R-27ER update?

[FoxAlfa]

That's great, but he's wrong just like he was wrong with his original estimates. Bring this to ED, and see what happens. If you're on the ball they'll listen.

 

 

Ingame DCS data on 20/01/2019 of R-27ER... aerodynamic range ~ 21km... target travel with 1100km/h in that time ~12km, so all in all 33km...

 

An image you provided for the real-life Flanker manual...

 

Agh 39km, those silly Russians are telling their pilots to fire the missiles 6 km too early.... we must let them correct the manual since you are correct.

[GGTharos]

Ok, so bring it up with ED. You know Russian, you can bring it up right in their forum.

[FoxAlfa]

Ok, so bring it up with ED. You know Russian, you can bring it up right in their forum.

 

I don't speak Russian, I speak Serbo-Croatian... completely different language... and all we ever asked is for ED to comment, unfortunately, you seem to be applying for the position of their lawyer... in the end, if somebody can explain where my logic of the Conclusion 2 is wrong:

 

"And in the end, if we take into account that R-27R bleeds much more speed in turn that R-73 the effective range difference for a maneuvering target between them becomes neglectable.

And these missiles were developed at the same time for the same planes.

 

I can't image a Soviet rocket Scientist going to a Military Officer and saying well it will have maybe 20% bigger range if you are above the 5000m and if the target doesn't turn and if the radar doesn't drop a lock and it will cost more and you can only have two on your Front line fighter since it is 2.5 times heavier with all the added cost of logistics and maintenance... and the Officer goes, yes please, give me those 20% please... It doesn't pass the common sense test..."

 

I would be happy.

[JunMcKill]

Meanwhile ED continues working on western missiles :D

 

DCS World

- Fixed crash if tank has been destroyed while shooting.

- AIM-7. Loft trajectory corrected. Arm delay increased for safe launch.

- MP. AIM-7. Net phantom (client side) of missile always flies straight ahead fixed

[GGTharos]

No, they're working on new FM. AIM-7s are broken right now for MP. They have problems that you'd probably really want them to fix, and I don't mean missile performance - things like false missile launch warnings etc.

 

I don't even see how you can imply a complaint like this, something like that last line in your quote means you get to explode without any warnings etc.

[JunMcKill]

No, they're working on new FM. AIM-7s are broken right now for MP. They have problems that you'd probably really want them to fix, and I don't mean missile performance - things like false missile launch warnings etc.

 

I don't even see how you can imply a complaint like this, something like that last line in your quote means you get to explode without any warnings etc.

 

I know is broken, as I know that if you want to shot down someone with a R-27ER, I have to launch it at 8km maximum, I play daily in the 104th server in MP, and the ER use is only for persuation, in order to make the other aircraft begin defensive maneuvers, not thinking in a kill, because the Pk is almost ZERO!

Edited January 24, 2019 by JunMcKill

[FoxAlfa]

I did another test, compared HUD data from a youtube of a Real Life with the DCS hud.

There are some errors in the height and speed of me, but the target is spot on.

The Missile is R-27r

 

 

I must admit I am a bit baffled.

 

Firstly I think the hud calculation in the game is good, it works good enough for all missiles.

 

So the flight profile for the R-27r seems incorrect in the game. In RL it has a bigger lethal range 8km vs 4 km range, but a smaller range against a non-maneuvering target 15km vs 23 km.

 

I there are a lot of ways that missile could have to achieve this, per example less speed loss during a maneuver giving her bigger lethal arc but bigger drag reducing the overall range or longer sustain of an engine but lower max speed or stronger missile parameters but a hard time cut of due to power loss or earlier stall.... lot of options... and like I said I am baffled....

 

GGTharos, any ideas, what do you think would reproduce these Real Life parameters?

Edited January 24, 2019 by FoxAlfa

[FoxAlfa]

Ok, the non-manuvering range is larger since I missed that the RL was turning away from the target...here is the new picture.... if you turn away we get the similar results... but the lethal range is still cut in half from RL...

 

[GGTharos]

When you launch an ER at me I definitely get persuaded to do something. :)

 

I know is broken, as I know that if you want to shot down someone with a R-27ER, I have to launch it at 8km maximum, I play daily in the 104th server in MP, and the ER use is only for persuation, in order to make the other aircraft begin defensive maneuvers, not thinking in a kill, because the Pk is almost ZERO!

[GGTharos]

I did another test, compared HUD data from a youtube of a Real Life with the DCS hud.

