Bewildering R-77 behaviour

[okopanja]

13 hours ago, Ironhand said:

The best way to test would probably be to set up a server with two slots and run the scenarios. That way you can run tests with more precise profiles. Might be easier to figure out what causes what. TRK files would also be manageable.

Here is one example that does not full go to extreme I observed before.

ET was fired first and ER after. ET did hit the target, I zoomed in so we can have common timelines.

You can see AoA spike that is kind of unexpected. In the past I would see more of those.

I gather I will have to look for better example along trk file. 

I also think that latency might play the role here, so local server would not be perfect due to low latency.

 

Edited August 16, 2022 by okopanja
removed null

[Ironhand]

4 hours ago, okopanja said:

Here is one example that does not full go to extreme I observed before.

ET was fired first and ER after. ET did hit the target, I zoomed in so we can have common timelines.

You can see AoA spike that is kind of unexpected. In the past I would see more of those.

I gather I will have to look for better example along trk file. 

I also think that latency might play the role here, so local server would not be perfect due to low latency.

 

 

I guess I don’t see what you’re referring to. The profiles look similar to me. They wouldn’t be identical because the target is maneuvering and the missiles are not in the same piece of sky. But, if there is a difference, could it be biting on chaff and, then, relocking on the real target?

Edited August 16, 2022 by Ironhand

[okopanja]

1 hour ago, Ironhand said:

I guess I don’t see what you’re referring to. The profiles look similar to me.

Yellow mark. Back than, I had multiple such events for ER. Right now I have only keyboard, with me so until I return I can not properly fly.

1 hour ago, Ironhand said:

But, if there is a difference, could it be biting on chaff and, then, relocking on the real target?

No chaff or flares were involved. Lock was stable all the way, but I had lots of AoA spikes originally. I am aware that ER goes after chaff, even if not notching...

As said I will have to take a closer look, perhaps it was server related...

[AeriaGloria]

On 8/14/2022 at 6:46 AM, FlankerFan35 said:

Do correct me if I'm wrong but all the public info I could find gives the 77 an RMAX of 80km but in DCS it struggles greatly and is seen as a miracle if it reaches 40km and often just flips out of control and drops like a rock losing hundreds of knots in 1.5 seconds, when I tested it at 12,500m at Mach 2.2 I reached only 77km max.

Are advertised performance figures reached in this way in real life meaning the RMAX means at high alt and launch speed? if you have any information, please share it as I'd like to learn.

Again, I am aware this was the worst ever 77 variant.

The R-77 range figures are reportedly for a test at 20,000 meters altitude and Mach 2. So basically only MiG-31 is going to shoot it that far 

 

On 8/14/2022 at 2:48 PM, okopanja said:

I am pretty sure he meant IRL as well, hence I started my line with: "In DCS".

So there is some discrepancy in what is IRL and what is in DCS. E.g. for M-link we would need INS, and I am pretty sure its not in the DCS. Present implementation shows missile able to orient itself initially on launch, but this can be done even without sophisticated INS.

It’s been confirmed there is no INS in the missile, I believe the Host radar only tells it course changes, but the missile actually has no idea where it is, and only uses gyroscopes for control

[okopanja]

1 hour ago, AeriaGloria said:

It’s been confirmed there is no INS in the missile, I believe the Host radar only tells it course changes, but the missile actually has no idea where it is, and only uses gyroscopes for control

IRL/DCS?

Link?

[Cmptohocah]

5 hours ago, Бойовий Сокіл said:

IRL and DCS. He is refering to Datalink - how the missiles receives guidence commands before its seeker can see the target reflection. 

I think the question was: where the link to support the claim that is has/does not have INS?

[FlankerFan35]

On 8/16/2022 at 9:05 PM, AeriaGloria said:

The R-77 range figures are reportedly for a test at 20,000 meters altitude and Mach 2. So basically only MiG-31 is going to shoot it that far 

 

It’s been confirmed there is no INS in the missile, I believe the Host radar only tells it course changes, but the missile actually has no idea where it is, and only uses gyroscopes for control

Would be cool to see this info if you have it but I read also at low/medium altitude the weapon should still be able to travel 25-45km and it's not able to do this and what about the random loss of track and sudden loss of 500kts of speed and spinning?

[AeriaGloria]

10 minutes ago, FlankerFan35 said:

Would be cool to see this info if you have it but I read also at low/medium altitude the weapon should still be able to travel 25-45km and it's not able to do this and what about the random loss of track and sudden loss of 500kts of speed and spinning?

I don’t know about low altitude range, and I would need to see a track/tacview to explain any loss of track and spinning. 

But I was wrong it’s 100 km range is for a 1.5 Mach shot at 20,000 meters. The info is from interview with SD-10 designer 

[FlankerFan35]

Just now, AeriaGloria said:

I don’t know about low altitude range, and I would need to see a track/tacview to explain any loss of track and spinning. 

But I was wrong it’s 100 km range is for a 1.5 Mach shot at 20,000 meters. The info is from interview with SD-10 designer 

Cool thanks!

[GGTharos]

13 minutes ago, FlankerFan35 said:

Would be cool to see this info if you have it but I read also at low/medium altitude the weapon should still be able to travel 25-45km and it's not able to do this and what about the random loss of track and sudden loss of 500kts of speed and spinning?

