DCS: F-14 Development Update - AIM-54 Phoenix Improvements & Overhaul - Guided Discussion

[draconus]

10 hours ago, Naquaii said:

The guidance however is lacking which makes the missile worse off than it should be due to that, but that also not really something a 3rd party can fix.

Do you track it with ED? Is it WIP or just planned for the future?

[Sindar]

-Cipher-   the only one who has written anything in this discussion that makes common sense. This is evidenced by the number of endorsements of his post.

В 15.01.2024 в 20:41, -Cipher- сказал:

it was very very common that lots of Iraq planes jettisoned their bombs as soon as locked by an F-14 (commonly mentioned, mentioned by Shahram Rostami as well)

В 15.01.2024 в 20:41, -Cipher- сказал:

I don't really like the way some people want to represent the phoenix as a slow fat brick only able to crash into straight flying big bombers. 
Phoenix is a very capable missile, and it is proven to be a very good and reliable weapon against agile fighters even in DCS with current state. 

В 15.01.2024 в 20:41, -Cipher- сказал:

these maneuvers did not help them as they got close as below 20 nautical miles, missiles fired within that range had a really good PK and I don't remember reading somewhere they miss within that window,

Why is HB constantly mentioned and justified here? If this rocket is made by Mexicans in a small town car shop, but done well, it makes no difference to me who they are or what their name is. Personally, I have no beef with HB.  The end product is the result of ED's work. And the ED, unfortunately, is silent.

From others I read again a thousand words about everything but the answer to a simple question. What class of missile in the current DCS reality does the AIM-54 belong to?

Long or midle?

 

[draconus]

7 minutes ago, Sindar said:

Long or midle?

Long.

[Naquaii]

11 hours ago, draconus said:

Do you track it with ED? Is it WIP or just planned for the future?

Afaik it's an ongoing thing.

[DD_Fenrir]

AIM-54 has changed again.

In vCVW-17 since the last patch we are seeing a drop in overall Pk to a ~25%  level vs ~45% at the end of last year.

Notch resistance seems to have plummetted plus terminal energy is down. 

This is bloody frustrating. Our BVR timelines are all over the place. 

Can someone please justify these changes and at the very least ensure that patch notes reflect any adjustments to the AIM-54 physics.

[DSplayer]

3 hours ago, DD_Fenrir said:

AIM-54 has changed again.

In vCVW-17 since the last patch we are seeing a drop in overall Pk to a ~25%  level vs ~45% at the end of last year.

Notch resistance seems to have plummetted plus terminal energy is down. 

This is bloody frustrating. Our BVR timelines are all over the place. 

Can someone please justify these changes and at the very least ensure that patch notes reflect any adjustments to the AIM-54 physics.

At least nothing code-wise has changed on the end that I can see. No drag, motor, or guidance changes that I can see. If it were something that changed, it would probably be on ED's end.

[Karon]

I haven't checked this post in a while, and apparently, I missed a lot of nonsense. Skipping the complaints about realism whilst mentioning ""Cybersport"" which cracked me up, there are lots of posts in this infinite thread that talks about the current issues of the missiles, the game in general (inconsistent radar and missile simulation, rwr, bug/exploits and so on - lol at esport again), and the fact that the Phoenix in DCS is actually a good missile no matter the API limitations. It has a very high top speed but slow acceleration; its behaviour changes a lot depending on the range, and whoever expects a preventively defending target to be splattered at 70 nm does not know how the phoenix works. At those ranges, a minor offset or changes in Vc can seriously affect the missile envelope.

 

So far, people complaining mostly have three-four main "issues":

- they haven't tweaked the AI to make it less dumb but exceptional at notching;

- they play with no set era. Who would have thought that missiles from 2000+ are better than the Phoenix, especially vs fighters, right?

- they play against modules with subpar avionics simulation: everyone can defeat a Phoenix if their SA and RWR are better than the F-35's fusion;

- they expect Pk to be 100%. Well, it doesn't work like that.

Obv this does not mean that there no issues, on the contrary, but the game can be made better and closer to real situations. It's boring AF, but only a matter of patience and will.

 

Sorry to sound a bit annoyed, but I can't believe that almost 60 pages later we are still repeating the same things.