There are some errors in the height and speed of me, but the target is spot on.

The Missile is R-27r

 

Yep, I'm familiar with this video :)

 

I must admit I am a bit baffled.

 

Firstly I think the hud calculation in the game is good, it works good enough for all missiles.

 

I would disagree with you here, the HuD calculation is too simple. I'm disagreeing on the technical note though.

 

So the flight profile for the R-27r seems incorrect in the game. In RL it has a bigger lethal range 8km vs 4 km range, but a smaller range against a non-maneuvering target 15km vs 23 km.

 

I agree with you but with the caveat that I don't know what is supposed to be represented by the middle line. I can assume Rtr, but then what exactly are those Rtr parameters?

 

I there are a lot of ways that missile could have to achieve this, per example less speed loss during a maneuver giving her bigger lethal arc but bigger drag reducing the overall range or longer sustain of an engine but lower max speed or stronger missile parameters but a hard time cut of due to power loss or earlier stall.... lot of options... and like I said I am baffled....

 

GGTharos, any ideas, what do you think would reproduce these Real Life parameters?

 

I have some ideas, and I would have to defer with Chizh because he (Well, ED) know a lot more about these missiles than I do - my surprise here is that they are saying that the R-27 family does not use the variable PN constants. And I supposed that's ok-ish, but it should be at least as capable as sparrow with respect to a longer-range vs 'dogfight' type mode (automatically set in the missile based on distance to target at launch).

 

So, I personally believe the variable PN could be used to simulate such a set-up.

 

This stuff is just off-the-top of my head. What I can say is that if you were to naively look at the AIM-7E diagrams, you'll see that missiles lose capability very quickly vs specific constant target g. The R-27R would have a little more range than the 7E, but the 7E's range was not very impressive to begin with.

 

Finally, despite the 'simplicity' of certain weapons like the R-27R, they are still very complex devices with a lot of filters etc. I think they should be a little more capable of preserving their energy. A big component of this is that these missiles fail to fly-out to a predicted intercept, and instead they use PN steering exclusively. This wastes energy.

 

PS: IIRC, the Rmax represetned on the real HuD is supposed to represent a 0.7Pk against a non-maneuvering target. I don't know what means means in terms of what the missile is doing though.

Edited January 24, 2019 by GGTharos

[FoxAlfa]

Yep, I'm familiar with this video :)

 

I have some ideas, and I would have to defer with Chizh because he (Well, ED) know a lot more about these missiles than I do - my surprise here is that they are saying that the R-27 family does not use the variable PN constants. And I supposed that's ok-ish, but it should be at least as capable as sparrow with respect to a longer-range vs 'dogfight' type mode (automatically set in the missile based on distance to target at launch).

 

So, I personally believe the variable PN could be used to simulate such a set-up.

 

This stuff is just off-the-top of my head. What I can say is that if you were to naively look at the AIM-7E diagrams, you'll see that missiles lose capability very quickly vs specific constant target g. The R-27R would have a little more range than the 7E, but the 7E's range was not very impressive to begin with.

 

Finally, despite the 'simplicity' of certain weapons like the R-27R, they are still very complex devices with a lot of filters etc. I think they should be a little more capable of preserving their energy. A big component of this is that these missiles fail to fly-out to a predicted intercept, and instead they use PN steering exclusively. This wastes energy.

 

PS: IIRC, the Rmax represetned on the real HuD is supposed to represent a 0.7Pk against a non-maneuvering target. I don't know what means means in terms of what the missile is doing though.

 

I completely agree with you on the variable PN, it would increase the 'lethal' range without impacting the 'non-maneuvering' range which seam consistent with the video.

 

Another argument for 'variable PN' is that it was used on AIM-7E, which Soviets got and copied

in 1968 as K-25, which in the tests got outperformed by the R-23... but the lessons from its development were used in the R-27 development.

 

And with the increased lethal range/less energy bleed of the R-27, there would be enough performance difference between the R-27 and R-73 to warrant two missiles.

[GGTharos]

I don't know what the 'lethal range' mark actually represents. I haven't asked ED. I don't remember any more if you can affect the calculation of this mark in any useful way, but I would suggest running tests on the R-27R to see what this lethal range actually is, according to whatever criteria you want.

[FoxAlfa]

I don't know what the 'lethal range' mark actually represents. I haven't asked ED. I don't remember any more if you can affect the calculation of this mark in any useful way, but I would suggest running tests on the R-27R to see what this lethal range actually is, according to whatever criteria you want.

