Cessna Citation CJ4 Fuel - Range

Hi Flyers, Has anyone else had it where the supposed planes fuel load and range doesn’t match up

not hugely experienced so it could be me being stupid (probably :stuck_out_tongue_winking_eye:) but from my simple calculations.

I was flying it Stansted (EGSS) to Budapest Ferihegy (LHBP)

902 nmi between the 2 (google) Edit (786nmi in SkyVector)
cj4 range is 2,165 nmi (wiki)
I had 69% fuel = 1493.85 Approx I still had to put another 20% to get there, slight tailwind too If I remember correctly

I did AP it for a bit so I could go ■■■■ some food /eat

are my calculations off or something not right ?
hopefully, i can at least learn if its me being silly

Thanks

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I noticed that too. I can barely do 900NM on the CJ4. Something is not right with the performance.

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Same with the Longtitude. None of these jets can go over 900 NM. So the only way to play now is with the unlimited fuel cheat.

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Thanks for the replies

at least I don’t feel SO stupid now :wink:

I’ve been having this issue as well. Was convinced I was doing something wrong but couldn’t figure it out :’)

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I think the fuel flow is 2x what it should be. Doesn’t the 747 have the same problem?

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So, what you can do to adjust the fuel flow and consumption

  • Goto C:\Users\YOURUSERNAME\AppData\Local\Packages\Microsoft.FlightSimulator_8wekyb3d8bbwe\LocalCache\Packages\Official\OneStore\asobo-aircraft-cj4\SimObjects\Airplanes\Asobo_CJ4
  • Back up the engines.cfg
  • Open the engines.cfg
  • Edit high_fuel_flow to 1700
  • Edit fuel_flow_max to 2200
  • Save and Enjoy

Reading up on http://jetav.com/cessna-citation-cj4-performance-specs/ i think these values are halfway useable. At least it feels more realistic.
Of course you can use values that you see more fitting. I guess they should be even lower to fit the real world.

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How much range did that give you?

I mean. I didn’t fly the full range. But on cruise I now get something about 220 gph fuel consumption.
Which LNM calculates to about 1700nm. But the calculation highly depends on speed and whatnot.
Which is pretty close to the specified 2000.

1700NM is much better than 900NM

Both of the Citations are busted. I tried to make a flight from Fort Worth to Vegas on day one in the Longitude. I took off with half a tank and had to make an emergency landing at 480nm when I suddenly realized that I was almost out of fuel. Inexcusable that the PREMIUM DELUXE aircraft that I paid for doesn’t even have the proper fuel mileage. How did this get past beta testing?

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The Longitude was not available for beta testing. It’s first appearance is with the Premium Deluxe release. That makes you the beta tester and if you want the range fixed, then send a report to zendesk and apply the workaround suggested by dga711 until a fix is released.

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Not really, considering the fact that the CJ4 has the same problem. Anyone with enough brain cells to rub two of them together would probably figure out to check the other Citation as well. But that point is moot since the CJ4 WAS in the beta and fell through the cracks with such an obvious issue. Remind me again what the point is in filing a report when they should have already been aware of this before the game even launched? Like, seriously, all it would take is someone at Asobo testing an internal build and cruising in the jet and function testing it for 30 minutes to see that it is wrong.

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The more people that report an issue using Zendesk, the more attention it’s going to get from Asobo. Anytime you find something wrong, send in a report. Just because a problem exists at launch doesn’t mean Asobo is not aware of the problem. Asobo has stated they will continue to fix problems after the launch and bring new features to the sim.

If dga711 is an alpha insider and has a workaround, that tells if this was a known issue.

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Hi guys ,

I’ve been flying for the last 2 days the Cessna Longitude (CJ4) and i was able to fly with VNAV and LNAV. Flightplan loaded before start flight, not on FMC yet.

Full tanks for a 02:10H flight to check fuel consuption.
Distance 934 nmi ,
Altitude 38000 FT.
Speed 250 IAS.

Everything goes fine till i have a suprise after 782 nmi. My FUEL TANKS ARE EMPTY.
I think this airplane should do around 3500 nmi. I did 4 attempts and same results.
Any sugestions ?

Thanks.

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see this post: Cessna Citation CJ4 Fuel - Range?

I tried the fix that dga711 suggested, but my ITT temps were out of sight.

I found that editing the engines.cfg
fuel_flow_scaler = 1 to a value of 0.5
made the fuel flow much more realistic in the CJ4.

Leave the high_fuel_flow and fuel_flow_max at their default values. The ITT temps stay more realistic and the endurance of the plane is a lot better. At FL400 i was burning about 1200lbs total an hour. I read an article that said they were shy of 1100lbs. This is acceptable to me.

I tried to do the same thing for the Longitude. The files are different for it. The fuel tanks incorrectly match the size of the CJ4. That’s the main issue with the Longitude, but I can’t find how to change it at this time.

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I didn’t have the problem with ITT or noticed it. But if the scaler value works better, then thats good. I was scared to touch it.

Yeah right now we can’t edit the stuff on premium planes cause its encrypted in the fsarchive files.

Before edit the cfg file, you were burning 1200pph? In each engine or total?
Because I fly at FL440 match 0.762 (223 ias) burning 1440pph in each engine. I was reading and article about a pilot writing of his flight with the cj4 saying that it was burning 775pph at fl450

I am burning about 1258pph after edit TOTAL. Before edit I was burning about 2600 pph TOTAL. After scaler edit, you will find she burns about 600-700 pph on each engine or 1200-1400 pph TOTAL. An article I read reported 1040 pph total fuel flow at FL450 with 425 KTAS.

Just for clarity, the max fuel of the plane is 5762lbs. So thats 2881lbs in each tank. If you’re burning 1440pph on each engine, you’ll burn through that tank in less than two hours. Especially considering you’ve probably burned about 25% of it during climb. With the edit, you will have burned much less on climb. I climbed @ 240 kts until mach .64 and then maintained .64 until cruise altitude of FL400. Than sped up to .74
When cruising at about 58-60% N1 I was burning ~629pph each engine. ~1258pph total.

Here is a link to the article where i got the info:
https://www.flyingmag.com/pilot-reports/jets/all-grown-cessna-cj4/

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