R-27/R-27ER Max Closure Speed?

[ruddy122]

Hi Everyone,

 

I've noticed this while I was doing a head on intercept with a MiG-25.

 

Target Speed 1350 Km/h

My Speed 1300 Km/h

 

Total Closure Speed 2600 Km/h

 

I was getting an intermittent launch authorized message as I was approaching min range.

 

My question is there a max closure speed for launching and R-27/R-27ER and if we do why?

 

Thanks,

[inSky_1911CFZS]

R-27 missile's maximum speed is about 2100kts(3780km/h),max closure speed should higher than this(See some Surface-to-Air Missile performance data)

[ruddy122]

I don't believe its a missile performance issue but a radar tracking/guidance issue.

 

I posted this trk file in the Best Landings thread http://forums.eagle.ru/showthread.php?t=142355&page=4 and it's the third group with the MiG-25

 

I don't know if its a bug or a true radar guidance limitation

 

Thanks,

Edited May 3, 2015 by ruddy122

[Ironhand]

I don't believe its a missile performance issue but a radar tracking/guidance issue.

 

I posted this trk file in the Best Landings thread http://forums.eagle.ru/showthread.php?t=142355&page=4 and it's the third group with the MiG-25

 

I don't know if its a bug or a true radar guidance limitation

 

Thanks,

I'll have time to check the track this afternoon. But, if you were getting close to launch mins and the other aircraft or you were maneuvering in any way, that might be why it was happening. On one heading he was within launch parameters, while on another he wasn't. Just a thought.

[Ironhand]

Just watched the track. Unfortunately, it doesn't play back correctly and you are destroyed by the 2nd MiG in the group. I did notice that, when you were taking on the first MiG, you lost LA very briefly once. Not sure why. In the case of the 2nd MiG, you only lost it when you launched your last long range stick and the next selected missile was an R-73. But there the target was still too far away for LA. Unfortunately, I also can't view your landing, since the MiG-25 destroyed you in the playback.

[ruddy122]

Ironhand,

 

I'll try to create an updated track file to see if it does it again.

 

Thanks,

[ruddy122]

Here is an updated .trk file with a MiG-25 Intercept

 

Mission Details

 

Altitude above 10,000 m

 

Combined Closure Rate 2400 Km/h

 

Locks and receives "Launch Authorized" steady at 50 Km

 

At inside 45 km "Launch Authorized" starts flashing.

 

Switched to R-27ET (IR) to attack bandits

 

Hope this helps. I think it may be a radar guidance limitation for SARH missiles but I'm not sure.

 

Thanks,

Su-27S-Foxbat Intercept.trk

[combatace]

Here is an updated .trk file with a MiG-25 Intercept

 

Mission Details

 

Altitude above 10,000 m

 

Combined Closure Rate 2400 Km/h

 

Locks and receives "Launch Authorized" steady at 50 Km

 

At inside 45 km "Launch Authorized" starts flashing.

 

Switched to R-27ET (IR) to attack bandits

 

Hope this helps. I think it may be a radar guidance limitation for SARH missiles but I'm not sure.

 

Thanks,

 

 

First of all, I don't understand why did you set the scan range to 100Kms and elevation 2 kms when you set your HUD range to just 50Kms. You had targets at range more then 100 and 1km below you at the time of final intercept.

Secondly, when your first target was 50-60Kms away you there was a change in your lock, your RADAR lock got turned off and your EOS started tracking. Now, I don't know if you turned it off by yourself or it got turned of by itself and R-27ER won't be having any launch on EOS lock and that is why you were getting flashing LA.

Also, for head-on engagement you can use HI PRF for higher detection range rather then ILV (interleaved).

Edited May 4, 2015 by combatace