Edited March 27, 2024 by Karon
typos - I have cellular phones

[DD_Fenrir]

3 hours ago, Karon said:

I haven't checked this post in a while, and apparently, I missed a lot of nonsense. Skipping the complaints about realism whilst mentioning ""Cybersport"" which cracked me up, there are lots of posts in this infinite thread that talks about the current issues of the missiles, the game in general (inconsistent radar and missile simulation, rwr, bug/exploits and so on - lol at esport again), and the fact that the Phoenix in DCS is actually a good missile no matter the API limitations. It has a very high top speed but slow acceleration; its behaviour changes a lot depending on the range, and whoever expects a preventively defending target to be splattered at 70 nm does not know how the phoenix works. At those ranges, a minor offset or changes in Vc can seriously affect the missile envelope.

 

So far, people complaining mostly have three-four main "issues":

- they haven't tweaked the AI to make it less dumb but exceptional at notching;

- they play with no set era. Who would have thought that missiles from 2000+ are better than the Phoenix, especially vs fighters, right?

- they play against modules with subpar avionics simulation: everyone can defeat a Phoenix if their SA and RWR are better than the F-35's fusion;

- they expect Pk to be 100%. Well, it doesn't work like that.

Obv this does not mean that there no issues, on the contrary, but the game can be made better and closer to real situations. It's boring AF, but only a matter of patience and will.

 

Sorry to sound a bit annoyed, but I can't believe that almost 60 pages later we are still repeating the same things.

 

Karon, with the greatest respect, I have been a proponent of "Phoenix = not a golden BB" philospohy myself for some time.

That said given that our mil-sim air wing operates the AIM-54 on - as close as we can gather to - actual AIM-54 timelines, that is, >30Kft, 0.9-1.0M, hot targets, 20°-30° manual loft launching at between 50nm and 35nm.

Without changing an iota of how we operate, the Pk is dropping - we track or weapons envelope employments to gather robust data on this and it is showing a downward trend.

We could stand a PK of around 40-45%. That's reasonable; the enemy gets a vote after all and sometimes the AWG-9 does AWG-9 things. But something HAS changed, and the Pk overall is dropping.

Repeatedly our missiles are getting trashed in the endgame - whilst still kinematically viable -  because *reasons*; two of us launched a total of 8 Phoenixes at a Backfire raid that was climbing through 20Kft at 45nm (still launching ~32K @ 0.9M with manual loft) the other day.

ONE hit.

ONE.

One went stupid after a track file loss (fair enough) and the other 6 were all somehow notched and passed within 100ft of their target. By BACKFIRES. This is not a hard manoevering target but a large bomber that doesn't manouvre well.

It is ridiculous, on that we agree, I just think it's ridiculous that the missile still performs so badly even when launched under optimal conditions. 

Edited March 27, 2024 by DD_Fenrir

[draconus]

22 minutes ago, DD_Fenrir said:

Repeatedly our missiles are getting trashed in the endgame - whilst still kinematically viable -  because *reasons*

https://forum.dcs.world/forum/535-bugs-and-problems/

[Karon]

1 hour ago, DD_Fenrir said:

Karon, with the greatest respect, I have been a proponent of "Phoenix = not a golden BB" philospohy myself for some time.

That said given that our mil-sim air wing operates the AIM-54 on - as close as we can gather to - actual AIM-54 timelines, that is, >30Kft, 0.9-1.0M, hot targets, 20°-30° manual loft launching at between 50nm and 35nm.

Without changing an iota of how we operate, the Pk is dropping - we track or weapons envelope employments to gather robust data on this and it is showing a downward trend.

We could stand a PK of around 40-45%. That's reasonable; the enemy gets a vote after all and sometimes the AWG-9 does AWG-9 things. But something HAS changed, and the Pk overall is dropping.

Repeatedly our missiles are getting trashed in the endgame - whilst still kinematically viable -  because *reasons*; two of us launched a total of 8 Phoenixes at a Backfire raid that was climbing through 20Kft at 45nm (still launching ~32K @ 0.9M with manual loft) the other day.

ONE hit.

ONE.

