Question Regarding R77

[Essah]

Been practicing flying Su33 and Especially MiG29S against 2 and 3 opponents in simple quick scenarios I set up in the mission editor and then study the tracks in TacView to learn from mistakes and see what could be done differently

 

I noticed quite often while using R-77 (Which is a Russian ARH type missile) they would stop tracking their target, change direction back to their initial launch bearing and go ballistic or target a different aircraft than the one I initially launched the missile against.

Of course I initially thought this was due to me disengaging lock too early before the missiles own radar picked up the target I had locked on to at first, but then at one point I noticed it happen when the missile was less than 2 seconds from impact on its target which leads to my questions

 

Why does R-77 change or lose target suddenly? Is it because you can Doppler-notch the missiles radar as well. if so why does the missile not go ballistic instantly but rather change direction back to the one it had at launch moment?

Does the missile maybe go for the largest radar cross section available or something like that rather than initial target?

 

and a little side question, what is the approximate locking range for the Radar in the R-77 Missile?

 

Hope someone can help

[EtherealN]

Is it because you can Doppler-notch the missiles radar as well.

 

Of course you can. There's nothing magic about the radars in an ARH. ;)

 

if so why does the missile not go ballistic instantly but rather change direction back to the one it had at launch moment?

Does the missile maybe go for the largest radar cross section available or something like that rather than initial target?

 

Hard to say without tracks to see the specific situation, but an active radar missile that lost it's target is essentially the same thing as a heater that lost it's target - it'll fall in love with whatever shows up next. I've never observed them returning to a launch heading after losing lock, only go ballistic.

[Case]

Why does R-77 change or lose target suddenly? Is it because you can Doppler-notch the missiles radar as well. if so why does the missile not go ballistic instantly but rather change direction back to the one it had at launch moment?

 

Most likely the AI plane you are fighting turned into the notch and started dumping chaff. When this happens the missile stops tracking the plane and tracks the chaff instead, hence the change in direction (though not the direction at launch).

[Essah]

Most likely the AI plane you are fighting turned into the notch and started dumping chaff. When this happens the missile stops tracking the plane and tracks the chaff instead, hence the change in direction (though not the direction at launch).

 

sounds likely, I just guessed it was the initial bearing it returned to, not chaff.

I remember one incidence while watching the tacview track where the missile was only moments from impacting when it suddenly turned about 80 degrees to the side and went ballistic, the plane was flying perpendicular to the missile but had only done so for a few moments.

[GGTharos]

The missile follow proportional navigation. It tries to freeze the LOS rate of its target at zero, thus always leading it.

 

Chaff's speed is essentially zero, and as such the missile takes a sharp turn to intercept.

[RIPTIDE]

I've never observed them returning to a launch heading after losing lock, only go ballistic.

One exception. For R-77 active missiles that have not reached homing phase yet, if they loose launch craft guidance they will then turn to a pure pursuit onto the ECM, if there was music there at launch time (but within burn through limits.) Same happens with the likes of ER.

Edited August 22, 2011 by RIPTIDE

[combatace]

Been practicing flying Su33 and Especially MiG29S against 2 and 3 opponents in simple quick scenarios I set up in the mission editor and then study the tracks in TacView to learn from mistakes and see what could be done differently

 

I noticed quite often while using R-77 (Which is a Russian ARH type missile) they would stop tracking their target, change direction back to their initial launch bearing and go ballistic or target a different aircraft than the one I initially launched the missile against.

Of course I initially thought this was due to me disengaging lock too early before the missiles own radar picked up the target I had locked on to at first, but then at one point I noticed it happen when the missile was less than 2 seconds from impact on its target which leads to my questions

 

Why does R-77 change or lose target suddenly? Is it because you can Doppler-notch the missiles radar as well. if so why does the missile not go ballistic instantly but rather change direction back to the one it had at launch moment?

Does the missile maybe go for the largest radar cross section available or something like that rather than initial target?

 

and a little side question, what is the approximate locking range for the Radar in the R-77 Missile?

 

Hope someone can help

 

Its a problem with sim dynamics, just except it and get going. Its just not happens with R-77 it happens with all radar guided missiles.

[golfsierra2]

and a little side question, what is the approximate locking range for the Radar in the R-77 Missile?

 

Hope someone can help

 

From my observations, I would say between 8 and 5 km, depending on the situation (aspect, target size etc.)

[Essah]

One exception. For R-77 active missiles that have not reached homing phase yet, if they loose launch craft guidance they will then turn to a pure pursuit onto the ECM, if there was music there at launch time (but within burn through limits.) Same happens with the likes of ER.

 

seeing this reminds of a different question i had regarding missiles. slightly off topic but still related.

 

Ive noticed that Home-on-Jam R-27R/ER Missiles become autonomous if aircraft guidance is lost.

I thought this was a game innacuracy but maybe not? If not, then using Jammers against enemies armed with R-27R/ER is actually doing yourself a favor by enabling your opponent to launch autonomous missiels at you.

 

I thought R-27 was completly dependent on Aircraft guidance even in HOJ.

[EtherealN]

HOJ-shots are extremely inefficient kinematically though; since they're doing a pure pursuit they don't have any optimisation on their trajectory.

 

But yes, people who fly with jammers constantly on should be shot. :P

[RIPTIDE]

seeing this reminds of a different question i had regarding missiles. slightly off topic but still related.

 

Ive noticed that Home-on-Jam R-27R/ER Missiles become autonomous if aircraft guidance is lost.

I thought this was a game innacuracy but maybe not? If not, then using Jammers against enemies armed with R-27R/ER is actually doing yourself a favor by enabling your opponent to launch autonomous missiels at you.

 

I thought R-27 was completly dependent on Aircraft guidance even in HOJ.

The chance of a R-27ER hitting you in HOJ is not high. But there have been and will be spectacular exceptions. :D

[Cali]

HOJ-shots are extremely inefficient kinematically though; since they're doing a pure pursuit they don't have any optimisation on their trajectory.

 

But yes, people who fly with jammers constantly on should be shot. :P

 

This is a double edge sword for them, since burn-though is about 25nm. That is still plenty of time to plan your move. Regarding the R-77, I have seen a lot of people flying the Su-27/33 in a few servers fire them and think they will hit. I don't know if they know but they have to hold lock until the missile picks up the target also. It is nice to get a kill when people leave their jammer on from 30-35 miles away. Most of the time they have no clue that a missile is inbound and they fly right into it.

[Pilotasso]

HOJ is largely pointless in the current patch of FC2. You get much better results from using tactics to get closer.

[Alfa]

...and a little side question, what is the approximate locking range for the Radar in the R-77 Missile?

 

From memory the R-77's ARH radar seeker(9B1348 ) is stated to have an acquisition range of some 16 km against a target RCS of 5 m2.

[golfsierra2]

From memory the R-77's ARH radar seeker(9B1348 ) is stated to have an acquisition range of some 16 km against a target RCS of 5 m2.

 

IRL. In FC, you can see in TacView when the R-77 suddenly changes heading towards its target. From my observations, it never happened exceeding 8 km range. Maybe 10 at best, but not 16 like IRL.

[Alfa]

Yes IRL - dunno about the game.