FC3 MiG-29A vs FF Mig-29 9.12A - inconsistant Launch Authorized Distances

[okopanja]

Provided are 3 test cases demonstrating the inconsistencies in PR (LA) given when launching R-27T(ET) and tracking target with radar.

Distances were measured in game by pausing the game:

- (Indicated) Maximal range:  the mid-point of arrow was overlapped with distance marker

- Launch Authorized distance: first occurrence of PR signal on HUD

- Missile launch distance: Missile indicator removal from HUD

Given the fact that both platforms (FC3 and FF) use the same missiles one would expect that there would be minimal difference.

In case of (Indicated) maximal range difference is not too high. 

However remaining 2 measurements differ greatly and affect employment of the weapon in full head on scenarios. In addition FF MiG-29 9.12A is more exposed to enemy action.  

In order to account for 2 second of delay between pressing the launch button and activation of missile, in all cases the button was pressed and held before entering the max range zone. If these 2 seconds would be taken into account and pressed exactly when PR(LA) shows up, the distance discrepancy would increase further. 

The following measurements were taken including the differences (FF-FC3):

Mig-29 at 1100m launching R-27T on F-15C in AB at 2000m head on:
  FC3 MiG-29A:
    Max range: 12.0km
    Launched Authorized: 11.98km
    Missile Launched: 11.75km
  FF MiG-29 9.12A:
    Max range: 11.6km
    Launched Authorized: 9.91km
    Missile Launched: 9.58km
  Difference:
    Max range: -0.4km
    Launch Authorized: -2.07km
    Missile Launched: -2.17km
Mig-29 at 8000m launching R-27ET on F-15C in AB at 8000m head on:
  FC3 MiG-29A PR at:
    Max range: 35.23km
    Launched Authorized: 35.21km
    Missile Launched: 34.95km
  FF MiG-29 9.12A PR at:
    Max range: 34.74km
    Launched Authorized: 23.57km
    Missile Launched: 23.11km
  Difference:
    Max range: -0.49km
    Launch Authorized: -11.64km
    Missile Launched: -11.84km
Mig-29 at 12000m launching R-27ET on F-15C in AB at 12000m head on:
  FC3 Mig-29A PR at:
    Max range: 54.68km
    Launched Authorized: 36.63km
    Missile Launched: 36.19km
  FF MiG-29 9.12A PR at:
    Max range: 53.45km
    Launched Authorized: 23.23km
    Missile Launched: 22.78km
  Difference:
    Max range: -1.23km
    Launch Authorized: -13.4km
    Missile Launched: -13.41km

Supporting files:
  - tacviews
  - mission file
  - side by side video comparison

 

MiG-29A_R-27T_head_on_12000m_Launch_Authorized.trk MiG-29A_R-27T_head_on_12000m_Launch_Authorized.zip.acmi MiG-29_9.12A_R-27T_head_on_12000m_Launch_Authorized.trk MiG-29_9.12A_R-27T_head_on_12000m_Launch_Authorized.acmi MiG-29A_R-27T_head_on_8000m_Launch_Authorized.trk MiG-29A_R-27T_head_on_8000m_Launch_Authorized.zip.acmi MiG-29_9.12A_R-27T_head_on_8000m_Launch_Authorized.trk MiG-29_9.12A_R-27T_head_on_8000m_Launch_Authorized.zip.acmi MiG-29A_R-27T_head_on_1100m_2000m_Launch_Authorized.trk MiG-29A_R-27T_head_on_1100m_2000m_Launch_Authorized.zip.acmi MiG-29_9.12A_R-27T_head_on_1100m_2000m_Launch_Authorized.trk MiG-29_9.12A_R-27T_head_on_1100m_2000m_Launch_Authorized.zip.acmi R-27T Launch Authorization.miz

[AeriaGloria]

Your first video at low altitude I believe is just the 1-2 seconds to get missile ready being simulated. 
 

I don’t know what’s going on at high altitudes if your target is AB the whole time 

[okopanja]

2 minutes ago, AeriaGloria said:

Your first video at low altitude I believe is just the 1-2 seconds to get missile ready being simulated. 

I picked low altitude and AB target at 2000m, to give it a bit of more exposure. I can redo co-altitude 2000m, but I am pretty sure I will get larger difference.

