Missile Dynamics - A discussion

[GGTharos]

The problem here is that while this isn't entirely un-plausible, why not convert to using R-77's altogether?

 

Another problem: Who the heck knows what China really uses or used in their inventory :/.

 

It's a bit like talking about AIM-9R. It was never used operationally (not even sure if there was an experimental version) but if you didn't know any better you might demand that it be modeled. See what I mean?

 

Not if thats true: http://en.wikipedia.org/wiki/R-27_%28air-to-air_missile%29

 

Maybe someone just needs to do a "chinese addon" :smartass:

[sorcer3r]

The problem here is that while this isn't entirely un-plausible, why not convert to using R-77's altogether?

 

Agree.. maybe politics?

 

Another problem: Who the heck knows what China really uses or used in their inventory :/.

 

It's a bit like talking about AIM-9R. It was never used operationally (not even sure if there was an experimental version) but if you didn't know any better you might demand that it be modeled. See what I mean?

 

(almost an argument against the ka-50. Dont take him away from me ;) )

 

And also everyone is talking about the 120C and 27E but there are different 120C versions and it seems also different 27E versions. Anyway its interesting to read here.

[Teknetinium]

Su-27 should be able to track several targets as well in TWS, And INS guidance would not make the missile turn that hard until the missile have targets reflection witch would give the missile more speed in SARH mode.

 

Why are we arguing about it so much there is no TWS on Russian aircrafts and missiles are not compensated when they are poked down. Su-27 and MIG-29 fan boys really feel this since FC2, GG why is it so hard to say yes it should be implemented. Its not you call but you could at least agree since the feature is known.

 

Instead you tell me it was only for very specific models of MiG-29.

PLZ GG understand we don't have DCS fighters its not S or C or B in FC3.

It is updated FLANKER 2.0 :) (to be more correct F-15 2.0)

Edited December 4, 2012 by Teknetinium

[Kuky]

So what you are saying is that basically the 27ER is like a 120 fired in TWS but have to hold lock the whole time? If that's the case then that doesn't seem right. You have to lock the bandit in STT, which gives the guy a warning.

 

I am saying that firing R-27 has to be done in STT and naturally that will give targeted aircraft warning on RWR (as he's being locked - all radar energy directed at him) but since the missile itself is initially guided inertially, there should be no launch warning... lock still has to be maintained.

 

TWS with AIM-120 is different as you are not locking the bandit in STT so ge gets no lock warning and still only gets radar scan on RWR.

 

So not exactly the same... the difference is in both cases missile is guiding towards the target but in case of STT and R-27 there is clear warning on RWR that he is being targeted while TWS and AIM-120 (and should be also for TWS and R-77) attack is silent and you only get missile warning once it goes active.

 

This is both from readin the net, some common sense and some educated guesses based on what I know from styding physics.

[Kuky]

See IvanK's post. And really, there's plenty of data to say you'll be getting the warning, for one reason or another. It's sort of all over the place but it's findable.

 

yes, we both agree on this, question is what sort of warning should you get with STT / R-27 launch? I am of the opinion that only STT lock warning should be there because the SARH is guiding off the reflection of radar energy of the targeted aircraft, this radar energy comming from launchinf aircraft.

 

- Su-27 points all radar energy onto target aircraft

- Su-27 presses and holds the trigger, radar tada is transferred into missile and missile launches and goes into INS guidance

- Su-27 still needs to keep STT lock and when missile gets to INS point it switches to SARH guidance and starts homing onto reflected radar energy (the missile has its own radar energy receiver which can only receive but not send radar energy - what makes is SARH and not AR missile)

 

does this make sense?

[VAOZoky]

Yes the MiG-29S 2TWS should work like the F-15's with the R-77. This was a very specific radar upgrade to a few very specific models of MiG.

 

Well the problem is ED have put that very specific model of MiG in FC1/2/3... but forgot to put that very specific radar upgrade :)

[VAOZoky]

And btw why are we still arguing about MiG TWS when we both know ED's little secret :music_whistling:

[Teknetinium]

yes, we both agree on this, question is what sort of warning should you get with STT / R-27 launch? I am of the opinion that only STT lock warning should be there because the SARH is guiding off the reflection of radar energy of the targeted aircraft, this radar energy comming from launchinf aircraft.

