AIM-7 Performance

[HawkDCS]

First of want to thanks ED and others for an incredible module. This is really going to be an amazing A/C once all the systems are in place.

 

I wanted to bring up the Aim 7M performance? I have been shooting at SU25s and other A/C since we don't have 120 yet. That being said either the missiles lose lock at last second or ignore target completely. This can be seen in several YT videos including Grim Reapers. Is this a bug? I am in STT follow the steering dot and last few seconds of flight they just turn some random direction. Even on non maneuvering targets. Once in awhile they hit but even firing at friendlies even C130s on terminal portion of flight they will just skew off some crazy direction or fly right past while I still have good lock on STT. I would say this happens 3/5 times. They aren't getting lost in Ground Clutter etc these are clean high altitude shots going haywire.

 

My second gripe is shown in Wags Aim 7 tutorial video. If you watch the video of him engaging the target he doesn't get an RNE until 5NM. This is at Angels 23 and 950Kts closure? The 7M is known to be over a 35Mi missile. I know this is a best case max range but 5Mi with 950Kts Vc??? I have missed enemy bombers at 7Mi with this missile at high altitude??? From my experience this missile is useless past 10 miles and many times it fails even on non maneuvering targets at less then 10Nm. I just did some tests tonight at Angels 30 when trying to hit an E3 we were co alt I have 300Kts closure and fired at 7Mi missile ran out of energy before it even got there lol. I know you can fire long before RNE but it misses so much of the time at this point theres no reason too.

 

I understand missiles aren't death rays and alot of factors play into their range. That being said the ranges I have to be at for the Aim7 in the 18 I might aswell use Aim 9s cause I am basically in range.

Edited June 2, 2018 by HawkDCS

[Chrissel]

I would've asked the same question as Shadow KT. But my English skills aren't so good to write a long explanation like yours.

I'm having the same "issue".

I don't know the specifications of the Sparrow, but I thought it would be "better" than the S530D of the Mirage. (I should check it out.)

[Belphe]

I was waiting for someone to start a thread about this as I wasn't sure if it was me or the SIM..

 

I have the exact same experience! I launch 4 7Ms one by one and NONE of them even follow the target that's 7nm away!

 

Please tell me its a bug and not the actual Sparrow performance..

[HawkDCS]

Thats what I don't know. I usually have OK performance with them in 15. They don't just fail to track and go flying off.

 

That being said the 15 is alot faster then the 18 so I imagine I am giving them alot more range since M1.5+ is no biggie in 15 and 18 takes ages to even get 1.2 etc.

 

I am going to build a test mission tomorrow with 15 and 18 and 7Ms and see what the results are. Just same targets same launch speeds and see what I get.

 

That being said I have noticed some bugs with F18 RDR. Many times I will STT lock and the steer cue will be edge of the hud so I turn that way and it will jump to opposite side and back like the radar cant figure out target bearing. Also it seems if you turn at all when you hit the TDC lock button the radar just loses the target completely. Seems like it takes the RDR a bit when you hit TDC Lock to actually lock the target like its thinking and if you move at all for these few seconds even gentle bank it just loses the lock and u have to hit unlock and start over.

Edited June 2, 2018 by HawkDCS

[Bravo]

The most common version of the Sparrow today, the AIM-7M, entered service in 1982 and featured a new inverse monopulse seeker (matching the capabilities of Skyflash), active radar proximity fuse, digital controls, improved ECM resistance, and better low-altitude performance. It was used to good advantage in the 1991 Gulf War, where it scored many USAF air-to-air kills. Of 44 missiles fired, 30 (68.2%) hit their intended targets resulting in 24/26 (54.5%/59.1%) kills. 19 kills were obtained beyond visual range.

 

- Source Wikipedia

So from this we get that they aren't the best missiles in the world, but I have been unable to reproduce a BVR kill with the AIM-7M or AIM-7F from a Hornet yet (Even though I am using the Rift).

But I must admit that it might be something I am doing wrong.

[Shadow KT]

It is all EA at the end... they've said that they will work on the missiles, nothing is final. I still haven't fired any in the Hornet, but ....

 

We can start bitching when it is "stable" and it doesn't work

[Bravo]

I found the bug! Its the engine of the missile.

It never reaches MACH 4 nor does it sustain Power for very long.

The engine performance is more akin that of a SideWinder.

 

Edit: It might be the drag that isnt correct as well, in either case the missiles range is WVR.

Edited June 2, 2018 by Bravo
Edit

[HawkDCS]

Ya I noticed at about Angels 24 it was only getting up to about 1400KTS but I didn't know if that was KIAS or TAS etc. I don't know if it actually does Mach 4 at lower ALTs either maybe its only at FL400 or something.

[Kelevra9987]

AIM-7 Performance is off

 

So today I tested our only BVR option as of now. The AIM-7 Sparrow.

 

According to Wikipedia the F/M Versions should have a range of about 38nm however this is not the case in DCS. I've tested two scenarios.

 

1st: L-39C with ROE to Weapons Safe and no reaction to threat @~6000ft and 270KTAS

2nd: Tu-95 with same settings as the L-39 but @ 35000ft and 270KTAS

 

During the first test I shot two AIM-7F. One at 15nm and one at 10nm - Both missed due to no energy.

 

The second test I fired the same two AIM-7F but one at MaxPk (~28nm) and one at 20nm. The first one missed also due to no energy but the second hit the 'Bear'.

 

Worth noting is that in those tests I always flew in full burner, during the second test I even reached Mach 1.6. So my conclusion is, that you can in fact hit your target, but only if you give the missile a huge energy boost from the start.

 

I've also provided two tracks, one for each test.

 

Greetings

- K

FA-18 AIM7Bug.trk

FA-18 AIM7Bug2.trk

[jojo]

Missile range without launch parameters worth nothing.

