CFG problem

I have this aircraft [PROJECT OPENSKY BOEING 747-300 Combi for FS2004 only/ KLM-Royal Dutch Airlines]

I've discovered why it's like a brick to fly - the cfg is in the nose = wing_pos_apex_lon= 0.000

I've tried -20.000 & others but it remains stuck in the nose.

I see the default 747 is -50.............

Does anyone have a number that will sort this out for me ?

Thanks.

I would try and find a freeware aircraft of similar type and see if that cfg works, not forgeting to save the the the [fltsim.0] entries and contact points and lights sections.

Sometimes you may also need to air file from the one you copy off.

Also make sure you backup the original first.

I have this aircraft [PROJECT OPENSKY BOEING 747-300 Combi for FS2004 only/ KLM-Royal Dutch Airlines]

 

I've discovered why it's like a brick to fly - the cfg is in the nose = wing_pos_apex_lon= 0.000

I've tried -20.000 & others but it remains stuck in the nose.

 

I see the default 747 is -50.............

Does anyone have a number that will sort this out for me ?

Thanks.

The wing position is as it should be, as is the CG in the [WEIGHT AND BALANCE] section. The problem is that there is only one station_load entry and there's nothing in it:

station_load.0=0.000000,0.000000,0.000000,0.000000

If you replace this station_load entry with the ones from the default 747 you should see an improvement.

EDIT: On second thought, now I've had a good look at these FDE's, I'd get the Posky 747-300 base model: https://www.flightsim.com/vbfs/fslib.php?do=copyright&fid=115967 and just install the KLM livery into it.

Poskey uses xml coding for a lot of things. The default 747 doen't use any xml. So, I don't think a cfg and air files alone will fix his problem. But I could be wrong. NEWs at 11.

Chuck B

Napamule

First, did you mean CoG and not cfg?

If so, without posting your [WEIGHT_AND_BALANCE] and [Fuel] sections at a minimum from the aircraft.cfg file that you are using it will be near impossible to provide a solution for you. Every longitudinal, horizontal, and vertical point specified in the aircraft.cfg file is in relation to the reference datum from the [WEIGHT_AND_BALANCE] section of the aircraft.cfg. The Posky B743 I have shows a reference datum of:reference_datum_position = 97.0, 0, 0. The first number is the longitudinal offset, and if I remember correctly it is from 1/4 of the wing mean root chord. If the wing root chord is 20 feet then 1/4 of that would be a point 5 feet aft of where the leading edge of the wing meets the fuselage. So, Posky has their reference point 97 feet forward of the 1/4 wing root chord. You said your file shows wing_pos_apex_lon= 0.000, this means that your wing apex is 97 feet forward of 1/4 wing root chord, that's not correct. The longitudinal position of everthing, fuel tanks, elevator, tail, station loads, etc etc is in relation to whatever the reference datum is set at. If I had to take a wild guess, I would say that maybe all your fuel tanks are too far forward, making the plane nose heavy. this is the [fuel] section from my B743:

[fuel]

Center1 = -97.000, 0.0, -4.0, 11847.0, 3.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)

LeftMain = -102.000, -35.0, -4.0, 12538.0, 3.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)

LeftAux = -108.500, -52.0, -3.0, 5761.0, 3.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)

RightMain = -102.000, 35.0, -4.0, 12538.0, 3.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)

RightAux = -108.500, 52.0, -3.0, 5761.0, 3.0 //Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)

fuel_type = 2 //Fuel type: 1 = Avgas, 2 = JetA

number_of_tank_selectors = 1

electric_pump=1

Good luck

Good morning.

Yes I meant CoG.

