IR AIM-4 constant near misses

[Sheriff001 397]

Hi everyone. Recently, I've been using the AIM-4 frequently, mainly with the F-102A, but also with the Voodoo and F-106. SARH Falcons seem to track and hit unerringly, however IR AIM-4s will track the target until the last moment, then it will just miss. A proximity fused missile might have detonated, but the AIM-4 is impact fused. Here are two sequential screenshots, taking within fractions of a second of an AIM-4C being fired at a QB-17 target drone. Similar results were evident when firing at QB-47 Stratojets. The missiles were fired at near maximum range (indicated on the radar scope) to give time for the missile to arm (2 seconds) at 6 o'clock.

 

Here is the AIM-4D_data.ini

 

[WeaponData001]
TypeName=AIM-4D
FullName=AIM-4D Falcon  IR
ModelName=AIM-4D
Mass=61.000000
Diameter=0.163000
Length=2.020000
AttachmentType=USAF,TAIWAN,JAPAN,GREECE
SpecificStationCode=AIM4
NationName=USAF
StartYear=1963
EndYear=1988
Availability=2
BaseQuantity=24
Exported=TRUE
ExportStartYear=1963
ExportEndYear=1988
ExportAvailability=2
WeaponDataType=1
RailLaunched=TRUE
RocketPod=FALSE
Retarded=FALSE
Streamlined=TRUE
FinStabilized=TRUE
SpinStabilized=FALSE
HasGrowl=TRUE
EffectClassName=SmallMissileEffects
ReleaseDelay=0.000000
WarheadType=0
Explosives=3.400000
FusingDistance=0.000000
ClusterBomblets=0
ClusterDispersion=0.000000
GuidanceType=10
Accuracy=75
MaxTurnRate=15.000000
MaxLaunchG=4.000000
LockonChance=75
LaunchReliability=80
ArmingTime=2.000000
SeekerFOV=3.400000
SeekerGimbleLimit=28.000000
SeekerTrackRate=16.500000
SeekerRange=10200.000000
MinLaunchRange=1500.000000
MaxLaunchRange=10200.000000
Duration=18.000000
CounterCountermeasure=50.000000
NoiseRejection=20.000000
CapabilityFlags=0x00000240
BoosterStart=0.000000
BoosterDuration=1.850000
BoosterAccel=54.650002
BoosterEffectName=MissileFireEffect
BoosterSoundName=Missile
BoosterNodeName=
BoosterPosition=0.000000,-0.984000,0.000000
SustainerDuration=0.000000
SustainerAccel=0.000000
SustainerEffectName=
SustainerSoundName=
SustainerPosition=0.000000,-0.984000,0.000000
InFlightEffectName=MissileInFlightEffect
InFlightSoundName=
ReleaseAnimationID=1
EODisplayFlags=0
 

[+daddyairplanes 10,123]

well the Falcon was a VERY unreliable missile to begin with. but against a non manuevering B-17 drone that is interesting that you got no hits. also keep in mind it was contact fused so if the Fort did move at all and the missile missed by as little as 1 ft, there would be no boom.  unfortunealtly the fighters you listed dont allow you to pull a GEN Olds and swap for Sidewinders.

[Snailman 517]

It must be the problem with all Rear 60 Aspect missiles, i suspect... 

I have similar with the early AA-2 Atoll but AIM-9B and israeli missiles do the same. Even if all other features are the same, changing the seeker aspect from Rear 60 to Rear 180 degrees means a difference between black and white. Besides Rear60's are next to impossible to get a growl on a turning target, they lose tracking almost always the target starts to maneuver and they can't keep tracking of a constantly turning aircraft.

 

Also be careful that missile duration must be long enough for the missile to run through its max range. When I fixed the AA-3 Anabs and RS-1 Alkalis, they has such problems. The range value allows you to fire, but the missile stops working prematurely due to the duration value. At first I suggest you to give more than 18 seconds

Edited October 16, 2013 by Snailman

[Sheriff001 397]

The missile duration sounds like a good place to start. I've changed the durations to 32 seconds (consistent with the AIM-4F/G Super Falcons). That change may well have an effect, as the missiles go ballistic at the last few moments of flight. Only the AIM-4B is Rear 60. All other IR Falcons are rear 180. In the main, I use the AIM-4A (SARH), AIM-4C (IR), AIM-4D (IR), and AIM-26 (SARH) in the F-102, AIM-4D in the F-101B, and AIM-4F/G in the F-106.

[Sheriff001 397]

Missile duration doesn't seem to be the problem. I fired six AIM-4Ds, all either dead astern, or close to it. All went ballistic at the last moment. I varied the range, from maximum to the minimum I believed would allow the missile time to arm. None of the shots took close to 30 seconds from launch to missing the target.

I will try increasing the Seeker POV.

