[EVALUATING] ASP for A-2-A gun use incorrect / Radar

[FSKRipper]

 

Sorry your datacard contains many untrue informations. MiG-21M/MF NEVER had ASP-5 gunsight ( only F/F-13, U, some US ), no difference in search range between RP-21M i RP-21MA and both are search radars not rangefinders, IFF system is SRZO-2 not SRO-2 (find the difference ). Every ( polish or czech or soviet ) military manuals stating that ASP-PFD-21 use information from radar. Those papers are OFFICIAL military documents, I don't understand why some people deny their value as a source of information.

 

Thank you for this advise. I contacted the webmaster of the regarding site (http://www.mig-21-online.de/) and he confirmed the mistake (he also uses official military documents btw).

Regarding the SRZO his statement was, that he will check it with some fellow technicians but according to his written remarks for the maintenance book the NVA 21-M used a SRO "Chrom" and not the SRZO "Chrom-Nickel". The SRZO with a higher frequency count and more resistance to jamming came in later models to the "Jagdfliegergeschwader 8". He don't insists that this was true for all east german squadrons.

 

 

 

 

You could start with the page I linked in the original post. Basically it says:

 

 

 

Another page at the bottom: http://www.muzeumlotnictwa.pl/digitalizacja_archiwaliow/katalog/1363/94.jpg

 

 

 

Sorry for not grammatically correct translation, the original document is very technical and not grammatically correct either.

 

Thanks for your translation. That was the kind of information I was looking for in a half dozen of threads regarding the ASP. :thumbup:

[Harle]

Here we go.

However, I'm not sure what this "housing" (корпус) is about. Not sure if I chose the right term. But I suspect it might mean a configuration of ASP switches.

Edited March 16, 2015 by Harle

[foxbat155]

Thank you for this advise. I contacted the webmaster of the regarding site (http://www.mig-21-online.de/) and he confirmed the mistake (he also uses official military documents btw).

Regarding the SRZO his statement was, that he will check it with some fellow technicians but according to his written remarks for the maintenance book the NVA 21-M used a SRO "Chrom" and not the SRZO "Chrom-Nickel". The SRZO with a higher frequency count and more resistance to jamming came in later models to the "Jagdfliegergeschwader 8". He don't insists that this was true for all east german squadrons.

 

SRO-2 and SRZO-2 generally is the same device. Between them is only one difference: SRO-2 is a "answer" device and is able only response for IFF system inquiry. SRZO-2 is "question" and "answer" device, she is able response for others inquiry and formulate "question" signal. "Question" signal can by transmitted by fire control radar only. So all MiG-21 variants with radar: MiG-21PF/PFM/R/S/SM/SMT/M/MT/MF/bis are equiped with SRZO-2, variants with gun rangefinder: MiG-21F/F-13/U/US/UM have SRO-2. When technicians saying about earlier/later model they probably means SRO-2/SRZO-2 and SRO-2M/SRZO-2M.

[FSKRipper]

SRO-2 and SRZO-2 generally is the same device. Between them is only one difference: SRO-2 is a "answer" device and is able only response for IFF system inquiry. SRZO-2 is "question" and "answer" device, she is able response for others inquiry and formulate "question" signal. "Question" signal can by transmitted by fire control radar only. So all MiG-21 variants with radar: MiG-21PF/PFM/R/S/SM/SMT/M/MT/MF/bis are equiped with SRZO-2, variants with gun rangefinder: MiG-21F/F-13/U/US/UM have SRO-2. When technicians saying about earlier/later model they probably means SRO-2/SRZO-2 and SRO-2M/SRZO-2M.

 

Would you be able to share additional information/manuals with us? The contact mentioned above said that technical details and construction plans were not defined in their maintenance books. These details were treated as secret. All "modern" IFF equipment with malfunctions had to be removed and directly shipped back to the Soviet Union without opnening it and try a repair.

[foxbat155]

Here is SRO-2/SRZO-2 manual (djvu file), enjoy:

 

http://www.filedropper.com/327e0ea8124dd754fa942193039caaca1

Edited March 16, 2015 by foxbat155

[FSKRipper]

Very nice, thanks. It will take some weeks but after that my russian skills will be as good as 15 years ago :megalol:

[finger]

Here we go.

However, I'm not sure what this "housing" (корпус) is about. Not sure if I chose the right term. But I suspect it might mean a configuration of ASP switches.

-KORPUS- this is -(minus) el.polarity /ground/

[Harle]

Oh, my bad. Fixed. The only term for groung/grounding I heard being used in everyday life is "земля/заземление". Looks like there's a bit different terminology in aircraft engineering.

Edited April 1, 2015 by Harle

[JaNk0]

This is some serious investigation

[finger]

Oh, my bad. Fixed. The only term for groung/grounding I heard being used in everyday life is "земля/заземление". Looks like there's a bit different terminology in aircraft engineering.

 

Yes,yes this is russian way.

[FSKRipper]

Ok I found another document for the three gunsgight versions (ASP-PFD, ASP-PFM, ASP-PFM-B) of east german M/MF series implying auto range in a status called "locked".

cover.pdf

gunsight.pdf

Edited March 18, 2015 by FSKRipper

[Harle]

Now after all that's been said here, I'm rather curious about the progress that LN are making with the ASP.

Cobra, will you be so sweet as to indulge us with some kind of work status update?

Some pips in the russian section of the forum are going pretty emotional on the topic.