The figures I have are these:

[WEIGHT_AND_BALANCE]

reference_datum_position= 0.000, 0.000, 0.000

empty_weight_CG_position= 0.000, 0.000, 0.000

max_number_of_stations=50

empty_weight=446847

empty_weight_roll_MOI= 13155743.000

empty_weight_pitch_MOI= 22600873.000

empty_weight_yaw_MOI= 25151035.000

empty_weight_coupled_MOI= 1000.000

max_gross_weight=833000

CG_forward_limit= 0.000

CG_aft_limit= 1.000

station_load.0 = "170.0, -19.0, -2.0, 8.0, Pilot" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.1 = "170.0, -19.0, 2.0, 8.0, Co-Pilot" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.2 = "1700.0, -83.5, 0.0, 0.0, Crew" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.3 = "5440.0, -27.0, 0.0, 0.0, First Class" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.4 = "5780.0, -65.0, 0.0, 0.0, Business Class" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.5 = "7140.0, -50.0, 0.0, 8.0, Upper Deck" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.6 = "10710.0, -91.0, 0.0, 0.0, Coach 1-7" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.7 = "18020.0, -119.0, 0.0, 0.0, Coach 8-18" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.8 = "23800.0, -160.0, 0.0, 0.0, Coach 19-34" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.9 = "18000.0, -52.0, 0.0, -6.0, Forward Baggage" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

station_load.10 = "6000.0, -123.0, 0.0, -6.0, Aft Baggage" //Weight (lbs), longitudinal, lateral, vertical positions from datum (feet)

[fuel]

Center1 =0.000, 0.0, -4.0, 19431.0, 3.0

LeftMain =-5.0, -35.0, -4.0, 16660.0, 3.0

LeftAux =-11.5, -52.0, -3.0, 500.0, 3.0

RightMain =-5.0, 35.0, -4.0, 16660.0, 3.0

RightAux =-11.5, 52.0, -3.0, 500.0, 3.0

fuel_type = 2

number_of_tank_selectors = 1

electric_pump=1

[airplane_geometry]

wing_area= 5500.000

wing_span= 196.000

wing_root_chord= 23.000

wing_dihedral= 6.998

wing_incidence= 2.000

wing_twist= -0.994

oswald_efficiency_factor= 0.830

wing_winglets_flag= 0

wing_sweep= 37.500

wing_pos_apex_lon= 0.000

wing_pos_apex_vert= 0.000

htail_area= 1470.000

htail_span= 72.750

htail_pos_lon= -17.167

htail_pos_vert= 0.000

htail_incidence= -4.000

htail_sweep= 37.500

vtail_area= 1060.000

vtail_span= 37.121

vtail_sweep= 45.000

vtail_pos_lon= -16.500

vtail_pos_vert= 6.083

elevator_area= 326.800

aileron_area= 225.200

rudder_area= 229.900

elevator_up_limit= 20.751

elevator_down_limit= 15.313

aileron_up_limit= 31.513

aileron_down_limit= 31.513

rudder_limit= 17.189

elevator_trim_limit= 19.167

spoiler_limit= 25.783

spoilerons_available= 0

aileron_to_spoileron_gain= 3.000

min_ailerons_for_spoilerons= 11.459

min_flaps_for_spoilerons= 0.000

-----------------------------------

Can you spot the problem ?

Thanks,

Terry.

yes, but i think the easiest fix would be to find the default Posky 747-300 aircraft.cfg and then just copy your [fltsim.xx] entries into that. The aircraft.cfg you are using has all the station loads aft of the wing, your horizontal tail longitudinal entry, htail_pos_lon= -17.167, and vertical tail longitudinal entry, vtail_pos_lon= -16.500, has them not even aft of the main wings trailing edge. Here is a link for the Project Opensky archives where you can download their default FDE files, I think that would be your easiest and quickest fix. Good luck

http://www.poskyarchive.com/boeing/

Many thanks....I'll give it a whirl!

I must ask.....what's that aircraft in your picture. It looks fun !

For what it's worth, I have a Posky VC-25A (Air Force 1 version of B747). The .air file has a section number 1204 with an entry "Main Wing Center of Lift ...." value of 0.0. Most .air files don't have a 1204 section.

If the OP has a similar .air file, then the CG values might make sense.

Regard,

JerryH

For what it's worth, I have a Posky VC-25A (Air Force 1 version of B747). The .air file has a section number 1204 with an entry "Main Wing Center of Lift ...." value of 0.0. Most .air files don't have a 1204 section.

If the OP has a similar .air file, then the CG values might make sense.

Regard,

JerryH

Edit: Some day I'll learn to send only once!!

It appears to me that the reference datum position is at the nose, and all station loads are scattered behind that for the length of the plane.

