Is there a problem with the B777-300ER fuel consumption, because I was trying to use it for a long flight, but when I got to cruising altitude it said I had 8 hours less fuel then I put.
When climbing, your aircraft uses a lot of fuel to get to cruise. This all depends on speed, VS, and weight of the aircraft.
Either you loaded up the aircraft very heavily or you have a strong headwind.
There’s a ton of reason why this might happe.
Daniel14 made a great point, climbing requires fuel, so the higher your VS speed the faster you’ll need to go.
HiFlyer also made a good point, what’s your Weight like?
There is not a fuel problem with the B77W. The fuel is accurate. What will mess you up is climbing to a higher altitude with too much weight or going faster than what the normal cruise is for the aircraft. If you are going faster than M86 you are going too fast and burning too much fuel.
What’s your VS when climbing? I think the optimal speed at cruise btw is somewhere around M0.81-M0.83 (someone correct me if I’m wrong)
Check this tutorial by our awesome friend Brandon, it will explain how to save fuel whilst climbing and in cruise. It seems as you have climbed way too fast or in an inefficient manner and you lost a couple tons of fuel during climb.
To save fuel during the cruise stage of flight I suggest checking it this guide to step climbing by DeerCrusher, it is very crucial to step climb especially in those very long flights that are excess of 7 or 8 hours.
Another great guide by DC for improving aircraft endurance and extending your range. It speaks about the importance of using Trim, etc…
In my opinion, you did something wrong while in the Climbing Stage of flight, as the 777 let alone the 77W can do flights that are 17, 18, 19, even more than 20 hours if you play your cards right and do everything correctly.
I hope the links I provided above can help you, they really did help me when I got started doing Ultra Long Hauls when Global was initially released.
Hope this helps,
Just use Simbrief and there will be no more problems:)
Referencing all of the above should solve your problem. Keep in mind that wave drag increases exponentially the faster you go at transonic speeds, which will significantly increase fuel burn for little gain in speed. So if you are cruising faster than the manufacturer’s published cruise speed, there’s probably a lot of fuel to be found by slowing down.
My vs was 2500 and my load was 100% so it makes senses why it would use a lot of fuel climbing. Thanks for the help
Make sure when setting your fuel, passengers, etc. the screen doesn’t have read text saying “> MTOW”. This means you’re over the “Maximum Take-Off Weight” for that aircraft.
100% load is definitely going to be too heavy for that climb. However, if you set the load to less, then that VS should be ok.
We actually just finished doing some testing on the 77W to get the proper simbrief fuel perf(ormance) factor. For example, if Simbrief says you should load 279.3 and your burn should be 267.4 for a given flight at a given Zero Fuel Weight (ZFW) then you should actually burn between 266.9 and 267.9 (we try to allow for +/- .5/500lb) In our testing, we found it to be a -20 fuel factor/perf factor. This was all tested out on multiple transoceanic/transpolar long haul flights. We base weights on max passengers per airline
In simbrief, we take infinite flight’s weights from the sim, and put in the passenger configuration for the airline we’re flying-For example, Emirates’ 3 class (V1) 77W’s carry a total of 354 passengers. We then base the MZFW on IF’s numbers (354 pax plus max cargo) rather than the default simbrief numbers.
Lastly, we follow the real world routes as best possible including the full Departure/Arrival/ILS etc.
Here’s a typical climb profile that’s used at virtualBlue in conjunction with simbrief numbers. I hope it helps you out.
Takeoff is done at reduced thrust (if possible depending on the runway), followed by thrust reduction at 1000-1500’ with a pitch down for speed then vertical speed is set as follows:
Takeoff to thrust reduction:
Whatever the proper takeoff pitch angle gets for V/S, hold this til ~1500’
Thrust reduction to 10K:
-At 1500’ reduce your thrust to “climb power” usually 85-90% N1 (based on aircraft of course)
-simultaneously pitch down allow speed to build to 250kt, engage autothrottle at 250kt
-Resume 2000-2300’ V/S at Climb power in other words-don’t let the N1 climb up to takeoff settings or higher! (you can engage your AP V/S if you like at this point.)
-At 10K, disengage your autothrottle/speed again and lower your V/S to allow speed to build to the simbrief climb profile speed (don’t forget to turn off your landing lights!) then re-engage your autothrottle at the climb speed (310KT for the 77W) and then raise your VS back up-at this point, realistically, it should be somewhere between 1500-2000fpm and the higher you go, the lower your VS should be (weight depending of course)
FL200-Top of Climb
-Once thru FL200, dial your VS back again to between 1500-1200 fpm.
-Passing FL280, note your Mach (should be .84 roughly but you may have to adjust based on temp/winds etc) and again, reduce your VS speed down to 1200-1000 fpm
-At top of climb, settle in for the ride and ensure your cruise Mach is as planned in simbrief.
-At top of climb, your Fuel WILL LIKELY be lower/behind what simbrief is quoting you, but you will equalize in the cruise and start noticing your fuel numbers catching up.
Pic below is the simbrief climb/cruise/descent profile selections:
What website is that?
It happened to me before on my 18hr flight from SGBL to VHHH
I had to stop over Nairobi to refuel lol
when climbing I always use N1 to decide my VS, for example on a rather regular load on the A320 my climb pwr would be around 79%, and I just keep it like that and adjust the VS to keep the speed, with slight increases as we get higher up, just like they would in real life.
Keep in mind, the airplane will get lighter as it burns fuel. When I was flying a long haul, at first it was 4 hours less than what I put, but when I arrived, I had 1 hour of fuel to spare.
I had an issue too, from KLAX to Moscow the 777-300ER had to use full tanks. I don’t think it uses fully tanks on that trip in real life.
SimBrief is a great tool. However, take care to type in all the details correctly.
I have run out of fuel before multiple times due to entering the info incorrectly.
Either that, or the physics in IF might not be the same as IRL, in which case the fuel amounts from SimBrief will be incorrect.
I fly the B777-300ER a lot and do actually spend 80% of my time flying in it. I have been flying a lot of long haul flights with it and don’t really have too much of a problem. Personally even if I do load the plane with 477 passengers, full cargo and 65,236kg of fuel in the right and left fuel tank I can still fly up to 18 hours without fully loading the fuel tanks. (Route is KMIA - VHHH or VHHH to KMIA, even further than VHHH to KJFK). I just climb at a rate of around 2500m/s max and at a speed of 240kts while I am below 10000ft and then increase speed to around 320kts and then when I am at cruising (I normally fly 3100ft throughout the whole flight) I just stay at Mach 0.84.
Though it is something to get used to so take your time, it takes a lot of experience!
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