Your Guide to Fuel Burn and Cruising Altitudes in the New 757

REWORKED 757 CRUISE PROFILE

20.3 is here! The reworked 757 is beautiful and a dream to fly. Here are some fuel profiles to help you get the best fuel economy.

How to Read This Guide

An orange cell signifies a cruise altitude a little too high for that aircraft at that weight that carries smaller fuel penalties.

A green cell signifies a cruise altitude appropriate for that aircraft at that weight going East, maximizing fuel economy.

A blue cell signifies a cruise altitude appropriate for that aircraft at that weight going West, maximizing fuel economy.

A grey cell signifies a cruise altitude that is too low for that aircraft at that weight that may or may not carry a small or large fuel penalty.

Fuel Capacity is simply the maximum fuel that can be loaded onto that aircraft.

Game-Estimated Maximum Flight Time is the flight time that Infinite Flight tells you when you fully fuel your aircraft.

Theoretical Maximum Flight Time is the flight time calculated from these numbers that is theoretically possibly, waiving all IFR altitude rules and reserve fuel rules.

Practical Maximum Flight Time is the flight time calculated from these numbers that takes into account a 90% passenger and 75% cargo load (75% cargo load only for the Freighter), IFR altitude rules, and reserve fuel rules.

Flight Profiles are the ideal sequences of cruise altitudes for an aircraft at different loads.

Disclaimers

Disclaimer I : Numbers are from solo testing and have not been tested live yet.

Disclaimer II : The 757 has speed dip, meaning it sits at M 0.79 when set to 0.80. Measurements were taken with the AP at 0.80.

Disclaimer III : To keep it simple, I only took measurements every 10% load. If there were huge drops in fuel burn over those 10% I tried to take them into account when determining the climb profile.

Disclaimer IV : I am assuming linear rate of change of fuel burn between 10% increments. This is likely not the case, but it should be close enough.

Disclaimer V : Numbers in charts are in pounds. Works all the same for kilograms just different numbers.

757-200

Figure 1 - 757-200 Fuel Burn Chart

Fuel Capacity : 76,968 lbs or 34,912 kg

Game-Estimated Maximum Flight Time : 10hr 17m

Theoretical Maximum Flight Time : 11hr 41m

Practical Maximum Flight Time : 9hr 53m (Eastbound) | 9hr 49m (Westbound)

Flight Profile (East): FL310 (100%-41%), FL390 (40%-21%), FL410 (20%-0%)

Flight Profile (West): FL300 (100%-71%), FL320 (70%-41%), FL400 (40%-0%)

Key Takeaways

The 757 burns fuel predictably and reasonably. No need to pack a ton extra.

The 757 is not the most efficient at standard altitudes. You don’t need to avoid FL330-FL380, however, as the numbers aren’t that different.

The 757 is forgiving. Even if you pick the wrong altitudes, it won’t bite you.

Enjoy 20.3!

67 Likes

Nice topic Andrew!

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Bookmarked, thanks a lot!

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Nice one :)

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Bookmarked! Love it!!

Curious about the reason for the big jump between 40% and 50%

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It’s due to the design of my testing, which is based on empirical data. All the mid-weight options (30-70 ish) net very similar fuel burn amounts, and so there just so happens to be a breaking point around 40-50 where higher altitudes are very very slightly favored.

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Oh, interesting!

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Yup, and if you don’t want to make that big jump while flying, I get that, and that’s why I left the rest of the numbers up there so anyone can read, interpret, and make their own decisions on how they want to fly.

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Very nice guide , I’m loving theses new guides being made for the 757.

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Wow FL310 then FL390 and nothing green in between 😂

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Quite odd yes but once again just based on numbers, you could step through 330, 350, 370 and all will be fine.

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Geez Andrew, future 757 pilot or something??

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No I understand I just thought it was funny from the 777 one that is out

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Isaac on the IFC? What is life.

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Andrew Wu with the math 😳😳😳

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Yeah, I can read a number off a screen and do basic functions, big math moment.

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On the 777 there is a short window where 340/350 are most efficient. I have done the testing for it myself actually.

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I’m doing testing myself as well. BTW something else I found: .85 more efficient than .80 lol, might use that if I use a 757 as a substitute aircraft for a long haul.

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Oh that’s cool, I was just using 0.8 bc it’s the standard speed

Yeah I sometimes check other speeds a bit as well. The old 757 was the opposite lol, when it’s light most efficient speed is like .72

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