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

[Machalot]

On 4/29/2024 at 11:30 PM, tavarish palkovnik said:

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

If I remember correctly, the nozzle exit area was not modeled for the AIM-54 in DCS, so altitude doesn't affect the thrust. 

[tavarish palkovnik]

23 hours ago, Machalot said:

the nozzle exit area was not modeled for the AIM-54 in DCS, so altitude doesn't affect the thrust. 

It hasn’t been “independently verified” so it doesn’t count 

 

 

[Harlikwin]

4 hours ago, tavarish palkovnik said:

It hasn’t been “independently verified” so it doesn’t count 

 

 

I mean how you not have the nozzle exit area not modeled and altitude not effect thrust? Holy cow.

 

[RustBelt]

3 hours ago, Harlikwin said:

I mean how you not have the nozzle exit area not modeled and altitude not effect thrust? Holy cow.

 

I mean, deep down, this is still a Pentium III and sub 1GB RAM level game in its physics bones. It’s not even a spherical earth model, so don’t expect the most sophisticated Stratosphere (Stratobox?) simulation. 

[Harlikwin]

10 minutes ago, RustBelt said:

I mean, deep down, this is still a Pentium III and sub 1GB RAM level game in its physics bones. It’s not even a spherical earth model, so don’t expect the most sophisticated Stratosphere (Stratobox?) simulation. 

Lets not talk about things like an IR model, or you know Ray-dar

[Machalot]

4 hours ago, Harlikwin said:

I mean how you not have the nozzle exit area not modeled and altitude not effect thrust? Holy cow.

 

It's not that DCS doesn't have such a model.  The particular parameters for the AIM-54 were set to use thrust adjusted to at a specific altitude and zero nozzle exit area, which effectively disables the effect of different altitudes on thrust. 

Edited May 3, 2024 by Machalot

[captain_dalan]

11 hours ago, Machalot said:

It's not that DCS doesn't have such a model.  The particular parameters for the AIM-54 were set to use thrust adjusted to at a specific altitude and zero nozzle exit area, which effectively disables the effect of different altitudes on thrust. 

 

I know ED have their hands full, and HB too, but why not let the community make the modifications and submit the solution and the calculations for review, and then include those into the code base? I'm sure many among us would do this free of charge, even in times such as these. when many of us struggle to make ends meet or keep their jobs. 

[Machalot]

5 hours ago, captain_dalan said:

I know ED have their hands full, and HB too, but why not let the community make the modifications and submit the solution and the calculations for review, and then include those into the code base? I'm sure many among us would do this free of charge, even in times such as these. when many of us struggle to make ends meet or keep their jobs. 

I can't speak for anybody but myself.  But there's a nontrivial amount of work required to incorporate code or script changes, even moreso when they are provided by a third party.  Software QA, testing, repo maintenance, etc.  I can only speculate they don't have the resources to spare, and this is one more little thing that is not a high priority compared to, say, shipping the F-4.

[RustBelt]

9 hours ago, captain_dalan said:

I know ED have their hands full, and HB too, but why not let the community make the modifications and submit the solution and the calculations for review, and then include those into the code base? I'm sure many among us would do this free of charge, even in times such as these. when many of us struggle to make ends meet or keep their jobs. 

Because DCS is the free spinoff of a paid training product. ED believes they have industrial secrets deserving of protection. It’s not old abandonware that got its source code dumped by some packrat dev. It’s a going concern that just happens to also have a “free” branch. After people got in the old version to keep running the hawk, ED has locked down the code pretty tight. Just ask any unofficial mod maker how hard it is to do things like integrate radios. 

[draconus]

On 5/3/2024 at 5:00 PM, captain_dalan said:

why not let the community make the modifications

That's just not how it works. It's their code. If it's wrong make a proper bug report, say how it should be and that's it. Your job is done here. They'll review it and act accordingly.

[tavarish palkovnik]

Tomorrow or in coming days I will share you complete calculations about this motor, it is actually already done after some time of investigation, base is done and I will just add some finesses like erosion of throat and temperature sensitivity coefficients to see how it works at min and max temperature.

No wish whatsoever to implement it in this game, just want to write something what is different to what circulates on the internet about this motor (motors) … just want to make it correct

[captain_dalan]

12 hours ago, draconus said:

That's just not how it works. It's their code. If it's wrong make a proper bug report, say how it should be and that's it. Your job is done here. They'll review it and act accordingly.

It's quite obvious that it's not how it works, i'm just suggesting things might be different if enough good will exists on both sides.

On 5/3/2024 at 10:42 PM, Machalot said:

I can't speak for anybody but myself.  But there's a nontrivial amount of work required to incorporate code or script changes, even moreso when they are provided by a third party.  Software QA, testing, repo maintenance, etc.  I can only speculate they don't have the resources to spare, and this is one more little thing that is not a high priority compared to, say, shipping the F-4.

For some of it yes, but other things, like basic weapon parameters, say motor thrust or nozzle area in this case, it's not really all that hard to change and test the changes. And after the changes are being made by the community, you just need to let your QA team test them and confirm or not the end result. 

[Machalot]

44 minutes ago, captain_dalan said:

For some of it yes, but other things, like basic weapon parameters, say motor thrust or nozzle area in this case, it's not really all that hard to change and test the changes. And after the changes are being made by the community, you just need to let your QA team test them and confirm or not the end result. 

But who says the QA team has any spare time to test something like this when they're also incorporating massive changes to the F-4 on a tight cycle?  Maybe working 10-12 hour days already, weekends, who knows.  Accepting changes from a third party requires a lot of testing to ensure nothing else gets changed for the worse.  We know from experience that changes to "only" basic weapon parameters can result in 58-page forum threads, full of complaints and debates, that still get new posts 18 months later.