 

- Su-27 points all radar energy onto target aircraft

- Su-27 presses and holds the trigger, radar tada is transferred into missile and missile launches and goes into INS guidance

- Su-27 still needs to keep STT lock and when missile gets to INS point it switches to SARH guidance and starts homing onto reflected radar energy (the missile has its own radar energy receiver which can only receive but not send radar energy - what makes is SARH and not AR missile)

 

does this make sense?

 

This would certainly make up for useless HOJ whit ERS since they don't have the legs at the moment.

 

And here is the point, in real life you would never tell your self this missile is bad so I pincer and wait, I know it will miss. You react different since you cant relay on your gathered intelligence as you can in games. That's why to emit this situation in a simulation you have to make missile deadly on both sides so the level of realism reaches in another point then just technical where the pilots learn how to exploit it after a while.

 

In FC1 ETs were compenseiting this senario witch apeard unrealistic but gave the simulation something in return.

Edited December 4, 2012 by Teknetinium

[Alfa]

I realy hope ED do something about Russian TWS, because in FC2 and FC3 it dosent do anything!!!!

 

Teknetinium I think you have misunderstood a few things in regards to TWS operation.

 

The TWS("SNP") mode does what its supposed to do in FC2 - the purpose of it is to ease pilot workload by automatically analising the tactical situation, pick the most appropriate target and prepare for its engagement.

 

In SNP mode the radar scans a sector and can simultaneously track up to 10 detected contacts. Based on the track data it determines which of the contacts will first enter its engagement parameters for the R-27R(and -ER in the case of Su-27/33) and starts to prepare for a missile launch - once the target falls within launch parameters, it will automatically switch to STT mode necessary for missile launch.

 

The advantage of the SNP mode is that it both scans and tracks at the same time unlike the pure scan modes("Encounter", "Pursuit" and "Automatic") and unlike with the pure track mode(STT), the opponent will only get warning on his RWS that you are preparing to attack him when the radar eventually switch to STT immedeatly before launch.

[Cali]

I am saying that firing R-27 has to be done in STT and naturally that will give targeted aircraft warning on RWR (as he's being locked - all radar energy directed at him) but since the missile itself is initially guided inertially, there should be no launch warning... lock still has to be maintained.

 

TWS with AIM-120 is different as you are not locking the bandit in STT so ge gets no lock warning and still only gets radar scan on RWR.

 

So not exactly the same... the difference is in both cases missile is guiding towards the target but in case of STT and R-27 there is clear warning on RWR that he is being targeted while TWS and AIM-120 (and should be also for TWS and R-77) attack is silent and you only get missile warning once it goes active.

 

This is both from readin the net, some common sense and some educated guesses based on what I know from styding physics.

 

Thx for explaining that, I know understand what you are talking about. But reading the internet on things like this is....kinda useless sometimes. They need hardcore facts on the matter and the internet doesn't cut it, nor does your studying physics, sorry but that's the truth. Although that sounds good, but anyone can make anything sound right.

[Alfa]

GG Can you please present some hard core documentation that R-27 missiles do not have INS guidance?

 

Radar guided versions of R-27 missiles(R-27R and R-27ER) have INS with radio command update. IR versions(R-27T and R-27ET) do not - they are "LOBL"(Lock On Before Launch) and their seekers must lock on to the target before they can be launched.

 

I have seens in few documentaries and some Australian Defence regional threats documents where they compare various US and Russian missiles and there is always mention that R-27 family of missiles in fact do have INS guidance, and if this is the case then there should be no misisle launch warning in RWR when R-27 is fired, the only warning you should get is when the missile switches from INS to SARH guidance.

 

Err what? - RWR warning comes from the aircraft radar switching to STT in preparation for launch of a SARH weapon. The missile itself doesn't emit anything neither at the point of launch nor at terminal stage SARH operation.

