Suggestion for database, data supply
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But your thrust inputs, from what I can understand, are extrapolated from missile speed vs time.
No.
1. If Epsilon is small than 24° in the moment of launch the thrust is 3500 kg (~7720 lbs) for 45 seconds.
2. If Epsilon ε>=24 in the moment of launch thrust is 3500 kg (~7720 lbs) to 24 second then 2000 kg (~5510 lbs) to 55 seconds.These two options are RL life data, not extrapolation. This is THE THRUST vs TIME which you seek. I do not understand you…
I did a small correction in thrust, I scaled down 7700 lbs to 7200 lbs to get the closer result in speed vs time and speed vs distant curves in both cases. Why? Because Cl and Cd values likely not match with real values. You won’t find even the stuff that you can download. For field operators it is not important these coefficents. They are not engineers… Instead playing with Cd I set a bit smaller thrust.
if we can get the THRUST vs time data, that would be EXACTLY what falcon requires. And it would be as accurate as we could get the missile.
As I see you do not understand even the problem. We have the thrust char. What have to be calculated or experimented? The Cd (for drag) and Cl for available G. But you have to understndd what is worth and what is not. My tweaks are very close to RL measurements as you can see even the big difference in target altitude. (Strong effect of air density.) Of course if you have plenty of free time you can set up Cl and Cd curves. You can set these curves that you do not have to scale down the thrust, but you will get back the good time vs dist. and time vs. speed comparin with RL data. Only question, does it worth to spend hundreds of hours to get only a ~3-4% better model…?
Regardless how you master of modeling you can’t avoid that Falcon data structure prevents model the different settings of RL system. I think here the epsilon dependency of applied thrust control, different pursuit methods. This is just the two main issues concerning on the specific system. You can’t model the different fuel consumption for different thrust char - epsilon dependency, you can’t model the separation of booster stage and changed Cl, Cd, you can’t model the small effect on thrust of amibent tem. and pressure, Ect.
In short. You can sped lost of time to refine the model, but IMHO you can’t do much better model concerning on time vs speed and time vs distance. These are the most important paramteres combining with warhead modeling, and available Gs and guidance (pursuit method.) You can make a better model for available G modeling but in Falcon’s world - as in RL - but how frquent event to evading a SAM about +10 km altitude? Literally 0. —> 6.8 maximum G, in 99,9% of cases this will be good. Of course the effect on drag by control surfaces are not modeled - AoA is litarally always 0 in Falcon for missiles - but you cannot find exact RL data. You can see only the oputput, what I have show. What is available. It is not important why.
Is is clear now?
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Was clear the first time… I guess I’m too tired to even understand what I’m reading… guess I’m WAAAAY past my bedtime
Check you PM
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I made an additional test against and escaping target. Because of small eng range, I cannot perform by the same way as I did. On ~20k alt SA-2 launched a missile from ~17 nm. I turn back and I set a very slight climb profile to simulate the nearly constant Epsilon.
Result.
You can see that deacceleration profile can be “attached” to previous test.
1. Peak speed is small than in RL.
2. Deacceleration is bigger then in RL at peak speed.Cd likelyl too big above M2.3-2.5.
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TONS of original releted materials here.
I suggest that you should contact the developer of SAM Simulator - he had done a tremendous job of going through the original materials and interpreting them into a working flight model. (though not in 3d world)
http://simhq.com/forum/ubbthreads.php/topics/3202301/SAM_Simulator.html
EDIT
I just saw you already did that.
My bad. -
SA-3. First of all, some ACMI files that shows serious problems.
http://www.mediafire.com/?wqpj91n2bpp2i
What are the main problems?
- Engagement range is very small comparing with RL value. RL value is 25 km.
- Because of small engagement range and default guidance values even a non maneuvering and slow target is impossible in some situation. Three missiles required to shoot down an An-2 (!).
- Aganist the F-16 the result is slightly different, 2nd missile hit the non maneuvering target. 2nd missile worked because the different relative position of launch position and target.
- In a simple dive any fighter is impossible target.
- I uploaded an ACMI with tweaked guidance value using An-2 and F-16 either. Only problem that I cannot test the effect of different guidance with longer range against maneuvering target.
My conclusion. As long as engagement distance is so undermodeled SA-3 is useless. It is not a real threat. Even thrust and weight values are tweakable they cannot be tested and verified. I have to skip SA-3 and work on another missile.
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Molny this is excellent work. I certainly hope to see your changes in the DB one day.
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Good observation.
This is very sad. SA-3 was quite dangerous in all F4 versions I have played during last 7? years I think. Does it mean BMS4 uses some very old 1998 db entries?
Luk
Edit: I had the oportunity to watch only your AN-2 tapes in Tacview (my 4-5 year old Laptop GPU started to overheat in last days, so I can not run accelerated 3D now, new machine on the way ). Just watched DB entries for AN-2. RCS is 0,9 of the F16 value, but the plane is “stealth”. It is the reason 2 missiles missed I think.
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Stealth flag controls the day/night operations as I know. If the AN-2 would be stealth by RCS it could not be targeted as long as radar is not able to detect. On other video you can see when I changed the guidance values in dat file the first missile destroyed the An-2 in 100% same situation where the 1st and 2nd missed the target. I can exctrat elevatopn profile of missiles in both cases if you wish.
Sadly, it seems to me that engeagement distance is hardcoded in exe. I tried to tweak eng. distance by all method I know, without any sucess.
