Fuel usage dynamics Not optimized...

Fuel usage dynamics Not optimized... - Printable Version

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Fuel usage dynamics Not optimized... - Thumper_KJFK AS.381 - 11-10-2009

Hi Crew:

I have sort of a question/problem of sort. Like most of us who fly, I have a ton of Ad-on aircraft Pay and freeware. But right now I am talking about some of the freeware that I fly.
Now that I can see my fuel used on any given flight immediately just before I submit the pirep, I am noticing some of my aircraft will Not have burned much fuel on extremely long flights. See my ACARS data below:

Mach 0.88
Ground Speed 515 knots
Altitude FL 420
Heading 164??
Total Flight Time: 471 minutes / 7.9 hours
Fuel Remaining: Fuel Rem 230,244 Lb / 77%
Data by MYActive AirSource
Origination EGLL Heathrow
Destination RJAA New Tokyo Intl (Narita)
Aircraft Type Meljet B772er JAL
Temp @ Acft 0??F/-18??C
Total Distance 5,174 NM
Dist Remaining 1,212 NM
********
I can't see how I can have that much fuel on board at this point in my flight. When I did land, total FOB 63%.
My question, Is there a way that I can correct the flight fuel usage in the aircraft.cfg. file. Or is there another file that has to be changed? I have some experience working in flight sim aircraft files. But don't know where to start for this problem. I see all sorts of Fuel Data inside the cfg. file. I found I have a number of aircraft with this problem.
Any help on this would be great Smile

Thanks

Re: Fuel usage dynamics Not optimized... - vic365 - 11-10-2009

The FOB number (63%)...did that come from the ACARS or did you actually show that much fuel on board the aircraft at the end of the flight (Aircraft/fuel and payload menu)? Are you using AAS or MyAAS?

Re: Fuel usage dynamics Not optimized... - Thumper_KJFK AS.381 - 11-10-2009

Hi Vic:

Both. the data in myaas is in sync with flight sim data. And to answer your question Yes I have been checking side by side at end of flight. with my own hand written log when I do the math for fuel used in flight.
This anomaly is not new. I just have been living with it. but now I have to Look at the Data on the webb. and it just don't look realistic.

Thanks vic.

Re: Fuel usage dynamics Not optimized... - vic365 - 11-10-2009

Greg, does this anomoly happen with all your aircraft, or just the MelJet 777? What do you have under this section for the 777 in it's aircraft.cfg:

[GeneralEngineData]
//JFDVD
//0=Piston, 1=Jet, 2=None, 3=Helo-Turbine, 4=Rocket, 5=Turboprop
engine_type = 1
fuel_flow_scalar = 0.950 [color=#FF0000]

Re: Fuel usage dynamics Not optimized... - Thumper_KJFK AS.381 - 11-11-2009

Hi again Vic:

I will get back to you tomorrow. I am in the middle of a flight atm and I don't want to go poking around inside Flight sim Folders while it is running. I will be landing around 0500 est. I will check at that time. I also have Pss pro 777. I will take a look. Thanks for pointing out just which area to look in.
The one area i can give you info on is:
[jet_engine]
thrust_scalar= 1.27. I had to change that a year ago. for a bad modulating thrust on take off. It was like riding a bucking bull until I brought up the level from 1.0 to 1.27 for thrust_scalar.

Meljets are the only ones, so far, and One Posky model but that's a 747 Singapore. The reasion i still fly the mel models is the Killer sound sets. Sweet Smile

I will get back to you later, again Thanks .

Re: Fuel usage dynamics Not optimized... - vic365 - 11-11-2009

OK, look forward to hearing back. You can use the Meljet sound sets for the PSS with a tiny bit of Aircraft.CFG tweaking?

Re: Fuel usage dynamics Not optimized... - Thumper_KJFK AS.381 - 11-11-2009

Morning Vic:
OK here is my cfg. settings. I did NOT make any changes yet. Too tired. I make it a point not to go Playing inside files after a flight or when I'm dead on my feet. Smile

I also took a look in 5 other types of 777's by other people. and my MelJet is way out of the ball park, on the low end.
I am home today, I told my dog to wake me at 1100 hrs. I will be back around that time. maybe we can hook up on teamS. or one of the other Voice apps to discuses this. Smile

skype: Thumper_KJFK
Thanks again
Gregory 2hs339

:::Aircraft Type Meljet B772er JAL:::

[GeneralEngineData]
engine_type = 1 //0=Piston, 1=Jet, 2=None, 3=Helo-Turbine, 4=Rocket, 5=Turboprop
Engine.0 = 10.5, -32.6, -8.4 //(feet) longitudinal, lateral, vertical distance from reference datum
Engine.1 = 10.5, 32.6, -8.4 //(feet) longitudinal, lateral, vertical distance from reference datum
fuel_flow_scalar = 0.330 //Scalar for fuel flow efficiency
min_throttle_limit=-0.299927

[TurbineEngineData]
fuel_flow_gain = 0.002 //Gain on fuel flow
inlet_area = 75.95 //Square Feet, engine nacelle inlet area
rated_N2_rpm = 29920 //RPM, second stage compressor rated value
static_thrust = 98000 //Lbs, max rated static thrust at Sea Level
afterburner_available = 0 //Afterburner available?
reverser_available = 1 //Thrust reverser available?