[Sheriff001 397]

Increasing Seeker POV had no effect. 6 misses out of 6 missiles. I even saw one pass within 5 metres of a QB-47. Now uncaging the seeker.

[Snailman 517]

I know what it is like(  Try a working missile, and compare the differences between them... have to debug the values one at a time. Its a real pain but there is no other method(

[Fubar512 1,350]

Ah yes, the Aim-4, otherwise known as the $386,000 turn signal.

[Snailman 517]

I did some tests for you....  Unfortunately I onlyhave the stock AIM-4D which is a station specific one, i found only the stock F-4E which can carry it.

 

Stock AIM-4D has seeker range of 9.6 ... and is Rear180 aspect.

 

I first got a growl at about 6.9-7.2 .   When I fired them, i found that they are very fast moving ones. Considering the arming time and delay, I can say they are useless within 3kms... because it has almost no time and chance to maneuver  before it reaches target. Indeed it is an anti-bomber missile not for dogfighting...

 

I fired 10-12 missiles from the F-4E  at Tu-16 badger-As   from straight behind. I experienced no problem with detonations, some missiles have failed to lock on, however, due to reliability value.

 

 

 

Edited October 16, 2013 by Snailman

[Snailman 517]

I made a copy of AIM-4D in the weapon editor and pasted the ini data you wrote above. "AIM-4D Test" missiles performed exactly the same. Usage closer than 3.5km is not recommended. Otherwise no anomalies... Happened twice, when the Tu-16s were too close to each other the missile could not decide which to track, and finally lost both. But I guess its normal...

 

 

 

 

[arthur666 65]

I believe that SupGen did some research and discovered that the AIM-4 was not inherently inaccurate, but rather was unreliable being used by F-4's in Vietnam when it was originally designed to be used by the different fire-control system of the F-102/106.  I downloaded his latest F-102 pack and use it over the RAZBAM plane, and the missiles in that pack work satisfactorily against large targets when using good launch parameters.

 

I have to doubt that if they were indeed that unreliable, the USAF would have kept them in service well into the '80s.

Edited October 16, 2013 by arthur666

[MigBuster 2,884]

Yes - the setup on the F-4 was totally inadequate for any kind of close in combat.

 

Data I have shows a >0.90 PK for 2 missiles fired rear aspect against a level subsonic bomber (expect no CM) for the AIM-4D.

 

 

So yeah it was still **** relatively speaking

[+daddyairplanes 10,123]

 

 

I have to doubt that if they were indeed that unreliable, the USAF would have kept them in service well into the '80s.

main reason for that was they were the sole missile armament for the F-106. given it was designed for that system and the pilots worked exclusively with it most Six pilots report favorably on it especially in the later years when they had worked the kinks out and KNEW the system. but i am willing to bet if they could have modified to use Winder and Sparrow they would have changed in a heart beat. also their mission set was what the Falcon was designed for... to intercept Bear and Badger bombers off the US coast.  AND they still swapped from the Genie to the gun with Project Six Shooter....

[+ravenclaw_007 7,622]

there may be a difference what game/patch you use , i ustill use nov2011 patch and i get some reasonable result with the AIM-4D i made , in fact i get the same hit rate as if i use the AIM-9B around 6 hits from 10 missiles fired

 

f you like to get a better hit rate you have to adjust the Accuracy=75 and LockonChance=75 as well as the SeekerFOV and SeekerGimbleLimit ( i changed them already to get better results )

 

the original AIM-4D has a max distance from 9.7 km (6 miles) and a rocket burn time of 1.85 sec (BoosterDuration=1.850000) so changing the  BoosterDuration only gives you a longer flight time  but the missile will explode as soon as it reaches the MaxLaunchRange  anyway so no point in changing this parameter

[Snailman 517]

Data I have shows a >0.90 PK for 2 missiles fired rear aspect against a level subsonic bomber (expect no CM) for the AIM-4D.

What I tested right now reflects that. If parameters and rules are kept, it can provide a kill.

 

Same as RS-2US (Alkali-B) could also provide a kill IF all those launch parameters are kept. R-3S is a different story however, because Rear 60 aspect missiles are next to useless in this game.

AA-2 Atoll could perform as it was expected... when used correctly. Just remember the difference between performance of VPAF and Arab league pilots

 in fact i get the same hit rate as if i use the AIM-9B around 6 hits from 10 missiles fired

 

How can you do that? With unlimited ammo, I did tests, and my hit rate with AIM-9B  and AA-2  are below 1%  from 200+ launches.  That very same for Shafrir and other Rear 60's too..   The target AI plane flies in a slight turn, in circle, that prevents me  from lock, and even if I can lock the missile loses the target almost all the time.  Not because of turn rate or seeker head... and yet there were no CM present.

