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The never ending debate of flightmodels...


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Posted (edited)

The never ending debate that the flightmodel in Falcon AF is different then the flightmodel in Falcon OF.

 

To answer that i compared the FM-datas for the F-16C-52 (PW229 engines) in both cases.

( i haven´t added each single number and value, becuase that would have ended in a huuge list here)

 

 

Result:

 

INPUT MASS AND GEOMETRIC PROPERTIES:

 

AF:

19635 # Empty Weight (lbs)

300 # Reference Area

7162 # Internal Fuel

 

OF:

19635 # Empty Weight (lbs)

300 # Reference Area

7162 # Internal Fuel

 

ANGLE OF ATTACK AND SIDESLIP LIMITS:

 

AF:

40 # AOA Max

-8 # AOA Min

30 # Beta Max

-30 # Beta Min

9.0 # Max G

190 # Max Roll

250 # Min Vcas

900 # Max Vcas *

420 # Corner Vcas

8 # Theta Max

3 # Num Gear

 

 

OF:

40 # AOA Max

-8 # AOA Min

30 # Beta Max

-30 # Beta Min

9.0 # Max G

190 # Max Roll

250 # Min Vcas

850 # Max Vcas

420 # Corner Vcas

8 # Theta Max

3 # Num Gear

 

 

PHYSICAL DATA:

 

AF:

27.00 # CG Loc

47.00 # Length

32.0 # Span

2.5 # Fus Radius

4.5 # Tail Ht

 

OF:

27.00 # CG Loc

47.00 # Length

32.0 # Span

2.5 # Fus Radius

4.5 # Tail Ht

 

BASIC AERODYNAMIC COEFFICIENTS:

 

Num Mach:

 

AF:

0 0.2 0.3 0.4 0.5 0.6 0.7 0.9 0.95 1.0 1.05 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.9 2.0 2.1

 

OF:

0 0.2 0.3 0.4 0.5 0.6 0.7 0.9 0.95 1.0 1.05 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.9 2.0 2.1

 

Alpah Breakpoints:

 

AF:

-8 -4 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 14.5 15 15.5

16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

31 32 33 34 35 40 55 70 90

 

OF:

-8 -4 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 14.5 15 15.5

16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

31 32 33 34 35 40 55 70 90

 

Lift Coefficient CL:

 

Table Multiplier = 1.0 (AF & OF are the same)

 

*here the the endless values* see attachement*

 

 

Drag Coefficient CD:

 

AF & OF same with Table Multiplier 0.66666, but

 

comparing all values from Mach 0.00 to Mach 2.10 (in 0.10 step) AF has slightly higher values

in the mach-tables (* Mach table - see above Lift Coefficient CL as example)

 

 

SIDE FORCE DERIVATIVE CY-BETA:

 

AF & OF Table Multiplier = 1 *both have same values

 

*here the the "endless" values - see attachement*

 

 

PROPULSION DATA

 

AF & OF uses 1.0 Thrust Multiplier and 1.0 Fuel Flow Multiplier based on

same Mach Breakpoints

(0 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.05 1.1 1.15 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.2)

and Altitude Breakpoints

0 10000 20000 30000 40000 50000 60000 75000

 

references are

 

THRST1 - THRUST AT IDLE (THROTL = 0.00)

THRST2 - THRUST AT MIL POWER (THROTL = 1.00)

THRST3 - THRUST AT FULL AB (THROTL = 1.05)

 

the tab values (* see attachment*) are absolutly the same for AF and OF

 

 

FUELFLOW:

 

Here OF differs from AF. Comparing the listed datas....

 

OF:

 

fuelFlowFactorNormal 0.941

fuelFlowFactorAb 2.26

minFuelFlow 868

fuelFwdRes 480

fuelAftRes 480

fuelFwd1 2772

fuelAft1 2330

fuelWingAl 550

fuelWingFr 550

fuelFwdResRate 22.2

fuelAftResRate 22.2

fuelFwd1Rate 22.2

fuelAft1Rate 22.2

fuelWingAlRate 6.66

fuelWingFrRate 6.66

fuelClineRate 20.0

fuelWingExtRate 33.3

fuelMinFwd 400

fuelMinAft 250

 

AF:

 

fuelFlowFactorNormal 0.726 ****

fuelFlowFactorAb 2.06 ****

minFuelFlow 868

fuelFwdRes 480

fuelAftRes 480

fuelFwd1 2772

fuelAft1 2330

fuelWingAl 550

fuelWingFr 550

fuelFwdResRate 22.2

fuelAftResRate 22.2

fuelFwd1Rate 22.2

fuelAft1Rate 22.2

fuelWingAlRate 6.66

fuelWingFrRate 6.66

fuelClineRate 20.0

fuelWingExtRate 33.3

fuelMinFwd 400

fuelMinAft 250

 

we already see slight variations, but furthermore it appears that OF has uses a more sophisticated way

of calculating Fuelflow structured in Mach- and Altitude Breakpoint.