 

Normally the COG position should be at around 1/3 the wing chord (average). But since this line in the Weight and Balance section:

 

empty_weight_CG_position= 0.000, 0.000, 0.000

 

says it's right at the nose, that won't work. Try editing this line along with the wing positions to put all of them back to the logical COG?

Tom, the reference datum he has is reference_datum_position=0,0,0. The empty weight cg is the offset from the reference datum. A reference datum of 0,0,0 will put the reference datum on the centerline of the fuselage at 1/4 of the wing root chord. I think the wing chord of a 747-300 is about 30 feet, so 1/4 is about 7.5 feet, so the reference datum is centerline vertical, centerline horizontal, and 7.5 aft of where the leading edge of the wing intersects the fuselage. Since the empty weight cog is not offset at all it will be in the exact same place.

From the MS FS2004 SDK, the definition of the reference datum: Offset (in feet) of the aircraft's reference datum from the standard Flight Simulator center point, which is on the centerline ¼ chord aft of the leading edge.

From the MS FS2004 SDK, the definition of the empty weight cog:Offset (in feet) of the center of gravity of the basic empty aircraft (no fuel, passengers, or baggage) from the Reference Datum Position.

Perhaps you had in your mind the fact that the default FDE's from Posky and the default MS b747 have the reference datum of something like 97,0,0, in which case a empty weight cog of 0,0,0 would be way up forward.

BTW, love your cal classics site, have tons of them in my FS9 folder

[WEIGHT_AND_BALANCE]

reference_datum_position = 97.0, 0, 0

empty_weight_CG_position = -100.0, 0, 0

station_load.0 = 3740, -42.5, 0.0, 14.8, Business Upper Deck

station_load.1 = 1360, -9.0, 0.0, 4.0, First

station_load.2 = 4080, -41.0, 0.0, 4.0, Business

station_load.3 = 14620, -75.5, 0.0, 4.0, Economy 30-38

station_load.4 = 16320, -111.5, 0.0, 4.0, Economy 44-53

station_load.5 = 24140, -151.0, 0.0, 4.0, Economy 54-69

station_load.6 = 0, -133.0, 0.0, -2.0, Aft Cargo

station_load.7 = 0, -42.5, 0.0, -2.0, Fwd Cargo

[fuel]

Center1 = -97.000, 0.0, -4.0, 17164.0, 0.0

Center2 = -195.000, 0.0, 9.0, 3300.0, 0.0

LeftMain = -87.000, -22.0, -1.0, 12564.0, 0.0

LeftAux = -112.500, -50.0, 2.0, 4482.0, 0.0

LeftTip = -138.500, -87.0, 5.0, 1322.0, 0.0

RightMain = -87.000, 22.0, -1.0, 12564.0, 0.0

RightAux = -112.500, 50.0, 2.0, 4482.0, 0.0

RightTip = -138.500, 87.0, 5.0, 1322.0, 0.0

[contact_points]

point.0 = 1, -19.000, 0.000, -15.000, 5181.102, 0.000, 2.042, 70.000, 0.500, 3.500, 0.900, 11.000, 11.000, 0.000, 240.000, 280.000 // Nose Gear

point.1 = 1, -110.583, -5.000, -17.000, 3574.803, 1.000, 1.917, 13.000, 3.000, 2.500, 0.900, 12.900, 14.900, 2.000, 240.000, 280.000 // Main Center Gear - Left

point.2 = 1, -110.583, 5.000, -17.000, 3574.803, 2.000, 1.917, 13.000, 3.000, 2.500, 0.900, 13.100, 15.400, 3.000, 240.000, 280.000 // Main Center Gear - Right

point.3 = 0, -102.083, -17.000, -15.000, 3574.803, 1.000, 1.917, 0.000, 1.620, 0.150, 0.741, 12.900, 14.900, 2.000, 240.000, 280.000 // Main Wing Gear - Left

point.4 = 0, -102.083, 17.000, -15.000, 3574.803, 2.000, 1.917, 0.000, 1.620, 0.150, 0.741, 13.100, 15.400, 3.000, 240.000, 280.000 // Main Wing Gear - Right