 

First: are we talking about launch range or interception range ?

Launcher speed & altitude, target speed & altitude, target aspect...then we can start to talk.

 

So Wikipedia 38Nm is of little help.

 

Plus your 2 targets are slow movers, and one at 6000ft.

 

So maybe the DCS AIM-7F/M isn't up to its real life specification, maybe the launch zone isn't accurate, but 270KTAS targets won't fill the bill for max range launch.

[Mr_Burns]

It is all EA at the end... they've said that they will work on the missiles, nothing is final. I still haven't fired any in the Hornet, but ....

 

We can start bitching when it is "stable" and it doesn't work

 

 

I dont think we are bitching, I have just watched youtube and set up a -18 vs -25 and in 6 attempts getting all 4 missiles away, I havnt hit it once, not even near.

 

 

So would like to know before I put any more time into trying to kill the thing if it is User Crappiness or Early Access. Either would be good to know as I can still perfect locking the enemy without expecting to hit it!

[HawkDCS]

Well I made a few tracks. One where all 4 missed even at less then 12. I fired every two miles to only have them skew off into random directions. How do I upload a track?

Edited June 3, 2018 by HawkDCS

[antagonist]

AIM-7 intercept behavior

 

Something peculiar happens to the AIM-7 when I fire it at a target crossing my nose at a constant speed and heading.

 

What I assume should happen is the missile's seeker head calculating an intercept point along the target's course, then moving towards it in an almost straight line.

 

What I see happening instead is the missile at first behaving just like this, and then the rocket motor burns out.

Immediately afterwards, it attempts to acquire a different intercept vector due to the sudden and totally unanticipated loss of thrust, and in doing so, losing so much speed it falls out of the sky.

 

Shouldn't the seeker be aware of how much burn time its rocket motor has and calculate the intercept vector accordingly so massive course changes don't become necessary?

 

E: The target in question was beaming me at less than 13 nm, going less than 400 kts. The missile travelled around 15-18 nm before it encountered loss of control due to drag. This is a ballpark figure unless someone would be kind enough to tell me if and where Tacview may store this kind of information.

[jojo]

You need a registered TacView liscence to analyse missile’s range Vs time curve.

[briosky2]

Instant Action Aim 7 Caucasus

 

I think there may be a bug here. Shot a Mig 25 and didn't kill it. Sending screen shot of it.

[Weta43]

I just tried @ 15000m alt, F/A-18 1366 km/h TAS head on against B1B 1500 km/h TAS

Options set to no reaction to threat, by the time I moved the designator & locked I had a launch cue so launched at 47km (26 nm ?), missile hit half a second after the motor burned out.

[antagonist]

I just tried @ 15000m alt, F/A-18 1366 km/h TAS head on against B1B 1500 km/h TAS

Options set to no reaction to threat, by the time I moved the designator & locked I had a launch cue so launched at 47km (26 nm ?), missile hit half a second after the motor burned out.

 

It worked because the missile didn't have to do any sort of corrections to its flight path. Try firing at a target beaming you, where an additional ~10 seconds of flying time would have let the missile hit and see it start to flounder immediately after burnout.

 

https://cdn.discordapp.com/attachments/199290542796963850/453212666937344000/Tacview-20180602-230441-DCS-SoH_FA-18C_AIM-7_Sparrow.zip.acmi

 

I fired from well within the effective range, but outside the NEZ. The target plane never maneuvered to counter the missile and never meaningfully changed speed.

[Chrinik]

I would much rather like to know why we can only carry 4 Sparrows max?

Is this actually the case? I could have sworn the inboard wing pylons can also carry Aim 7s but I can't for the life of me find any pictures, as Hornets seem to be deployed with wingtanks 90% of the the time.

[Dav IRL]

I am hitting with them but they seem a little weak, hmmmm.

[blkspade]

I know that you can in fact hit non-maneuvering targets at 26nm with the AIM-7M in the game with either the F-18 or F-15. You can't even fire beyond that range (Rmax) in the F-18 no matter what the closure rate is. Perhaps that'll change when they implement the lofting logic. also, it does seem as though there is only 1 AIM-7M in game that both jets share. If the target evades you'll certainly miss, mostly due the radar not maintaining lock which may be partially induced by chaff. The absolute best you could hope for against a defending target in the eagle with Aim-7s is about 18nm. 15nm against a human that won't turn cold or beam against your high energy shot. There is a huge problem with the drag considering a 40,000 launch should get as far 53nm before it can no longer manuever, yet only gets about 25nm. Interestingly enough in its current state the AIM-7 has better kinetic performance than the AIM-120B.

[Tango777]

AIM-7 misses

 

The AIM-7 Sparrow misses every time. I get a solid lock on the right TDI's radar page, in the hud the green dot is in the target box, the word "SHOOT" begins to flash, and then I launch the AIM-7. It flies toward the target perfectly and then about 0.5 nm short of the target the AIM-7 turns right, or left, or above, or below the target every time no matter the enemy aircraft type.

 

What am I doing wrong?

[Sierra99]

The best thing to do is fly a mission and produce the results you believe are wrong. In this case the missiles going stupid.

 

Post the trk file of the mission and a short description of what you did to produce the results in the bugs section.

[Tango777]

After the mission do I need to click Save Track and then post that file in the bugs section? Just want to make sure.

[fmedges]

I have maybe a 25% success rate myself.

[DocSigma]

Are you losing your lock on the target? Aim7's are semi-active and are not fire and forget missiles like the Aim120's or R77. You need to maintain your target lock until the missile hits it's mark. One thing I have noticed is that the radar loses lock very easily in the Hornet. It's almost as if you have no maneuvering ability after you fire the Aim7. I don't know if this is how it's supposed to function or a bug in the radar.