Lets talk 'baseRCSmodifier='

[+dtmdragon 2,704]

Based on some discussions in the old TW forums with TK, the 0.2 baseRCSmodifier value for the stock F-16A Netz in the game (note however TK has mistakenly assigned the F-16C baseRCSmodifier value to the F-16A Netz as explained later in this post) and other topics I have read I have come to the following conclusions:

1, The game engine does not correctly calculate an objects RCS. Instead it simulates it by using the size of the aircrafts hit-box as defined by its .lod to decide at what distance an aircraft is detected by a radar after taking into account that radars power etc.

2, The baseRCSmodifier value is a multiplier that reduces the size of the aircrafts hit-box to simulate any RCS reducing measures that aircraft has. This in effect reduces the range the aircraft can be detected on radar.

3, The games hit-box size RCS method is basically accurate for an aircraft with NO RCS reducing technologies as far as the game is concerned.

So to work out the baseRCSmodifier value for an aircraft with a reduced RCS, we need to work out what percentage its real world RCS is of its hit-box game decided RCS.

 

Knowen (or educated guess?) of RCS values of aircraft WITH RCS reduction measures:

F-5E: 3 m2

F-16C: 1.2 m2

Gripen: 1.0 - 1.2 m2

F-18E: 0.75 m2

Rafale: 0.75 m2

Eurofighter: 0.5-0.75 m2

B-2: 0.01 m2

F-35: 0.01 - 0.005 m2

F-22: 0.01 - 0.001 m2

F-117: 0.001 -? m2

RCS values of aircraft with NO RCS reduction measures:

F-16A: 6.0 m2

F-15C: 10.0 m2

 

To get the hit-box game generated RCS of an aircraft we have to work it out by comparing the physical size of the aircraft with non RCS reduced aircraft we know the RCS of. For size comparison we can use the F-16A 6m² at one end of the scale and the F-15A 10m² at the other.

For example I would give the F-18F Super Hornet an estimated hit-box RCS of 9m² based on its physical size. Its real world (reduced) RCS is 0.75m² so the baseRCSmodifier value is 0.75/9= 0.083

BaseRCSmodifier=0.083

This was the same calculation done by TK in a (now gone) third wire forum topic to get the baseRCSmodifier=0.2 value for the F-16C that TK thinks should be used on the F-16A as well. (I say this as the real world F-16C has RCS reducing measures not the F-16A.) And as I said TK has gone on to use that baseRCSmodifier=0.2 figure for the stock F-16A Netz in the game.

Same calculation for the F-35:

Real world RCS of 0.005m² hit-box RCS of 7m² so 0.005/7=0.00071

baseRCSmodifier=0.00071

F-22:

Real world RCS of 0.001m² hit-box RCS of 10m² (as the F-22 is roughly the same physical size as the F-15) 0.001/10=0.0001

baseRCSmodifier=0.0001

The hardest part is deciding where an aircraft fits hit-box RCS size wise. I collect diecast scale model fighter jets so I was able to compare all the aircraft in my examples to each other to decide how they compared size wise and what size their hit-box RCS would be in the game. Knowing the hit-box size of the F-16 equates to a 6m² RCS in the game and the hit-box size of the F-15A equates to a 10m² RCS in the game gives you a pretty good idea and scale to use.

Edited June 9, 2020 by dtmdragon

[+Menrva 4,200]

Admins, if possible, let's pin this thread. It's useful info.

[MigBuster 2,884]

2 hours ago, dtmdragon said:

(I say this as the real world F-16C has RCS reducing measures not the F-16A.)

Unlikely because Have Glass looks to have started around or before 1983 and there are still quite a few advanced A models in service today.

 

http://www.f-16.net/forum/viewtopic.php?f=2&t=5243&p=275164#p275164

 

 

[Wrench 9,848]

oh, hell yes this is getting pinned!!

DONE!!

[+dtmdragon 2,704]

7 hours ago, MigBuster said:

Unlikely because Have Glass looks to have started around or before 1983 and there are still quite a few advanced A models in service today.

 

http://www.f-16.net/forum/viewtopic.php?f=2&t=5243&p=275164#p275164

 

 

F-16A as delivered and excluding MLU or ADF upgrades

[MigBuster 2,884]

6 hours ago, dtmdragon said:

F-16A as delivered and excluding MLU or ADF upgrades

hmm well very early A models maybe - technically new A model production went up to the mid to late 1990s and there was some commonality between the A/C after a point - quite likely some had RCS reductions and others didn't but a tad difficult to discern.

 

 

[+EricJ 4,245]

22 hours ago, dtmdragon said:

 

For example I would give the F-18F Super Hornet an estimated hit-box RCS of 9m² based on its physical size. Its real world (reduced) RCS is 0.75m² so the baseRCSmodifier value is 0.75/9= 0.083

BaseRCSmodifier=0.083

 

Where would I put BaseRCSmodifier on the _DATA.ini?

[Wrench 9,848]

in the DetectSystem section

ala F-117:

[DetectSystem]
VisualBlindArc=5L,6,7L
VisualRestrictedArc=5,7
MaxVisibleDistance=1000.0
HasRWR=TRUE
RWRMinFreq=1.0
RWRMaxFreq=20.0
RWRCanDetectCW=TRUE
BaseRCSModifier=0.0000005
HeatSignatureModifier=0.0010

 

[+EricJ 4,245]

18 minutes ago, Wrench said:

in the DetectSystem section

ala F-117:

[DetectSystem]
VisualBlindArc=5L,6,7L
VisualRestrictedArc=5,7
MaxVisibleDistance=1000.0
HasRWR=TRUE
RWRMinFreq=1.0
RWRMaxFreq=20.0
RWRCanDetectCW=TRUE
BaseRCSModifier=0.0000005
HeatSignatureModifier=0.0010

 

Thanks!

[+dtmdragon 2,704]

7 hours ago, MigBuster said:

hmm well very early A models maybe - technically new A model production went up to the mid to late 1990s and there was some commonality between the A/C after a point - quite likely some had RCS reductions and others didn't but a tad difficult to discern.

 

 

I am sure you are right but for the purposes of this topic (and along with the F-15A) it gives us a scale to work with when figuring out the hitbox area RCS the game creates. If that makes sense.

Edited June 10, 2020 by dtmdragon

[Stratos 3,192]

The MiG, 21, 23, 25... etc, need no RCs update?

[+dtmdragon 2,704]

18 hours ago, Stratos said:

The MiG, 21, 23, 25... etc, need no RCs update?

No as for an aircraft with no real world RCS reduction measures the game engine generated .lod 'hit box' size based RCS is correct.

Edited June 14, 2020 by dtmdragon

[Stratos 3,192]

That's what interested me. Thanks a lot!