 

Yes, you need to keep an STT lock to fire the R-27 and not drop the lock, but the missile should launch in INS guidance first stage of flight to pre calculated point (same as 120's and 77's) the only difference between them is 120 and 77 should have capability of launch in TWS mode (no STT lock and no RWR lock warning) and they should all guide in INS guidance first untill in terminal phase where 120 and 77 switch to their own radar while R-27 needs to be guided by launching aircraft radar.

 

Yes although slight correction - when in terminal SARH operation, the R-27R is not "guided" by the launching aircraft radar. Its homing on target via its own radar seeker - the reason you need to keep lock on target is because SARH seekers don't have their own emitter and therefore needs the aircraft radar's target returns to home on.

[Teknetinium]

Teknetinium I think you have misunderstood a few things in regards to TWS operation.

 

The TWS("SNP") mode does what its supposed to do in FC2 - the purpose of it is to ease pilot workload by automatically analising the tactical situation, pick the most appropriate target and prepare for its engagement.

 

In SNP mode the radar scans a sector and can simultaneously track up to 10 detected contacts. Based on the track data it determines which of the contacts will first enter its engagement parameters for the R-27R(and -ER in the case of Su-27/33) and starts to prepare for a missile launch - once the target falls within launch parameters, it will automatically switch to STT mode necessary for missile launch.

 

The advantage of the SNP mode is that it both scans and tracks at the same time unlike the pure scan modes("Encounter", "Pursuit" and "Automatic") and unlike with the pure track mode(STT), the opponent will only get warning on his RWS that you are preparing to attack him when the radar eventually switch to STT immedeatly before launch.

 

"SNP" Do you mean guide a missile while scanning or be able to see missiles lunch parameters while scanning?

And what are your assumptions on if R-27 gives a lunch warning in inertial guidance or dose that not matter since you are in STT mode?

Edited December 4, 2012 by Teknetinium

[Alfa]

As to the INS business. INS in this regard (if indeed its fitted to the R27) would be just like a strap down platform providing inertial axis/stability type references to the missile not "INS navigation". It may also be used to provide acceleration G data for fuse arming post launch. I dont believe any Target coordinates are feed to the R27 before launch.... the INS is just used to tell the missile which way is up ... like a miniature Gyro ref system.

 

IvanK the R-27R/ER does have an actual INS, which is being fed target info prior to launch and updated via radio command after launch. Its using proportional navigation to guide the missile into engagment zone.

 

What you suggested sounds like an early AIM-7 system :)

[Kuky]

Radar guided versions of R-27 missiles(R-27R and R-27ER) have INS with radio command update. IR versions(R-27T and R-27ET) do not - they are "LOBL"(Lock On Before Launch) and their seekers must lock on to the target before they can be launched.

 

Yup I agree with that

 

Err what? - RWR warning comes from the aircraft radar switching to STT in preparation for launch of a SARH weapon. The missile itself doesn't emit anything neither at the point of launch nor at terminal stage SARH operation.

 

Sorry, made a mistake there, you are right, the RWR warning should be there only when STT lock is established but no distinguish when missile is actually launched.

 

Yes although slight correction - when in terminal SARH operation, the R-27R is not "guided" by the launching aircraft radar. Its homing on target via its own radar seeker - the reason you need to keep lock on target is because SARH seekers don't have their own emitter and therefore needs the aircraft radar's target returns to home on.

 

I think my wording was maybe off, essentially we are saying the same thing. SARH missile in terminal guidance phase is guided by the reflective radar energy (and this energy is courced from launching aircraft's radar)

[Kuky]

Thx for explaining that, I know understand what you are talking about. But reading the internet on things like this is....kinda useless sometimes. They need hardcore facts on the matter and the internet doesn't cut it, nor does your studying physics, sorry but that's the truth. Although that sounds good, but anyone can make anything sound right.

 

Reading off the internet can still be quite informative, it just depends how much of it you read and not just one source... radar energy and missile guidance and homing is still obeying lawys of physics so knowing some does help, then take some common sense into equation and you can make some pretty good educated guesses.

 

After all, who can open up a real R-27, AIM-120 and take some photos of its internals to present the only acceptable source of info? Well noone can, hence why we have to make educated guesses with things like this.