After having a mail exchange with Mav-Jp (the maker of HIFI EM-charts) he has confirmed that OF uses

a "more accurate" fuel consumption (that´s a while back over frugals forums though....but i remember)

 

 

 

ROLL DATA:

 

Alpha Breakpoints:

 

AF & OF is same

 

-10.000000 0.000000 10.000000 20.000000 25.000000 30.000000 90.000000

 

 

 

DYNAMIC PRESSURE BREAKPOINTS

 

Num Qbar:

 

AF & OF is same

 

0.000000 100.000000 200.000000 300.000000 400.000000 500.000000 2000.000000

 

 

 

RCMDMX - PEAK ROLL RATE

 

Coefficient =1

Rate Table for alpha -10, 0, 10, 20, 25, 30 and 90 AF & OF are the same

 

0.000000 171.820007 243.410004 257.730011 257.730011 257.730011 229.089996 0.000000 214.770004 286.359985

 

300.679993 315.000000 315.000000 286.359985 0.000000 171.820007 243.410004 257.730011 257.730011 257.730011

 

229.089996 0.000000 71.589996 143.179993 157.500000 157.500000 157.500000 128.860001 0.000000 60.000000

 

93.070000 107.389999 107.389999 107.389999 107.389999 0.000000 30.000000 42.950001 57.270000 57.270000

 

57.270000 28.639999 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000

 

 

LIMITERS:

 

OF: (difference in AF marked with ****)

 

17 # Number of limiters

# Type Key Values

#

# Neg G Limiter

0 0 250 -3 100 0

# Pos G Limiter (Cat I)

3 1 15 9.0 20.4 7.3 25.2 1 **** AF: 15 20.4 25.2 9.0 1.0

# Roll Rate Limiter

0 2 15 1 25 1

# Yaw Alpha Limiter

0 3 14 1 26 0

# Yaw Roll Rate Limiter

0 4 20 1 360 0

# Cat III Command Type

0 5 350 18 420 15

# Cat III AOA Limiter

1 6 16

# Cat III Roll Rate Limiter

2 7 0.6

# Cat III Yaw Alpha Limiter

0 8 3 1 15 0

# Cat III Yaw Roll Rate Limiter

0 9 20 1 180 0

# Pitch and Yaw Control Damper

3 10 0 0.3 15 0.85 50 1 **** AF: 0.0 15.0 50.0 0.30 0.85 1.00

# Roll Control Damper

3 11 0 0.6 15 0.85 50 1 **** AF: 0.0 15.0 50.0 0.60 0.85 1.00

# Command Type

1 12 15

# Low Speed Omega

3 13 0.01 0.1 40 0.8 60 1 **** AF: 0.01 40.0 60.0 0.10 0.80 1.00

# Stores Drag

0 14 0.9 0.0001 1 0.000283

# Cat III Max Gs

1 16 6.5

# AOA Limiter

1 17 25.2

 

 

*****ERGO: ********

 

Except the more sophisticated fuel consumption in OF, and the slightly higher Drag tables for AF under same

Mach- and Altitude breakpoints, and few differences in the Limiters, the flight models are pretty much the same.

 

Surely higher drag tables - even just slightly - in AF require a little bit more "disciplined hand" to conserve your energy and may play a role if it comes to things like timing your Gs, but the difference is really small.

 

What i can NOT confirm - and dont know - is if the Joystick response (curves) in OF act the same way as they do

in AF. Basically if the input is processed in the same way.

 

Often you hear from many that the flightmodels are different, but this shows, they are not. Gfx and sound also can "set you off".

 

I hope this helps !

 

PS: ..i was bored, and had that quick idea to make this quick over 2 coffees :)

Edited by A.S

[sIGPIC][/sIGPIC]

Posted

The fuel flow in OF is actually a big difference in performance between the two sims in AF you can fly in full afterburner for much longer than OF because of this. Differences that you did not mention are the ground handling in AF has momentum modeled so it takes longer to stop with a full load etc. And also the FCC in inflight refuelling mode for AF dampens the controls which is what it does. Although none of these features are in the tables above it is worth mentioning also whats missing from both is the requirement for trim. IRL eventhough its FBW the F-16 still requires trim like on the VRS Superhornet so to get the ultimate FM would be:

1/ LPs FM and modes

2/ OFs fuel flow

3/ VRS Superhornets trim

4/ wind/turbulence(maybe not FM but atmospheric effects)

[sIGPIC]2011subsRADM.jpg

[/sIGPIC]

Posted

I was only focusing on the f-16c-52bk.bad(dat) files which defines the FM characteristics.

Other differences surely excist.

[sIGPIC][/sIGPIC]

Posted
All FM of Falcons are bad.. so now is witch is the less bad of the two..

 

thats why you should never fly it. !! really dont !! :music_whistling:

  • Like 1

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