One went stupid after a track file loss (fair enough) and the other 6 were all somehow notched and passed within 100ft of their target. By BACKFIRES. This is not a hard manoevering target but a large bomber that doesn't manouvre well.

It is ridiculous, on that we agree, I just think it's ridiculous that the missile still performs so badly even when launched under optimal conditions. 

 

Sorry mate, I was not talking about you; I should have specified. I was referring to the broader discussion. This, assuming it is not a one-off occurrence, seems to be the side effect of something changed on ED's side since they control terminal guidance, and I am not aware of any changes on HB's side. Do you have tracks / tacview, or have new noticed if there was something in common between the shots? Laggy server otherwise? Finding a common point and recreating the problem would help to find the solution.
I'm happy to test the same conditions (SP though) if you provide more details.

[Lurker]

@Karon ED might very well be unaware of the problem, if this is an unintended consequence (read > bug) of some other changes they made. You have an ED Closed Beta Tester Team tag, so you probably know best how this works and how many new bugs are introduced for every one they squash.

[WarthogOsl]

I know there weren't any HB updates this last patch (April 10), but does anyone know of any ED changes to radar or guidance?  I've been seeing some consistently wonky behavior with the Phoenix since then. In this example (on a single player mission I've often used for practice), the second missile loses track almost immediately after launch, and makes a bee-line into the stratosphere.  A third, follow up shot taken while still about 55 miles away barely lofts at all.  It seems like most of the time since the patch, the second missile fired at a 2 ship won't even make it even near the target, let alone any terminal problems.

[The_Tau]

yeah i think there is something linked with firing on close flying two-ships. I just had the same during my squadron mission. 1 missile goes to space, another one tracks nicely

 

https://we.tl/t-6Gn8GdLhWm

 

at +01:25:39

Edited April 15, 2024 by The_Tau

[WarthogOsl]

7 minutes ago, The_Tau said:

yeah i think there is something linked with firing on close flying two-ships. I just had the same during my squadron mission. 1 missile goes to space, another one tracks nicely

 

I remember it being more of an issue a long while ago, but fixed for the most part.  There are definitely times where I see the track of the trailing bandit pop in and out, while the lead stays solid.  In those cases I will hold off on firing two missiles.  But in these cases it seemed I had a solid track and both, right up until launching #2.

[Kageseigi]

14 hours ago, WarthogOsl said:

I know there weren't any HB updates this last patch (April 10), but does anyone know of any ED changes to radar or guidance?  I've been seeing some consistently wonky behavior with the Phoenix since then. In this example (on a single player mission I've often used for practice), the second missile loses track almost immediately after launch, and makes a bee-line into the stratosphere.  A third, follow up shot taken while still about 55 miles away barely lofts at all.  It seems like most of the time since the patch, the second missile fired at a 2 ship won't even make it even near the target, let alone any terminal problems.

 

In light of recent events, the cynic in me says your problem in this particular case is because the MiG-23 is already dead 

[WarthogOsl]

1 hour ago, Kageseigi said:

 

In light of recent events, the cynic in me says your problem in this particular case is because the MiG-23 is already dead 

Lol.  I get what you're saying, though fwiw just in case, I tried it with some MiG-25's as well.  Same thing :)

[trenchfeet]

I agreed two close bandits is one missile in space and another losing guidance due to the other popping in and out

[riboyster]

Not sure if this has already been discussed/address - please fill me in if so.

When firing a phoenix at 40k feet from mach 0.9, the missile barely makes it past Mach 2. Public data has it as a Mach 4 missile. What gives?

[NeedzWD40]

40 minutes ago, riboyster said:

Not sure if this has already been discussed/address - please fill me in if so.

When firing a phoenix at 40k feet from mach 0.9, the missile barely makes it past Mach 2. Public data has it as a Mach 4 missile. What gives?

Mine are making it past Mach 3 depending on the loft altitude. Lower altitudes without a loft is usually a Mach 2.5 cap. The Mach 4 figures are from a NASA testbed missile. It's been discussed in this thread before, but I've no idea what page it's on.

[riboyster]

1 hour ago, NeedzWD40 said:

Mine are making it past Mach 3 depending on the loft altitude. Lower altitudes without a loft is usually a Mach 2.5 cap. The Mach 4 figures are from a NASA testbed missile. It's been discussed in this thread before, but I've no idea what page it's on.

