach expect to trim up to 25%

If you pull hard, no? 😉

Trimming is equivalent to recalibrating your device. As long as you calibrate in a reasonable orientation you don’t need any trim. Trim does absolutely nothing while you’re in cruise with the AP on.

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Even if your device is properly calibrated you almost certainly want some trim. Sure some aircraft you’ll get by just fine, but especially like the MD-11 and stuff, definitely want some trim. Usually not too much is required, and I’m hardly an expert, but it’s definitely not useless.

Also in cruse it definitely does something. Usually the aim would be to get the little pink bar to go away is generally when you have the right amount. Sure it is sum what negligible, and you could definitely get by without it, but it does do something, I promise…

Honestly, I don’t usually use a specific trim percentage as I play around with it until I get the right trim in that moment. There’s a lot of factors that can determine how much of how little trim you use. I see how the trim is affecting my inputs and adjust from there to get that right trim on landing to perfect and grease it in. On takeoff I usually just have a specific percentage though to help with my inputs on rotation. If I were you I’d play around with the trim to see what’s best in the moment for your flight.

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Uhhh it does lol. It pitches you up or down therefor greatly affecting fuel burn and flight time. The magenta line should never be present on the trim button

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That is incorrect, trim currently has no affect on your flight time. I thought I didn’t have to explain this anymore… Yes, it will initially cause you to pitch up or down. However, your aircraft will restabilize in the exact same condition.

The endurance and range of your aircraft will be exactly the same at +100 and -100 trim. It sounds like you’ve never tested it for yourselves but I highly recommend you do.