777-300 Long-Haul Flight Struggles

My favorite plane in IF is the Boeing 777-300ER, but I struggle with having enough fuel to travel long distances that I know the plane can handle in a real-world setting. For example, I recently ran out of fuel on approach to Brisbane (YBBN) after a 14 hour journey from LAX (40K feet at 0.86 mach). I take this real-world flight many times per year, and can attest that we did not in fact run out of fuel on approach.

My climb to 40K feet is abnormally gentle in the 777W so as to save fuel, and even that doesn’t work. Further, at cruising altitude, the aircraft stays at fuel throttle just to maintain speed, regardless of the set speed. It just feels underpowered.

Does anyone else experience this? Is this something that the developer team should look into?

Did you step climb? Fl400 is very high for an initial cruise. This means N1 would be high and so would fuel flow. This would counter any benefit of thinner air. Secondly, try flying at m.84/5 instead.

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Did you step climb up? That can use some needed fuel. Were your tanks full?

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First of all, don’t cruise at 40K feet in a 777-300ER 30 minutes into a 14 hour flight. When beginning your flight, be sure to Step Climb to ensure maximum fuel efficiency.

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I have got that problem too. It was a big problem for me when I was doing Doha - Auckland. But then I reduced my speed to M0.84 (which is the best cruising speed in my opinion) and I landed safely in Auckland.

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The specified cruising speed in a 777-300ER is around M0.84, and it is a low cruiser, you usually start somewhere around FL300 if you’re heavy and end at around FL360 at the end of cruise.

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Initial cruise of 34K feet, then after ~30 mins of cruise, climbed at 500 feet/min to 40K.

Perhaps my speed has been too fast for this airframe.

Still too early. You would only go to Fl400 towards the end of the flight, and if you had a high load you may not even do it at all. Secondly, did you make use of trim?

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Thanks all! I appreciate the quick feedback.

Hey, Mark! Check out this Flight log from the exact flight you’re doing. Notice the first altitude is FL310. Each screenshot begins at the next altitude… notice the first climb is nearly 4 hours after leveling at cruise.

FL310:

FL330:

FL350:

FL370:

Note the times and try this. You should have much better success. Good luck!

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Thanks. I will implement the above suggestions in future flights.

I did not make use of trim. How does this affect climb/cruise? Does it reduce the required thrust?

Essentially proper trim = less fuel consumption. If you see the trim button, there will be a little pink line next to it. This indicates the trim you should be using at the stage of your flight!

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This can reduce the required N1 to hold that altitude and relieve a great deal of pressure in the climb. Check out this tutorial:

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A good ‘one size fits all’ to start with is around 30% for the 787/777. Use that as a base and adjust as needed for your flight until you get a better understanding (:

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Agh now I feel like I’ve been a flying Fred Flintstone for the past three years…

Still learning after all this time!

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Aren’t we all! That’s the fun of it. Good luck! 🙂

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MaxSez: Now this Topic and most of the comments are a fine example of what the Forum was designed for! The examples and commentary are first rate and ansewer the mail technically. Well Done All Concerned!

Duty Experts there a lesson to be learned between the lines here. Keep mouth shut if you don’t have the experience and full knowledge on the subject at hand. Personal layman’s experience and pontificating don’t get it!

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MaxSez: The “Good Peanut” Knows Quality when he reads it…

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