Your Guide to Fuel Burn and Cruising Altitudes in the New 777 Family

^^This. It can help at the 10 or 20% load but it’s by like 50 pounds per hour which means you’ll probably burn more fuel climbing up there than you will save. I’ll discuss more in my guide but at some point you have to balance “this is the best fuel burn” with “this is an actually realistic altitude” so you’re not at FL320 the entire flight.

Sorry for the late reply, but I said 20.1, I hope they can fix it on 20.2.

Also guys is the LR better I am about to do a 15.5 hour flight I’ll have 18 hours of fuel will that be good KSFO-VIDP

Already in air passing FL200 looking good for now hope fuel doesn’t drain j am only going to FL330 tho so I should be fine till morning

You’ll have a ton left over

I can always dumb in the morning I plan on climbing high at points also

Rule of Thumb for B777 optimum altitude for Long Range Cruise (LRC):
578-Weight in metric tons
Source: B777 Emirates Study Guide

I did some tests on the B77W for even altitudes today. Because of the new x5 function I was able to test different speeds as well. Two things I found:

  1. There isn’t actually a level jump from 320 to 360. But 340 is only optimal between about 249-256, hece why easy to skip over.
  2. Optimal cruise speed is not always .84. At above 300t, optimal was FL300@M84, but then the optimal speed drops to .82 to .83, and increases again for very light loads (empty plane basically).

ive seen many 777-300ER’s flying at 40,000 and 41,000 feet on flight radar 24 but that clearly doesnt add up to this chart so how do they do it?

IRL and IF are not the same thing.

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