Fix fuel consumption of F-15C

[8core]

F-15C uses 2 x Pratt & Whitney F100-229 afterburning turbofans, 29,000 lbf (129 kN) each 2 x 29,000 = 58,000 | mathematically will spend 58,000 lbf, but in real life there limiter is not possible to spend more than 52, 000 lbf, F-15C maximum consumption at low altitude is 52,000 lbf.

In DCS World it consumes 63,000 lbf.

in real life if I have 13,454 pounds and I am consuming 12000 lbf I can fly a little more than 1 hour

In DCS world if I have 13,400 pounds and I am consuming 12,000 lbf I can fly a little more than 30 minutes.

[GGTharos]

Actually it uses a pair of 220's, not 229's.

 

How does the fuel consumption compare to the one recorded in the -1?

[pr1malr8ge]

F-15C uses 2 x Pratt & Whitney F100-229 afterburning turbofans, 29,000 lbf (129 kN) each 2 x 29,000 = 58,000 | mathematically will spend 58,000 lbf, but in real life there limiter is not possible to spend more than 52, 000 lbf, F-15C maximum consumption at low altitude is 52,000 lbf.

In DCS World it consumes 63,000 lbf.

in real life if I have 13,454 pounds and I am consuming 12000 lbf I can fly a little more than 1 hour

In DCS world if I have 13,400 pounds and I am consuming 12,000 lbf I can fly a little more than 30 minutes.

 

Not sure what you're saying, but I just ran a test.. With engine fuel flow set to 6000lb per side, 12,000lb per hour total fuel burn, I'm going through 1,000lbs of fuel per 5 minutes in the game. Giving me 65ish minutes of flight time. Did this test with a stop watch at 3,000ft elevation over the water.. Throttles set at 87.80%

Not sure what you're thinking.. But if you have throttles set at mill power that low then yes you're going to burn more fuel faster. at around 24,000lbs per hour. or 12k per engine per hour. so ~30ish minutes.

only thing I can come up with is you're looking at the fuel flow of one engine thinking its both.

Edited November 14, 2015 by pr1malr8ge

[Sweep]

Actually it uses a pair of 220's, not 229's.

 

How does the fuel consumption compare to the one recorded in the -1?

 

I'll find out in a few minutes...gonna go test that. :)

 

BTW, If anyone else wants a nice read...Chizh posted the 220 performance charts on the DCS site last year.

 

http://www.digitalcombatsimulator.com/en/files/645693/

[pr1malr8ge]

Actually it uses a pair of 220's, not 229's.

 

How does the fuel consumption compare to the one recorded in the -1?

 

According to the -1

 

@sea-level 15*c 360kts the fuel burn on 40,000lBGW 0 drag index [clean airframe] should be 7548lbph

 

Currently the sim is 9100 lbph

 

Not sure if Setting temp in mission planner at 15*c will result in airtemp at 4,000ft to 7*c but if it does the same test reviled a fuel burn of 8800lbph when it should be 6694

 

So the sim is off, a clean airframe in the sim is giving the rough results of a drag index of 60 according to -1.. how ever its nominal truly and Nothing like what the OP is claiming..

 

Personally I still think he's thinking Mill Power should result in 12,000lbph fuel burn for both engines combined when @mill power it's roughly 12,000lbph for each engine. Resulting in 24,000lbph total burn giving him his rough 35mins of flight time.

Edited November 15, 2015 by pr1malr8ge

[Sweep]

Yeah, got similar results testing the low altitude cruise, 40,000lbs*, 360kts (three hundred SIXTY, not FIFTY!) TAS at SL and 4000ft chart.

 

Used default day/month, standard day pressure (744 mm/hg, right?), and standard SL temp (15* C)

 

 

EDIT: Messed up pressure setting because I'm an idiot, track removed.

 

NOTE: I was actually about 250-1000lbs over 40,000lbs, because I had full gun ammo and limited fuel. I'll see about getting more of these done soon-ish. :joystick:

 

EDIT 2 or 3: Does anyone know if a clean airplane (no stores, and no wing pylons) has reduced drag vs a clean airplane + CL/wing pylons?

Edited November 15, 2015 by Sweep
Track removed because stupidity

[DarkFire]

EDIT 2 or 3: Does anyone know if a clean airplane (no stores, and no wing pylons) has reduced drag vs a clean airplane + CL/wing pylons?

 

I believe that if a pylon doesn't have a store mounted then that pylon has zero drag. At least I'm told the Su-27 is modelled in this way so I would assume that it's the same for all the FC3 PFM aircraft.

[GGTharos]

Pylon drag is small, it wouldn't cause a huge difference.

[Sweep]

Pylon drag is small, it wouldn't cause a huge difference.

 

Ok, thx. :thumbup: