Air-to-Air Missile Discussion

[schroedi]

F-15C doesn't have any sort of 'stealth' in-game or IRL.

 

In-game the fighter RCS values are the same.

 

7m2 IIRC.

 

Edit; Sniped by the Ghost.

 

For the F-117, too?

[GGTharos]

No, F-117 has a small RCS value.

[Frostie]

Frostie, there are also 4 different version of the R-77 doppler radar fyi... (found pictures on internet)

 

Monopulse radars are less prone to jamming and have a high degree of accuracy, very good reasons to use on active missiles.

[Sweep]

I think my memory dun goof'd there.

 

Saw 5m2 in some of the core-mod lua files (F-5E).

 

Thx for the correction. :thumbup:

[Frostie]

Not what I've 'been told. Certainly no radar can be literally immune to chaff: It's there, it has an RCS, the radar will see it regardless of what antenna arrangement you're using.

 

The 120B already had significant ECCM, all thanks to its re-programmable capability. If you can't eliminate 'seeing' chaff, find a way to get rid of its effects - there's plenty of ways to help the missile out:

 

The data-link from the carrier aircraft

The MPRF homing mode (aka pitbull), as MPRF helps reject clutter

Flight path shaping to either keep chaff out of sight OR to help separate it from the target

Track building to avoid confusion due to centroid changes or motion + CM ... and so on and so forth.

 

And then someone decides they'll use jaff, and maybe, just maybe you're back to square one.

 

But no one has jaff in this game anyway, so that's a non-issue :)

 

Yes but at what point does the decision that increased effectiveness against chaff for one radar set(ARH) makes it more effective compared to a different radar set eg. Fighter radars which also have algorithms to deal with clutter, ECCM and prf modes. This whole notion of 120C being chaff resistant whilst far more powerful modern dedicated radar sets are not seems skewed. There is a reason the 120 maintains its SARH capability.

[D4n]

Wait, ALL fighters in DCS have SAME RCS? lol? But then the MiG-29S radar is too weak in DCS, as it was developed IRL to detect jets like F-15C at 120km distance... I quote, MiG-29S radar (N010M Zhuk-M) "... has a detection range of up to 120 km vs a 5 m2 RCS target for the export variant, [and up to 10 targets tracked and up to 4 attacked at once in air-to-air mode.] The tracking range is 0.83 - 0.85 of the detection range."

[D4n]

Aren't the R-77 using monopulse radar then? (as it is better than Doppler according to you, Frostie)

[Sweep]

Wait, ALL fighters in DCS have SAME RCS? lol? But then the MiG-29S radar is too weak in DCS, as it was developed IRL to detect jets like F-15C at 120km distance... I quote, MiG-29S radar (N010M Zhuk-M) "... has a detection range of up to 120 km vs a 5 m2 RCS target for the export variant, [and up to 10 targets tracked and up to 4 attacked at once in air-to-air mode.] The tracking range is 0.83 - 0.85 of the detection range."

 

We're using the N019M in the MiG-29S, I think?

 

Looking it up, will edit in a sec...

 

Edit: Yeah, think that's right. N019M is the upgraded radar with 2 target track (TWS2 in-game)/guiding and (theoretical :D) R-77 capability.

Edited December 17, 2015 by Sweep

[D4n]

Can't find data about N019M on Google concerning 120 km range detection...

 

EDIT: I did. It says M version 80 km range. Then why does the HUD range go up to 120km range in DCS? That's weird.

Edited December 17, 2015 by DanielNL

[Frostie]

Can't find data about N019M on Google concerning 120 km range detection...

 

EDIT: I did. It says M version 80 km range. Then why does the HUD range go up to 120km range in DCS? That's weird.

Larger aircraft.

[GGTharos]

There's no SARH capability on the 120, and I don't see how you're coming up that SARH can be in any way, shape or form superior to ARH. It isn't now and never will be.

 

Modern radars are pretty good at rejecting chaff, but they don't share purpose with the missile's radar, be it SARH or ARH. And that purpose is to drive a collision course.

 

I don't see the point of this argument; it is a complete side-track, and not relevant to the current problem at hand at all. The choice of modeling is what it is; it can only be made more complex, but that isn't going to happen any time soon IMHO.

 

Got older missiles? They'll be more vulnerable. In some cases, by a lot (eg, consider that R-3S ... it should be eating chaff like no-one's business).

 

What should R-27's and AIM-7's be doing and why aren't they doing it like we believe they ought to?

 

Yes but at what point does the decision that increased effectiveness against chaff for one radar set(ARH) makes it more effective compared to a different radar set eg. Fighter radars which also have algorithms to deal with clutter, ECCM and prf modes. This whole notion of 120C being chaff resistant whilst far more powerful modern dedicated radar sets are not seems skewed. There is a reason the 120 maintains its SARH capability.

[Sweep]

(eg, consider that R-3R ... it should be eating chaff like no-one's business)

 

See quote, not trying to be an expletive of any sort. :)

[D4n]

Does the word "expletive" even exist? (gotta research it's meaning if so), common English please, we have DCS fans from all over the world here... ;)

[IASGATG]

Chaff isn't 100% effective against SARH missiles though. Chaff + maneuver is effective against missiles. The missiles are beamed against a very highly dense chaff environment. (~25 chaff at tracking loss)

 

I've attached the testing I've done as well at similar ranges at look up only and the missiles will miss when off aspect in a high chaff environment. They will hit even beamed with active chaff in the seeker FOV.

 

The only question here is how much chaff is reasonable to distract the seeker head.

 

Test Track

[fltsimbuff]

Does the word "expletive" even exist? (gotta research it's meaning if so), common English please, we have DCS fans from all over the world here... ;)

 

It looks like autocorrect bit him, I am guessing he meant "expert"?

 

I'd give you some examples of expletives, but the mods would not like that ;)

[Sweep]

No, that was intentional.

 

I didn't want to come off like a you-know-what hole.

 

IDK, I've been dealing with sensitive people on other sites lately. :D

[Frostie]

See quote, not trying to be an expletive of any sort. :)

 

Not trying to be an *expletive* or [foul word meaning backside hole] but you should have typed it out clearer. ;)

[Sweep]

You expletive.

 

I agree :D

[Beamscanner]

Can't find data about N019M on Google concerning 120 km range detection...

 

EDIT: I did. It says M version 80 km range. Then why does the HUD range go up to 120km range in DCS? That's weird.

 

The max detection range on the display represents a value chosen by the engineers that takes into account the radars maximum unambiguous range and the max detection range vs large RCS targets. like bombers...

 

When comparing radar detection ranges you want to use a constant value for the targets RCS.. such as 1 square meter.

 

The APG-63 is described as detecting 1 square meter targets past 80nm.. Comparably the modified SLOTBACK (or N019m) on the MIG-29S will detect that same target at less then half that range..

 

The APG-63 is larger then the N019.(higher gain->narrow beam->more energy on target->also means more energy received from that direction in space->more sensitive on receive)

 

It also uses a superior mono-pulse array(planar array vs twisted caisgrain), for higher quality angle tracking.

 

It also sported digital signal processing techniques(including digital doppler filters, giving it that "clutter free" radar display). The N019 only used digital processing for Tracking AFAIK, and was made up of vacuum tubes vice transistors..

 

Russian radar technology lags behind the west by more than 10 years.. More so, if strictly compared to the U.S.

[SDsc0rch]

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

[Chizh]

I wonder if the R-77 easily looses the target as soon as F-15C pops few chaff, while AIM-120C nearly every time hits MiG-29 even though popping tons of chaff. Is there difference between these two missiles in current DCS?

Yes.

The 120C has more resistance for countermeasures than 120B and 77.

R-77 has same level of CCM as 120B.

 

Also, are R-77 and AIM-120C acceleration, burn-time/speed and max G values quite different?

Yes.

[vicx]

When people post Tacview playbacks of simulation gone bad ... it isn't the aerodynamic perf that has people face palming. It seems like the modelling for guidance and counter-measures is not heading in the right direction.

[*Rage*]

Chaff isn't 100% effective against SARH missiles though. Chaff + maneuver is effective against missiles. The missiles are beamed against a very highly dense chaff environment. (~25 chaff at tracking loss)

 

I've attached the testing I've done as well at similar ranges at look up only and the missiles will miss when off aspect in a high chaff environment. They will hit even beamed with active chaff in the seeker FOV.

 

The only question here is how much chaff is reasonable to distract the seeker head.

 

Test Track

 

A 30 deg offset causing most missiles (75%) to miss in look up is ridiculous.

 

Edit: Sometimes they dont even track to the chaff!!! They just get lost in the 'air clutter'

 

I see your track and post you another two. Taken from the ER chaff threads. Im also convinced in a busy MP server the ERs/ETs track even worse (even without visible warp/lag/bad pings) than in test conditions.

comedy xD Eagle stall fighter TACVIEW.rar

Tacview-20151109-130824-DCS.txt.rar

Edited December 18, 2015 by ///Rage

[Ktulu2]

Edit: Sometimes they dont even track to the chaff!!! They just get lost in the 'air clutter'

 

Ok, I thought the R27 being weaker was ok...that's on an other level :lol:

[*Rage*]

Why was my bug report merged into a discussion? Any comment from the Devs?

 

Chizh?