point.5 = 2, -148.000, -105.000, 7.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 5.000, 0.000, 0.000

point.6 = 2, -148.000, 105.000, 7.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 6.000, 0.000, 0.000

point.7 = 2, -189.667, 0.000, -2.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 9.000, 0.000, 0.000

point.8 = 2, -9.167, 0.000, -5.750, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 4.000, 0.000, 0.000

point.9 = 2, -226.000, 0.000, 48.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 8.000, 0.000, 0.000

point.10= 2, -106.400, -69.500, -5.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 9.000, 0.000, 0.000

point.11= 2, -76.300, -39.167, -9.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 9.000, 0.000, 0.000

point.12= 2, -76.300, 39.167, -9.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 9.000, 0.000, 0.000

point.13= 2, -106.400, 69.500, -5.000, 787.402, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000, 9.000, 0.000, 0.000

Hello,

Thanks for everyone's help, before I go further!

I copied your data, napamule2, but it's grossly overweight & the CoG is 3/4 back & on the left.

tiger1962 suggested this;

"EDIT: On second thought, now I've had a good look at these FDE's, I'd get the Posky 747-300 base model: https://www.flightsim.com/vbfs/fslib...ght&fid=115967 and just install the KLM livery into it. I will have a go the the Podsky FDE."

I've decided not to pursue that & to ditch this aircraft. I'm installing some Mike Stone aircraft into a new simmer's machine & his 747sp is a great one to fly so I'm going to put that into my FS9 too. I really like the 727-200 in the Condor livery as well - my goodness how that shines!!

I appreciate the suggestions from everyone & thanks again.

Terry.

The reference_datum_position is the position of the 0,0,0 position in the plane's model (MDL) file. While most authors place this at the COG position, some place it at the nose or other locations. When placed at the nose the reference_datum_position or the empty_weight_CG_position must have a value that places one of them at the COG point or the COG will be at the nose.

That said, I loaded this 747 MDL file into ModelConverterX and the grid confirms that this plane's 0,0,0 point is at the COG position. As downloaded (and as stated above) this plane has a single line for it's station loads:

station_load.0=0.000000,0.000000,0.000000,0.000000

which means either the payload is included in the empty weight value, or it has no payload by default. Any payload you add there will be added at the 0,0,0 point (COG).

But the OP has a very different station load listing, with all loads placed behind the COG (negative values in the longitudinal direction). This means this plane will be very tail heavy and fly poorly.

Hope this helps,

Tom,

In your above post, I've often wondered why there are so many zero's in entries, not just the weight but in other things, I would have thought 0.0 would be enough or do they do that to make it look more technical lol?

Microsoft used '0.000000' on everything they put out. This was because the air file wrote some of the sections in cfg. For FS9 and FSX Accel I only use 3 zeros (for decimal values) on everything ('0.000') which makes it easier to align lines and edit/compare/match decimal values. But 6 zeros or 3 zeros will work the same. And you CAN use 1 zero ('0.0'), or 2 zeros ('0.00') but you will 'miss' errors of punctuation, etc (ie: '0.30' -vs- '0,30 -vs- '0.3,0' ' ) line in cnt pts, lights, smoke, etc. Neatness counts! And if values don't have the '.000' 'extension' I add them! That's just me being anal (what else is new).

Chuck B

Napamule

I rarely touch the contact points but I have done when needed of course, as for the rest I recently got an aircraft and whoever wrote the cfg was zero crazy.

Any line that needed a zoro he went over the top, I backed it up first then edited it just doing one zero and the aircraft flew fine, after a few more trouble free flights I kept the edited version.

On a side note, if anyone wants any zero's I have some they can have. :)

Quote: '...if anyone wants any zero's..'

I got zero negative numbers - plumb out! Have you got any of those laying around you don't need? :)

Following on from this, I recently downloaded a few aircraft from the same model builder but instead of zero's in his cfg's he had very big spaces between sections in the cfg.

I know the sim doesn't read a space but when I was looking in them I was scrolling most of the time to get through.

Anyway I deleted them and made the cfg a lot shorter, so if anyone wants any spaces I have a few of those too.

Hang on to them, spaces can be pretty useful.