[GGTharos]

The radar switches to an attack waveform, and transmits an M-link. That should be a rather dead give-away for triggering a warning.

 

Sorry, made a mistake there, you are right, the RWR warning should be there only when STT lock is established but no distinguish when missile is actually launched.

[Alfa]

"SNP" Do you mean guide a missile while scanning or be able to see missiles lunch parameters while scanning?

 

"SNP" is the Russian word for TWS(Track While Scan) - scanning only provides simple information such as target bearing and range, while tracking also provides target heading and speed, which is necessary for calculating launch parameters. So its impossible to guide a missile in a scan mode. What I mean is scanning a sector for contacts, while tracking multiple known contacts to figure out which of these will first be "eligable" for engagement. :)

 

The possibility of attacking multiple targets simultaneously from TWS mode is basically down to the type of missile being used - its possible with ARHs, but mechanically scanned radars such as the N019 and N001 can only engage one target at a time(via STT mode) with SARH missiles and since ARHs wheren't available at the time the basic N019 and N001 were developed, there is no weapon's deployment function in SNP mode.

 

The MiG-29S has a modified version of the radar(N019M) that apparently has an extra SNP mode where two targets can be "bugged" and from which launch of R-77 can be performed directly(no need to enter STT).

 

And what are the assumptions on if R-27 gives a lunch warning in inertial guidance Alfa?

 

I don't know about launch warning, but the opponent will get a lock warning on his RWR because the N019/N001 needs to enter STT in order to launch an R-27R/ER and in that respect it really doesn't have anything to do with inertial guidance.

 

To be honest I don't really know what triggers a launch warning - if its down to the radar starting to transmit command update to the inflight missile, then this should also affect ARH weapons since they employ the same guidance method at initial stage of flight.

[GGTharos]

Su-27 should be able to track several targets as well in TWS, And INS guidance would not make the missile turn that hard until the missile have targets reflection witch would give the missile more speed in SARH mode.

 

INS has nothing to do with how hard the missile turns. You're connecting two different things with no logical reason to make the conclusion you've made.

 

GG why is it so hard to say yes it should be implemented. Its not you call but you could at least agree since the feature is known.

 

Actually just like Alfa said - the mode you're talking about is SNP and it is not used for actual weapon employment.

 

Instead you tell me it was only for very specific models of MiG-29.

 

I wasn't telling you anything, I was responding to Kuky and as usual, you weren't reading the entire context of what was being said. Within the aircraft set modeled in FC, the MiG-29S is the only Russian aircraft which could have used the TWS mode. And it was only some of those 29S'. Now there are newer models which do more, but FC models none of them.

 

PLZ GG understand we don't have DCS fighters its not S or C or B in FC3.

It is updated FLANKER 2.0 :) (to be more correct F-15 2.0)

 

Actually yes, it is the Su-27S(K). That is in fact the aircraft modeled by ED, based off of that aircraft's operating manual.

The F-15C in-game doesn't even do 1/10th of the stuff that the real F-15C (from 1988, BTW) does.

[GGTharos]

That would just light up everyone's RWR. There are very likely some situations that will trigger the RWR with TWS+Launch, but I think they're narrow and the circumstances they should occur at aren't simulated in FC anyway ... just IMHO.

 

then this should also affect ARH weapons since they employ the same guidance method at initial stage of flight.

[Kuky]

The radar switches to an attack waveform, and transmits an M-link. That should be a rather dead give-away for triggering a warning.

 

I don't quite buy that... this dead give-away attack waveform is the STT lock itself. I would think that if there was this M-link from launching aircraft to SARH missile then missile would be like beam riding missile (which its not) or it would have to have receiver pointing backwards to launching aircraft and I don't think this is the case.

 

I think instead the missile is flying towards target in INS guidance (no M-link with launching aircraft) with little to no manouvering in order to fly efficient flight path untill it's close enough for its own radar receiver to pick of reflective radar energy that is bouncing off the targeted aircaft and then starts guiding towards it.