Edited March 22, 2015 by Harle

[finger]

Now after all that's been said here, I'm rather curious about the progress that LN are making with the ASP.

Cobra, will you be so sweet as to indulge us with some kind of work status update?

Some pips in the russian section of the forum are going pretty emotional on the topic.

 

So,what next?

[Harle]

So,what next?

 

Nothing. Why do you ask?

[FSKRipper]

Patience young padawan. Emotions are the way to the dark side :music_whistling:

 

Maybe you should relay this to the guys in the russian section. A serious investigation takes some time and as you can see in the thread title, evaluation is in progress.

 

Please remember that these complains, bashing posts and emotinal but not rational comments made Wags canceling the weekly development update.

[finger]

No problem,I have holiday in next two week.Any aircraft,any computer ,any

internet,any phone.Only relax.

[FSKRipper]

No problem,I have holiday in next two week.Any aircraft,any computer ,any

internet,any phone.Only relax.

 

It was adressed to Harles #162 :lol:

But happy holidays from my side!

[sissypilot]

Whaooo.

I have checked on the game and something changed. It is still light years from the real one but certainly better: ballistics is definitely better, still when lock no distance indication I assume no impact calculation either, bombing CCIP still works as if in a tie fighter :) piper still locks on plane when IR missile lock (it is very annoying, with minimal reasoning it is easy to understand that there is no way ASP would know and indicate where our target is located in front of us, especially our ASP which is unable even with radar lock to calculate distance in AA gun mode let alone position).

[cz_jc]

Whaooo.

I have checked on the game and something changed. It is still light years from the real one but certainly better: ballistics is definitely better, still when lock no distance indication I assume no impact calculation either, bombing CCIP still works as if in a tie fighter :) piper still locks on plane when IR missile lock (it is very annoying, with minimal reasoning it is easy to understand that there is no way ASP would know and indicate where our target is located in front of us, especially our ASP which is unable even with radar lock to calculate distance in AA gun mode let alone position).

can't it just be displaying data from the IR seeker head ? F-16 could do that.

[sissypilot]

If it would be so IR seeker knows only relative to aircraft axis direction but no distance. To point out something on the HUD you need both. There is no such data exchange in MIG-21 you only hear the tone when IR head locks and have a lock light on.

And think about it: our ASP does not know distance in AA gun mode radar locked when badly needed and happen to know distance during IR lock when showing target is really only a "cool" feature not really more, even with swiched off radar.. comeon leatherneck you are better than that :)

 

Somehow I would like to believe that we do not belong to that market segment which welcomes "cool features" in a high fidelity simulation, but contrary demand the real ones :)

Edited April 2, 2015 by sissypilot

[Dudikoff]

If it would be so IR seeker knows only relative to aircraft axis direction but no distance. To point out something on the HUD you need both.

 

Pardon my ignorance, but why would you need anything besides direction to "point out something on the HUD"? I didn't really check the context of the MiG-21 HUD, but in general such a thing is not needed depending on the usecase (e.g. uncaged Sidewinder seeker on e.g. F-15 would show what it's locked onto and it most certainly doesn't know the range).

[sissypilot]

I dunno about the workings of an f-15 (thouh I happen to know that a real mig-21 would not show IR lock on ASP), but simple geometric rules make it impossible to point out something in 2d knowing only one dimension which is direction you need distance too. If you rely only on the seekers input you see only a line on the ASP to make it a point you need distance too.

My guess is that F-15 HUD communicates both ways to the seeker and to the radar or only the radar point out the target for the HUD based on the seekers input either way it must works with two variables. One thing is sure: a Mig does not do such thing in reality.

[GGTharos]

That is incorrect. The HuD on the f15, 16, a10 etc does NOT need range input to display seeker fov. The software knows where the seeker is located and can place the fov marker with minimal parallax error. Further, past a certain range the error won't even be noticeable.

 

The reason a MiG-21 does not display the seeker cue probably has more to do with system limitations (weapon information feeding to wcs) than not knowing range.

[sissypilot]

I have to agree as I have no knowledge on the workings of the f-15 or 16 HUD, I was just thinkink outloud, it is not the same if target is 500m or 5 km away, you might be right that between 0.8 and 3km which is probably the most comon engagement distance it means a minimal parallax. One thing sure as you sad the "software knows" on the US fighters and there is no software on the Mig to "know" :). The soviet designers simply did not think this feature is that important so it would be worth to take the effort to solve with an analogue system. However they did solve the rangefinding problem with the radar (even though there was not much to solve as this system was a couple of decades old by then) in A-A gun mode which is not implemented to remain ontopic.

[fjacobsen]

Range is really not needed only horizontal and vertical angular position, which is taken from the missiles seekerhead.

 

Imagine what the seekerhead is "seeing" - a big circular area, which is it´s total field of view. A hot target would be a spot somewhere on that area if the target is within the seekerheads field of view.

This position can then be overlayed on the HUD.

Just like the seekerhead cannot measure the distance, the relative position can still be determined and indicated on the HUD.

This is the way it works on fighters like the F-16, F-15, F/A-18 etc..

Inorder to lock an IR-missile and have the position shown on the HUD, You don´t need a radra lock, nor any other means of distance measurement.

You just need to get input where the missileseeker is looking at a target and is locked. and somewhere on that line of the sight You will find the target, regardless of distance.

 

FinnJ