Got it. Thanks!

[draconus]

On 4/27/2024 at 5:47 AM, NeedzWD40 said:

The Mach 4 figures are from a NASA testbed missile. It's been discussed in this thread before, but I've no idea what page it's on.

[tavarish palkovnik]

Hmm, much more documents talk about velocity above 4M.

Luckily professor Tsiolkovsky left us theorem which still holds undisputed  -> v=Isp*ln(m0/m1)

One documented sample, rocket R-40 (MiG-25) of similar exterior and drag respectively. It says maximal velocity missile itself generates depending on altitude and launch speed is 540 to 720m/s. Of course lower level of stratosphere (above tropopause) should be considered as altitude for maximal, and there speed of sound is 295m/s what will be needed to convert it to Mach number.

R-40 is with starting weight of 470kg, propellant weight is 118kg…ln(470/352)*Isp=720 … Isp=2490 Ns/kg

This is specific impulse up there after real one is degraded by drag loses.

Motor of R-40 works on much higher pressure then one of AIM-54, pressure increases specific impulse, but motor of AIM-54 has high expansion ratio of nozzle which also increases impulse on altitude and turn it and twist it all around…that could be like deuce in tennis.

 

 

Why not to consider same specific impulse for AIM-54 … ->
ln(447/279)*2490=1174m/s … -> 1174/295=3,98 M … maximal self generated velocity of missile.

Information on internet often can be quite vague

Edited April 29, 2024 by tavarish palkovnik

[RustBelt]

As with all documents of Soviet equipment, has it been independently verified? There was, and is, a lot of “politically approved” science being done.

[The_Doktor]

Thank you very much Tavarish Palkovnik

so in theory, at see level without drag the missile could go nearly as fast as Mach 4 if the both are comparable?

THX agin

2 hours ago, tavarish palkovnik said:

Hmm, much more documents talk about velocity above 4M.

Luckily professor Tsiolkovsky left us theorem which still holds undisputed  -> v=Isp*ln(m0/m1)

One documented sample, rocket R-40 (MiG-25) of similar exterior and drag respectively. It says maximal velocity missile itself generates depending on altitude and launch speed is 540 to 720m/s. Of course lower level of stratosphere (above tropopause) should be considered as altitude for maximal, and there speed of sound is 295m/s what will be needed to convert it to Mach number.

R-40 is with starting weight of 470kg, propellant weight is 118kg…ln(470/352)*Isp=720 … Isp=2490 Ns/kg

This is specific impulse up there after real one is degraded by drag loses.

Motor of R-40 works on much higher pressure then one of AIM-54, pressure increases specific impulse, but motor of AIM-54 has high expansion ratio of nozzle which also increases impulse on altitude and turn it and twist it all around…that could be like deuce in tennis.

 

 

Why not to consider same specific impulse for AIM-54 … ->
ln(447/279)*2490=1174m/s … -> 1174/295=3,98 M … maximal self generated velocity of missile.

Information on internet often can be quite vague

 

 

[tavarish palkovnik]

10 hours ago, The_Doktor said:

so in theory, at see level without drag the missile could go nearly as fast as Mach 4 if the both are comparable?

 

No it wouldn't because specific impulse is very fluid value. In such hypothetical (impossible) case where atmosphere influence by chocking motor but in same time does not produce drag, missile would reach maximum 3 M

Take a look page in front, those diagrams how specific impulse change with chamber pressure, nozzle expansion ratio and altitude. Phoenix motor is with nozzle ratio 18,5 and average pressure is 700psi so easily case with nozzle ratio 20 and pressure 750psi can be used. Down there specific impulse is 220s (I've got 216s in calculation) ->

 

 

  

 

 

So down there impulse should not be 2490 Ns/kg but 2158 Ns/kg (220*9,81) and together with ln(447/279) it makes 1017m/s or 3M (speed of sound at sea level is 340,28m/s)

Of course this combination without drag at sea level is just empty talks, but up there where atmosphere is rear, where this awkward motor gives high impulse (range of 270-275s) things are significantly different