3 minutes ago, AeriaGloria said:

Your first video at low altitude I believe is just the 1-2 seconds to get missile ready being simulated. 
 

I don’t know what’s going on at high altitudes if your target is AB the whole time 

All targets were set to high speed. However I set 12000m F-15C to 2500 km/h, maybe I should have set it to 2800 km/h, just to ensure its on the full burner all the time.

Still goal was to compare them under same conditions.

[0minutes]

Yeah, its like they are two different missiles, i wonder if its because the 29FF perhaps prepares the R27T(E) differently? Also, maybe if the seeker is cooled differently on the 29FF since in the Su-27 there is an option to enable cooling on the R73, but im just brainstorming with no actual proof. Overall i hope this gets fixed though, pretty annoying having the most reliable R27 be artifically nerfed on the 29FF.

[okopanja]

2 minutes ago, 0minutes said:

Yeah, its like they are two different missiles, i wonder if its because the 29FF perhaps prepares the R27T(E) differently? Also, maybe if the seeker is cooled differently on the 29FF since in the Su-27 there is an option to enable cooling on the R73, but im just brainstorming with no actual proof. Overall i hope this gets fixed though, pretty annoying having the most reliable R27 be artifically nerfed on the 29FF.

As far as I can tell they are the same missile. There is no second R-27ET. It's just probably the problem on how PR on 29FF works at the moment.

[0minutes]

2 minutes ago, okopanja said:

As far as I can tell they are the same missile. There is no second R-27ET. It's just probably the problem on how PR on 29FF works at the moment.

Yes I know, i meant is as sarcasm/irony, to show how absurd it is that they act so differently while being the same missile.

[AeriaGloria]

I don’t k ow why this was moved to FC3 section. 

According to other modules and know. Calculations of DCS IR seeker ranges, the FC3 module is actually using the R-27T/ET at the correct distances and it’s the MiG-29 FF 9.12A that’s the outlier with shorter distances 

[Ironhand]

What I find interesting is how, at 12000 m altitude, the distance travelled between launch authorization and the actual launch is nearly identical (0.01 km difference). OTHOH, the difference at 1100 m is 0.1 km and 0.2 km at 8000 m. Why is that? Differences in closure rate?

Edited Monday at 01:16 PM by Ironhand

[okopanja]

6 hours ago, Ironhand said:

What I find interesting is how, at 12000 m altitude, the distance travelled between launch authorization and the actual launch is nearly identical (0.01 km difference). OTHOH, the difference at 1100 m is 0.1 km and 0.2 km at 8000 m. Why is that? Differences in closure rate?

On each altitude closure rate is the same between FC3/FF. Basically both are 0 km/h, so the only thing there to contribute do closure rate is speed of the target.

I wish I recorded timings, but this would require some coding. 

[Ironhand]

That’s interesting. I was only going by the data you presented and hadn’t watched the videos. You used active pause. So there’s a variable not account for. Either the target aircraft were flying at different speeds within the first two test groups or the “own” aircraft speeds are not identical as assumed. I suppose both could be true, though. The 11,800 m test is the one where they were identical.

EDIT: Maybe I’m making a mountain out of a mole hill. And this isn’t a criticism of your test procedure. It just seems that something is amiss and it might not be the missile.

Edited 12 hours ago by Ironhand

[okopanja]

17 minutes ago, Ironhand said:

That’s interesting. I was only going by the data you presented and hadn’t watched the videos. You used active pause. So there’s a variable not account for. Either the target aircraft were flying at different speeds within the first two test groups or the “own” aircraft speeds are not identical as assumed. I suppose both could be true, though. The 11,800 m test is the one where they were identical.

Launch platforms are at exact locations, heading (including next waypoint), altitudes and speed.
Targets: low targets are set to I think 1500 km/h. 12000 target is set to 2500 km/h. Need to confirm 8000m target. 

One thing I regret was not measuring the time (presently in DCS this would mean 1s resolution). In general for more precise distance/timing measurements I would need to write specialized software.

 

[Ironhand]

Unfortunately I won’t have access to my computer for another week or so. I’d love to take a closer look at some of the assumptions that we’re making. OTOH, it certainly seems that the missile interacts differently with the two platforms.