Again I'm only speaking based on my own experience writing software professionally, not on anyone's behalf.

Edited May 5, 2024 by Machalot
can't do math

[draconus]

7 hours ago, captain_dalan said:

For some of it yes, but other things, like basic weapon parameters, say motor thrust or nozzle area in this case, it's not really all that hard to change and test the changes.

It might work for small group of enthusiasts or modders but not when business is involved when even preparing the changes, tests and files for community takes additional time then changes and results need to be looked upon, understood and tested again. Sometimes it is done though in special cases to test in larger groups or beta programs.

But why Phoenix needs any changes now? Where's the bug report?

[captain_dalan]

1 hour ago, draconus said:

 

But why Phoenix needs any changes now? Where's the bug report?

We who work in software development, don't make changes just because there are bugs in our code, sometimes we make them in order to introduce new features.

8 hours ago, Machalot said:

But who says the QA team has any spare time to test something like this when they're also incorporating massive changes to the F-4 on a tight cycle?  Maybe working 10-12 hour days already, weekends, who knows.  Accepting changes from a third party requires a lot of testing to ensure nothing else gets changed for the worse.  We know from experience that changes to "only" basic weapon parameters can result in 58-page forum threads, full of complaints and debates, that still get new posts 18 months later.

Again I'm only speaking based on my own experience writing software professionally, not on anyone's behalf.

 

True. But it certainly would take less man hours then having your teams do ALL the work. 

[tavarish palkovnik]

As promissed, here it is 

 

pk AIM-54.pdf

 

It is free to use, if you once decide to make modification OK, if not again OK, I do not play this game after all so it will not bother me. But what bothers me is that most of googling about this motor is related to DSC and WT, and data coming from there, data which are simply wrong. Tomorrow when and if AI takes control, hopefully never, it will be spectacular.

It is an order to share it here, after all, here in all these pages huge portion is done, geometrical features of motor and concept and geometry of grain raised up, and that made half of work done. Rest is just merging of it with existing and available output data about this motor, by using common theory about rocket propulsion with various data related to that time, and here it is.

For any question about any of these steps, data, formulas, whatever, I'm available 

[Aekay]

Very cool and very well detailed! And the best: ALL of this is DECLASSIFIED information!!

5 hours ago, draconus said:

But why Phoenix

Is this guy a (joke) comedian, or does he just like to close his eyes to reality to maintain ED's 4s5-kissing attitude around here?

[Xhonas]

This is definitely interesting, but i doubt Heatblur will accept science like this. Just the other day, an aerospacial engineer showed up on their discord and proved to them that the F14 flaps don't have induced drag modelled (this generates an unrealistic boost in slow speed dogfighting performance) and Heatblur received him with cynicism, sarcasm and straight up rejected his finds. Heatblur believes that they are the best dev's in DCS and that they can never be wrong. Those guys have a huge ego. Disappointing. 

Edited May 5, 2024 by Xhonas

[Aekay]

4 minutes ago, Xhonas said:

Disappointing.

Well said bro. This is the word that exactly fits this whole story.

 

[Katsu]

58 minutes ago, tavarish palkovnik said:

As promissed, here it is 

 

pk AIM-54.pdf 3.09 MB · 2 downloads

 

It is free to use, if you once decide to make modification OK, if not again OK, I do not play this game after all so it will not bother me. But what bothers me is that most of googling about this motor is related to DSC and WT, and data coming from there, data which are simply wrong. Tomorrow when and if AI takes control, hopefully never, it will be spectacular.

It is an order to share it here, after all, here in all these pages huge portion is done, geometrical features of motor and concept and geometry of grain raised up, and that made half of work done. Rest is just merging of it with existing and available output data about this motor, by using common theory about rocket propulsion with various data related to that time, and here it is.

For any question about any of these steps, data, formulas, whatever, I'm available 

This information should at least be reviewed by the team, and if it is rejected, at least a reason should be given for it. There is a lack of transparency in the development process when it comes to Phoenix, so far we have a missile made up of speculation.

 

What i find most strange is that compared to the public data, the Phoenix is the only missile in the game that, in order to reach the published speed, requires launch parameters that the launcher plane can't reach, using the 120C as an example, where we can even go beyond the public data published about it.  (Not asking the same for phoenix, but If you get the sucess rate reports from tests and game you will see a HUGE discrepancy in the fact that the weapon is barely can simply do what it was designed to do with the hit rate of a Phoenix C being even lower than that of the Phoenix A tests..)

I Hope that the state of this missile is atleast reviewed and explained at some point. 

Not Just "according our sources" what sources? Where is the math for this?

I think that we have a solid paper here to help with this.

And even if nothing is done, I think Tavarish deserves a thank you for trying to bring a little transparency and information at least in theory as things should be.

Edited May 5, 2024 by Katsu

[Harlikwin]

Ehh, if we are looking for problems with the F14, the radar could certainly need a 2nd look so it can't be abused into the eye of Sauron  by backseaters, and maybe just maybe stop tracking parked planes.

 

 

[Aekay]

2 hours ago, Harlikwin said:

stop tracking parked planes

Be Welcome to  the Pulse Search Single Target Track Without Doppler Filter.

[Harlikwin]

2 hours ago, Aekay said:

Be Welcome to  the Pulse Search Single Target Track Without Doppler Filter.

Yeah I know. HB "perfection" 101.

[draconus]

On 5/5/2024 at 1:21 PM, draconus said:

But why Phoenix needs any changes now? Where's the bug report?

Now this is a good expample. Phoenixes going straight into space after loosing the TWS track is not realistic behavior.

[RustBelt]

And it’s an ED problem so…..yea…