Travel 45km at lo altitude, no.  And also, what did you actually read?  Travel or range?   I bet it was range, and in that case 25km at low altitude could maybe make sense, and 45km at medium altitude.  Altitude does not affect range linearly, but you could ballpark high altitude range to be 4x low altitude range.   Still, 25km is a long range at low altitude and likely assume something relatively easy ie. non-maneuvering and traveling high subsonic, like M0.8.  

[okopanja]

6 hours ago, AeriaGloria said:

I don’t know about low altitude range, and I would need to see a track/tacview to explain any loss of track and spinning. 

But I was wrong it’s 100 km range is for a 1.5 Mach shot at 20,000 meters. The info is from interview with SD-10 designer 

Alleged interview with unnamed person, posted and re-posted into different forums that are not active should probably not be considered. Please do not take offense, I really do not like to write something like this, I do not question your integrity.

Also consider the following, lets assume this interview really took place. From what I read inside this likely occurred somewhere at some weapons exhibition. Normally the people who attend this are people from sales on behalf of manufacturers, lots of people just curious of the things, journalists and very few actual customers. The job of the sales person is to sell, and as long as they can say something that can not be verified on spot. As a technical person I have been in this role (although not in defense, but rather security solutions). The weapons market is roughly divided into: west only buying, mixed buying customers, and eastern buying customers. Clearly 77 is the competitor in market terms with SD-10. Whoever buys AIM120 will likely not even consider buying any of the 2 (perhaps Turkey?). So the resulting financial pond for 77/SD-10 is more narrow, and there are 2 crocodiles out there. These exhibitions are also places where lots of funky things occurs ranging from planting rumors, sabotaging to downright steeling the samples of customers.

Personally I think it is likely that SD-10 is more advanced with longer range than original 77, since China had access both to 77 and aspide.

One thing I wanted to ask you how did you conclude it does not have INS from this article?

The way I read it from point 3 the designer claims:

- SD-10 has better INS (to be better, I gather there needs to be something in 77 to compare with)

- SD-10 has better signal processing

Was there another source?

[AeriaGloria]

4 hours ago, okopanja said:

Alleged interview with unnamed person, posted and re-posted into different forums that are not active should probably not be considered. Please do not take offense, I really do not like to write something like this, I do not question your integrity.

Also consider the following, lets assume this interview really took place. From what I read inside this likely occurred somewhere at some weapons exhibition. Normally the people who attend this are people from sales on behalf of manufacturers, lots of people just curious of the things, journalists and very few actual customers. The job of the sales person is to sell, and as long as they can say something that can not be verified on spot. As a technical person I have been in this role (although not in defense, but rather security solutions). The weapons market is roughly divided into: west only buying, mixed buying customers, and eastern buying customers. Clearly 77 is the competitor in market terms with SD-10. Whoever buys AIM120 will likely not even consider buying any of the 2 (perhaps Turkey?). So the resulting financial pond for 77/SD-10 is more narrow, and there are 2 crocodiles out there. These exhibitions are also places where lots of funky things occurs ranging from planting rumors, sabotaging to downright steeling the samples of customers.

Personally I think it is likely that SD-10 is more advanced with longer range than original 77, since China had access both to 77 and aspide.

One thing I wanted to ask you how did you conclude it does not have INS from this article?

The way I read it from point 3 the designer claims:

- SD-10 has better INS (to be better, I gather there needs to be something in 77 to compare with)

- SD-10 has better signal processing

Was there another source?

Sorry the quote image I used does not use the name and source. It is from Bing Gong Ke Ji Magazine, I believe a Chinese Military Journal. The name of the chief designer speaking in the interview is Lian Xiaogeng, he worked in Luoyang Electro Optical and CATIC, also designed PL-10, and died some years ago. You can see some of his published work here, he was affiliated with Shanghai Academy of Sciences and Technology https://www.researchgate.net/scientific-contributions/Liang-Xiaogeng-75191074

Also, I never meant that R-77 has no INS, it certianly does. But that R-27 has no INS, and only gyros and given course corrections by radar. This has been confirmed by Chizh (very top of ED, in charge of a lot of missile related development in ED and often discusses real life sources) on the Russian forums and English missile thread. I don’t have many other sources for that specific thing, other then no source saying R-27 has an INS, and the R-27 production pre dating any other missile sized INS in Soviet Union/Russia. 

Edited August 22, 2022 by AeriaGloria

[okopanja]

4 hours ago, AeriaGloria said:

Sorry the quote image I used does not use the name and source. It is from Bing Gong Ke Ji Magazine, I believe a Chinese Military Journal. The name of the chief designer speaking in the interview is Lian Xiaogeng, he worked in Luoyang Electro Optical and CATIC, also designed PL-10, and died some years ago. You can see some of his published work here, he was affiliated with Shanghai Academy of Sciences and Technology https://www.researchgate.net/scientific-contributions/Liang-Xiaogeng-75191074

Thanks, will dig there...

Meanwhile according to following sample of Chizh's Haiku Poetry, R-27 actually has INS. Rest of that topic is philisophy weather or not it should give warning, but it appears nobody knows for sure. Still this is 77 topic and I would not go deeper into it.

4 hours ago, AeriaGloria said:

But that R-27 has no INS, and only gyros and given course corrections by radar. This has been confirmed by Chizh (very top of ED, in charge of a lot of missile related development in ED and often discusses real life sources) on the Russian forums and English missile thread. I don’t have many other sources for that specific thing, other then no source saying R-27 has an INS, and the R-27 production pre dating any other missile sized INS in Soviet Union/Russia. 

Edited August 22, 2022 by okopanja
spelling is my weak point...