 

When based on the Yugoslav manual they are referenced three times or so,

 

first on the HUD diagram marked as Dd max1 and Dd max2

 

and later in the table 10a:

 

It says that pilot should fire on the first mark if the target is not maneuvering and on the second if the target is maneuvering if above 4000m and (first mark - 2 km) and (the second - 2km) below 4000m.

 

the third time in the text it says the pilot should fire the first r-27r on the first mark and the second on the second taking in account target maneuvering and then perform the exit maneuver.

 

And based on a lot of tests plus 150 hours+ on Blue Flag and the roughly same amount of kills in past few months in a MiG-29, I don't think I ever scored a kill on maneuvering target if I fired before the Dd max2 (aka ' lethal' range), that is why I am taking it to be good calculated.

[GGTharos]

Ok, so this doesn't really explain anything with respect to target maneuvers or missile behavior.

[FoxAlfa]

Ok, so this doesn't really explain anything with respect to target maneuvers or missile behavior.

 

Unfortunately no, it is more like mental algorithm using boolean, maneuvering true or false... subtract -2 if below 4000m...

[GGTharos]

PPS/ZPS is head-on/tail-on?

[FoxAlfa]

PPS/ZPS is head-on/tail-on?

 

Yes it is :)

[falcon_120]

I take the opportunity to leave this article from an american pilot perspective, he flew mig29s. It talks there how dissapointing the R27R was but I put it here just because is interesting, not because it gives any sciencetific input. His opinion could be based on a lot of factors like being a very first generation of R27R, etc.

 

Anyway its worth a reading:

https://foxtrotalpha.jalopnik.com/how-to-win-in-a-dogfight-stories-from-a-pilot-who-flew-1682723379

 

Enviado desde mi SM-G950F mediante Tapatalk

[Dudikoff]

I take the opportunity to leave this article from an american pilot perspective, he flew mig29s. It talks there how dissapointing the R27R was but I put it here just because is interesting, not because it gives any sciencetific input. His opinion could be based on a lot of factors like being a very first generation of R27R, etc.

 

There was also a German page related to JG-73 pilots and they posted some effective range data for the missiles from their experience, but for the life of me, I can't find it anymore. Perhaps it was taken down.

 

I do remember one of the things they've said was how they were negatively surprised by the R-27R range.

Edited January 25, 2019 by Dudikoff

[AeriaGloria]

I always wondered if his comment about the EOS, maybe he was not instructed in its proper use? Being an American pilot did he want to believe or spread word that it was not a threat? Everything else he mentions is true, but I’m not the only one who has wondered about his EOS comment, there’s their pilots that said it made trainees very frustrated when they would get decimated by si hosted OBS launches from aggressors.

 

Sorry to be OT, it’s almost good to hear his negative experience with the R-27 as it backs up the current ED model

Edited January 25, 2019 by AeriaGloria

[Vatikus]

Here is sample from 29 manual on how the DLZ is calculated. It shows briefly how it works with enough detail to see what all is being calculated at Rmax1, Rmax2 and Rmin.

[JunMcKill]

When you launch an ER at me I definitely get persuaded to do something. :)

 

If you do the same with the M2000's Matra 530 you are dead!, AFAIK, the 530 is the best SARH missile in ED right now.

[GGTharos]

I can evade 530s but yes, they are over-tuned for chaff rejection compared to other DCS SARH missiles.

 

I do wish the CM-handling would get a revamp, it's very dicey right now IMHO.

[Vilab]

Not only the chaff effectivness is very random, but it is also highly unrealistic in DCS

 

 

The chaff should affect the tracking radar ( which it doen't in DCS ), while it should barely annoy the SARH missile itself :

 

 

- assuming the radar keep tracking correctly it should make the quite early SARH missile think the target is slightly bigger and more backward than the actual target, and only as long as the chaff is inside the narrow emitting radar beam.

- the more modern SARH with doppler filter would only be affected by clutter/noise/mask effect

 

 

Moreover, the chaff should have some chances to trigger radar/laser fuses, while the flares and AB plumes should have some chances to trigger ( early/crappy ? ) IR fuses ( see Magic-I )

[GGTharos]

I don't know why you believe the chaff would affect the (more powerful in every way) tracking radar more than the missile ... yes, CM simulation should be advanced from what it is right now, IMHO but if you believe that doppler discrimination alone is a magical anti-chaff bullet, there are bridges to be sold :)