[jet_engine]
thrust_scalar = 1.35

Re: Fuel usage dynamics Not optimized... - vic365 - 11-11-2009

Greg I'm not setup on any voice apps...something I've been meaning to do for some online flights here but not there yet. If you go to http://boeing.com/commercial/777family/ ... oduct.html and check the various "families" (200, 200ER, 300, etc.) you should be able to get some decent numbers to shoot for by adjusting the fuel_flow_scalar entry. I have a round number of 18,000 PPH at cruise, entered into FSNavigator for the 777. Note that it is not divided into -200, -200ER, 300, etc. or engine types. I can get a better number for you...what model is the MelJet? I can do a flight in the PSS and get some numbers...of course, how close the PSS is to reallife is unknown to me.

Re: Fuel usage dynamics Not optimized... - Thumper_KJFK AS.381 - 11-11-2009

Quote:18,000 PPH at cruise, entered into FSNavigator

Hey Vic. A'm I missing something? Where in FSN do you put those numbers in? Settings? on the Cfg. area. I do run FSN but only as a in flight radar moving map/Chart. I find it is a great tool to use as terminal chart. to pull up Nav aid and airport information quickly on the fly. I used to let FSN fly the aircraft a long time ago, but gave that up. I did not like the feel of how that program ran your aircraft. Now I rely on FMC's, FSFK, and FSbuild.

I am Not too picky about how close to the real world #s. I just have to get the #s any where in the ball park. I am really tired of flying from KJFK New York none stop to OEJN Saudi Arabia at Mach 0.87, land and still have 75% of fuel. That sucks, because when I am in a online endurance event I don't fly those aircraft. Unfair advantage not cool.

All I need to do is Plug in some good numbers. I sent an email a long while ago to that group. Tongue

I am just too busy to keep banging my head on walls. what little time I get to my self, is devoted to flying NOT modeling. Now if your talking about Trainz simulator. OK now I model Smile

yeh I know I am all messed up in the head Smile

lol

Ohh That Looks soooo Easy and Way Sweet. don't it Vic Big Grin

[Image: 10418_1164043103644_1304851673_30561974_2344505_n.jpg]

Re: Fuel usage dynamics Not optimized... - vic365 - 11-12-2009

I would try upping that fuel_flow_scalar up tosomething closeto mine and see what happens. I use FSNav for flight planning so the numbers it has need to be pretty close to what the aircraft does (not RW but FS world). You set the aircraft numbers for FSNav in the program, which writes to the aircraft.INI:
X:\Program Files\Microsoft Games\Flight Simulator 9\Modules\FSNavigator\aircraft.ini (or wherever you have it).

Click the PLAN button, select AIRCRAFT and in the drop down menu in the window which opens, pick the aircraft. You will then be shown the numbers that FSN is using for that aircraft...change them after a test flight and click "SAVE". If your aircraft isn't listed click NEW and type in the name and various numbers for speeds, fuel usage etc then click SAVE. The aircraft will now be available in the drop down for flight planning.

[Image: FSN1.jpg]

Here's the aircraft.ini entry for the 777 in FSN:
[Boeing 777]
withoutash=0 Does it have some sort of auto-throttle (yes=0, no=1)
climbspeed=270 I try and find an average for the entire climb for the aircraft
climbfuel=45000 I use a real number based on a climb to a "normal" FL for the AC
climbrate=2500 Again, I try and find a reasonable VS # averaged over entire climb
cruisespeed=300 More like 280 at FL. You enter a seperate number for each FP elsewhere
cruisefuel=18000
cruisealtitude=42000 This should be the AC's Service Ceiling, you enter an FP FL seperately
descentspeed=150 An average over an entire descent
descentfuel=5600 Again, an average over an entire descent
descentrate=2000 Average, again, over an entire descent
fuelmeasure=0 lbs.=0, gallons or kgs. have their own number but you set this in FSN "Settings", so don'tworry about it here.
revision=3

As you can see I'm still using the default numbers which came with FSN, for the 777...it needs some tweaking so I'll have to record numbers on my next 777 flight. You can also create new aircraft in FSN and add numbers...many of mine I've had to add as they weren't included in the INI originally.