[+ravenclaw_007 7,622]

 

How can you do that? With unlimited ammo, I did tests, and my hit rate with AIM-9B  and AA-2  are below 1%  from 200+ launches.  That very same for Shafrir and other Rear 60's too..   The target AI plane flies in a slight turn, in circle, that prevents me  from lock, and even if I can lock the missile loses the target almost all the time.  Not because of turn rate or seeker head... and yet there were no CM present.

 

first as i metion above i´m still on SF2 merged nov2011 patch , i only launch the missile on a target if the target flys in a almost straight line so i can have a good lock on and i dont launch a missile on a max distance

 

you are right as soon as the target starts to manoeuvre the missile will loose the lock on

[+Crusader 2,082]

http://combatace.com/topic/54727-no-kill-like-a-missile-kill/?do=findComment&comment=401555

[Snailman 517]

first as i metion above i´m still on SF2 merged nov2011 patch , i only launch the missile on a target if the target flys in a almost straight line so i can have a good lock on and i dont launch a missile on a max distance

 

you are right as soon as the target starts to manoeuvre the missile will loose the lock on

 

Well I have July2012....  Yes, if the target flies straight... IF the AI would not spot the incoming missile. But unless they are bombers, they almost always spot it and evade.... and they dont even drop CM...

What was the historical hit rate of such missiles?  I'd bet not 1% in a clear situation

[+ravenclaw_007 7,622]

here are 2 pictures showing it , i only launch with the target in the gun-cross and within the limits , result 4 missile fired and 3 hits (targets are QF-100D)

 

i think the problem is more on the game if you are with SF2NA or SF2 with the latest patch , there are some items changed to make the missile behave more "real"

 

Edited October 16, 2013 by ravenclaw_007

[+Crusader 2,082]

http://combatace.com/topic/54727-no-kill-like-a-missile-kill/?do=findComment&comment=401555

And regarding AIM-4D  min launch range, the "shiny brochure"-claimed min range was 2500 ft  = 760 meters, but

during testing the min range for successful shots was not under 5000 ft = 1520 meter  (source: "Clashes", Michel)

Complete firing cycle from trigger pull to missiles off the rail was 4.7 seconds ( for ReleaseDelay= )

[Snailman 517]

For me, AIM-4 was ok... like Alkalis... but Rear60 Sidewinders and Atolls.. and Shafrirs... useless. When I change them to Rear180 they come to life immediately. I also suspect, SF2 later patch messed this up...

 

here are 2 pictures showing it , i only launch with the target in the gun-cross and within the limits , result 4 missile fired and 3 hits (targets are QF-100D)

 

i think the problem is more on the game if you are with SF2NA or SF2 with the latest patch , there are some items changed to make the missile behave more "real"

 

Yes, and AIM-4D is Rear 180 aspect. This also gives proof to what I say. Sidewinders are all Rear180 or better, xcept B. AA-2D Atoll-B is also rear180. Alkalis are SAHM and they work like they should. So only Rear60 IRM's suck but to such level they are next to useless. Was it like this before SF2 NA??

Does anyone have real life hit percentage statistics?

[Sheriff001 397]

I'm using the July 2012 version. I did obtain two hits out of six, on targets at approximately 5 NM. They didn't go down (QB-17s rarely do!) ,but they hit. Dropping the range at which I fire to 3-4 NM has a good effect.

Real life stats for the AIM-4 are hard to come by. I tend to discount the stats from VIetnam, as the missile was being used improperly. I have no information for the Greco-Turkish War of 1974 (F-102s on both sides). The intended combat use of the AIM-4, intercepting Soviet heavy bombers, never took place.

[Z09SS 21]

I found a great pdf on the AIM-4 once, and promptly lost it.

 

Found it again!

 

http://www.scribd.com/doc/62917699/The-Hughes-Falcon-Missile-Family-USA-2010

[Sheriff001 397]

Yes, I have that PDF. Here is a video on the MG-10 FCS for the F-102A. What I don't understand is that the everything tracks properly until the last moment.

 

http://www.youtube.com/watch?v=nhokCggffLg

 

Here is a screenshot from just before an AIM-4D went ballistic - tracking nicely towards the port outboard engine of the QB-47.

 

 

 

 

Here's the view from the cockpit at time of firing. I kept pace with the QB-47, and fired four shots from dead astern, about 3 NM range, good tone, optical sight on target, straight and level flight. All did the same thing. I am starting to think this is something deeper than missile settings. For diagnostic purposes, I set the accuracy to 99, with absolutely no effect on in game performance.

 

 

 

I should point out that this is being done in the Range terrain. In the Bering Straits terrain, I was able to hit 3 out of 5 missiles on Tu-4 bombers. I am not sure if there is a causal relationship between terrain and missile accuracy.

[Sheriff001 397]

I'm going to try this against QF-100s. The reason is that the missiles appear to have been tracking the engines of the target. With a QB-47, even the slightest error will result in a complete miss. With a QF-100, I may have a little more margin for error.