[Alfa]

That would just light up everyone's RWR. There are very likely some situations that will trigger the RWR with TWS+Launch, but I think they're narrow and the circumstances they should occur at aren't simulated in FC anyway ... just IMHO.

 

Yup that was my point too - the only actual launch warning(separate from radar switching to attack mode that is) that I can think of would be something like what some dedicated ground attack aircraft/helicopters have - i.e. optical sensors detecting incoming heat sources(missile plume), but that is obviously very range limited and not an RWR function anyway :) .

[GGTharos]

I don't quite buy that... this dead give-away attack waveform is the STT lock itself. I would think that if there was this M-link from launching aircraft to SARH missile then missile would be like beam riding missile (which its not) or it would have to have receiver pointing backwards to launching aircraft and I don't think this is the case.

 

The ED guys have a pretty good idea, and we don't have their sources - most people do not.

 

I think instead the missile is flying towards target in INS guidance (no M-link with launching aircraft) with little to no manouvering in order to fly efficient flight path untill it's close enough for its own radar receiver to pick of reflective radar energy that is bouncing off the targeted aircaft and then starts guiding towards it.

 

The M-Link is generated the moment you launch the missile. It flies PN all the way to the target. INS is there only so that you can launch the missile beyond its seeker's capability. If the missile just flew stupidly to the activation point they'd find it sucks as much as an AMRAAM that does the same thing (happened for real!)

[Alfa]

I don't quite buy that... this dead give-away attack waveform is the STT lock itself.

 

Yes.

 

I would think that if there was this M-link from launching aircraft to SARH missile then missile would be like beam riding missile (which its not) or it would have to have receiver pointing backwards to launching aircraft and I don't think this is the case.

 

I think instead the missile is flying towards target in INS guidance (no M-link with launching aircraft) with little to no manouvering in order to fly efficient flight path untill it's close enough for its own radar receiver to pick of reflective radar energy that is bouncing off the targeted aircaft and then starts guiding towards it.

 

Kuky the R-27R/ER use INS + radio correction(datalink) after launch - inertial guidance without command update would be pretty useless as the INS at no point could take any post launch target manouvering into consideration, which in turn defeats the purpose of proportional navigation. So the radar does initiate an M-link at the point of launch and the R-27R/ER does have antennas(rectangular vanes on the seeker section) to recieve updates :) .

[Cali]

Reading off the internet can still be quite informative, it just depends how much of it you read and not just one source... radar energy and missile guidance and homing is still obeying lawys of physics so knowing some does help, then take some common sense into equation and you can make some pretty good educated guesses.

 

After all, who can open up a real R-27, AIM-120 and take some photos of its internals to present the only acceptable source of info? Well noone can, hence why we have to make educated guesses with things like this.

 

I didn't mean to say that the internet can't be right, like you said it can and does have credit info. I do what you said, look into more than one source and if enough things add up.

 

A little info on the 120

http://www.designation-systems.net/dusrm/m-120.html

http://www.fas.org/man/dod-101/sys/missile/aim-120.htm

http://www.ausairpower.net/amraam.html

http://www.nationalmuseum.af.mil/factsheets/factsheet.asp?id=1006

http://usmilitary.about.com/library/milinfo/affacts/blaim-120amraam.htm

http://www.ausairpower.net/skyflash-slammer.html

 

Just showing there is so much different info out there about things.

[IvanK]

Bandit takes STT lock for AIM7/R27R/R27ER shot ...... RWR goes "BEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEP"...... STT detected.

 

Pilot presses Missile release button/trigger.... "electrical launch" now occurs ....... " The radar will transfer to guidance waveform right away. The F-15 radar does the same thing for the sparrow with pretty good reasons (the seeker needs this waveform, and and has to be tuned to it at launch)."

 

RWR goes "BEEEEEP ..... BEEEEEP ..... BEEEEEP ..... BEEEEEP" i.e.Missile on the way ... technically its saying Guidance waveform detected... therefore missile on the way. Mechanical launch now occurs.... i.e. Missile comes off the rail. This all happening over "say" a 1-2 second period.

Edited December 4, 2012 by IvanK