My next target will be SA-5. It is very, very inaccurate as well as SA-2. The biggest problem for SA-5 also the much smaller eng. distance as RL and bubble dist. Even I can increase the bubble, I cannot tweak the eng distance. Even I can tweak the max. engagemen distance it is a big progblem that different guidance method and thrust profile cannot be modeled, and AI likely will engage low-medium al. targets outside the effective kinematic range of the missile. (<10k alt with +30-40 nm).
Today I will share some material. -
First observations about SA-5.
- The current guidance model is useless. Missile is not able to hit even a straight flying target, regardless it speed, and altitude.
- The current aero data range is small, coefficients are defined only Mach 4. In RL peak speed is far beyond Mach 4…
- Blast radius is about the same as SA-2’s missile has even it is much stronger. In RL SA-5’s missile warhead contains about 37k (!) srapnel comparing to ~8k of SA-2’s missile.
Here are some ACMI files. You can see the guidance problem from different distance. The two other cases will be used for showing the kinematic parameters of missiles comparing RL.
http://www.mediafire.com/?cbftd9sqk8038
Fixing the guidance is very easy, simply you have to set exaclty the same value as for SA-2 or something similar. One thing is sure. Current is useless.
It is sad to say but how were tested the BMS4? From the basic radar guided SAMs (SA-2/3/4/5/6) I have tested only three but two are useless in this release. They are 99,9% ineffective…
Altitude profile from a test.
Velocity profile.
Some thrust profile, I will explain what is important for Falcon.
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Basicly we have to choose between two profiles.
Against low-medium al targets this thrust-time characteristic is used.
Against high flying and distant targets this.
The booster stage is WIP, it should be bigger, the speed after the solid fuel rocket booster stage is about 800 m/s (1550 kts)
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As usual the weight data is very inaccurate.
Original data
6172.94 # Weight of Missile (lbs)
3800 # Weight of propellant (lbs)RL data
Translation of important data.
Total weight of 2nd stage: 3900 kg (~8’600 lb)
Weight of fuel (TG-02): 586 kg (~1’300 lb)
Weight of oxidyzer (AK-27P): 1680 kg (~3’700 lb)
Total weight of propellant: 2266 kg (~5’000 lb)
–---------------------------------------------
Burnout weight = (Total weight of 2nd stage)-(Total weight of propellant) = 3’600 lbTranslating to Falcon
3600 # Weight of Missile (lbs)
5000 # Weight of propellant (lbs) -
Thank you so much molni for the work you do!
BMS Falcon is a great F-16 simulator - the greatest on PC.
AND: Falcon is a simulator with dynamic campaign engine - no other flight sim has that.The database is the flesh on the sceleton and even part of the nerval system in this camp engine i think.
It is sad that even the most common things (AA/AG missiles/enemy planes/…) a falconeer encounters on a campaign flight are not realisticly modelled at all.
… i’m coming thirsty out of the OF desert (i remember a “Yoda missile thread” or so) - don’t know about the FF database (i read somewhere here that they did something about it)-anyhow:
wonderful to see that someone takes care of this >lack< in realism (finally).:D
for now we fly the most realistic F-16 - you seem to add the most realistic campaign machine. :bdance:
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It is sad that even the most common things (AA/AG missiles/enemy planes/…) a falconeer encounters on a campaign flight are not realisticly modelled at all.
The problem is more serious. You can argue about realism factor but SA-3/5 simply do not work because of their modeling values.
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Test result with original values. The ACMI have been uploaded, you can identify by its filename.
The vertical dashed line shows the moment where missile passed beyond the target (me), after ~85 sec of flying.
Flight path is not so bad, but speed characteristics is totally wrong. In RL. Likely the program 105 was used.
100kN thrust 0-40 sec, then dropping the thrust to 32 kN 40-60 sec.It is still a big question what for me what thrust model should be applied in later stage. It is very time consuming to show all result and I have reference about only very high alt test. Even if I set better drag data, at low altitude with program 105 missile can break Mach 4 at low, which in RL was a structural limit. Maybe, I have to choose the intermedet solution the 153-201 thrust char.
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No i know why those Sa-3 and SA-5 don’t hit me even i just evade them with all my boms under wings and cat 3
This is very,very bad broblem. Is there any way to fix it even bit for next relase?
Good work Molni :headb:
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Test results in Excel with two different thrust char.
http://www.mediafire.com/?jh02tb8vohjni74
ACMI files are availabe the posted link.
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http://www.mediafire.com/?n6ff9wtnbn44ri9
Engagement zone of S-200.
I prefer to use program 201, even it is unreal for high altitude targets, but because of the limited engagement distance and bubble it is more suitable against low and high flying tagerst eihter in Falcon’s environment. You can see that against low flying closing target the engagement distance is much smaller.
FM is not fine tuned but better than original.
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I have many russian performance graphs myself (mostly jets) …but why is it that they always appear as being written on toilettepaper after a good vodka night…or is that just me ?
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Stealth flag controls the day/night operations as I know.
That is all……it doe’s
You set it on and then they will only be tasked to fly at night……;)
demer
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AoA tweaks on F-15, effect both on player and AI controlled AC.
Tuning the F-15, what is the point to reduce the angle of attack, unless the original model of the flight is not correct? CL, CD, does not correspond to reality. And if you reduce the angle of attack is what happens to the insant turn?
Are you sure that the mass of the missile is calculated in this way?
Formula or line of falcon code?
How about the other changes to the A-A missile:
Gimbal Angle Limit (deg)
Gimbal Angle Rate Limit (deg/sec)
Field of View (deg)
Missile loft time
What range we transfere to terminal guidance
maxGTerminal
maxGNormal
?
And when you change engine burntout time and engine thrust, where the check for the total momentum?