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

[tavarish palkovnik]

Motor or motors  because there are plenty of those.

Mk38 Mod.0,1,2

Mk38 Mod.3,4

Mk52 Mod.1,2

Mk65

Mk58

 

First three groups are with similar (nearly same) output and different and/or nearly same concept.

Last two motors are with similar/same output but completely different concept.

These last two are interesting because numbers circulating behind it on the Internet are just like in case of Phoenix very tricky

 

[GGTharos]

Yep, the last two are what I would be interested in

[tavarish palkovnik]

There will be plenty of work because just like in case of Phoneix motor, Internet is, for these motors as well, full of contradictions

This specification here is example, simply these numbers are in mess

 

 

There are pressure rates, there is nozzle geometry, all what is needed to define thrust in the most precise way. 

Boost 1769 psi (122 bar) ; sustain 301psi (20,7 bar). These number seems as reasonable and correct. Mk58 is motor of really complicated concept and it is not easy to make some calculations without having exact data for propellants. This what is written in table above is not enough, 12,7mm/s at 69bar (1000psi) is obviously for booster grain, at 122bar it would be with 0,3 burn rate pressure exponent 15mm/s and geometry follows it well, 4,5 seconds x 15mm/s = 67,5mm what is web of booster grain actually. But for sustain grain we have nothing. By the way, this burning time is strange and I think result of ''tuning'', I would rather stay at 4,5/11 seconds as stated in well known document about AIM-7F. 

Mk65 is for me of much more convenient design 

 

 

Unfortunately there is no cross cut view in full length so we don't know exact length ratio between cylinder and slots, but for example in this length ratio and for 4,5/11 seconds burning time, pressure ratio 122/21 bar with same nozzle geomery is achievable without any problems. Both motors, Mk58 and Mk65 should have same or very similar output of course.

So if we take pressure data as correct, we have nozzle expansion ratio as 6,2 and let's say heat ratio is 1,2 (very sure it is, most of US propellants of that time is with such ratio)

 

 

Thrust coefficient is boost is 1,63 and in sustain 1,37, nozzle throat diameter is 38,5mm. Now all what is needed to calculate thrust at sea level is here. There is also info that half angle at nozzle exit is 15deg so thrust loss can 0,98 -> (1+cos15)/2

Boost -> 0,98*1,63*12,2 (MPa) * 1163,56 (mm2)=22675 N or 5097 lbf

Sustain -> 0,98*1,37*2,07*1163,56=3234 N or 727 lbf

Not even close. What about thrust at 20000ft (6000m). Over there thrust coefficients are 1,65 and 1,53 so thrust would be 22955 N/3611 N or 5160 lbf/812 lbf ... still nothing close but those are real numbers if pressure rate is correct.

This is for start...there is still lot to say about this 

[Sindar]

54 pages of discussion and explanation. And the real picture online now is as follows: 1-2 F-14 players for the whole team of thirty pilots. A year ago it was 6-8 players per team. You can draw 54 more pages of charts, but it won't change the fact that F-14s are toothless junk now. That's why it's 40% off. He's unplayable online. That's a fact. It used to be the most dangerous enemy of all. And nobody's gonna change that. The developer gave all the answers half a year ago. Just suck it up and calm down. Nobody reads you anymore.

Edited December 2, 2023 by Sindar

[draconus]

On 12/1/2023 at 2:40 PM, tavarish palkovnik said:

nozzle throat diameter is 38,5mm

In the doc above it's 3.78in.

[tavarish palkovnik]

It says nozzle exit diameter is 3,78 inches (96mm)

Also that throat area is 1,81 sq.inches so throat diameter is 1,518” (38,56mm)

96^2/38,56^2=6,2 what is nozzle expansion ratio

Today I was doing lot of “mental gymnastics” about all these numbers, not sure but perhaps I managed to make some basis for Mk58 relatively to presented numbers. In coming days  I will show it, perhaps even tomorrow if everything fits.

 

[Frosty2124]

1 hour ago, Sindar said:

That's why it's 40% off. 

 

 

 That's not how that works chief . the discount is to encourage sales, not due to the fact that its "poor" this isn't a balanced game....or a used car dealership.

Edited December 2, 2023 by Frosty2124

[DD_Fenrir]

2 hours ago, Sindar said:

54 pages of discussion and explanation. And the real picture online now is as follows: 1-2 F-14 players for the whole team of thirty pilots. A year ago it was 6-8 players per team. You can draw 54 more pages of charts, but it won't change the fact that F-14s are toothless junk now. That's why it's 40% off. He's unplayable online. That's a fact. It used to be the most dangerous enemy of all. And nobody's gonna change that. The developer gave all the answers half a year ago. Just suck it up and calm down. Nobody reads you anymore.

 

https://giphy.com/gifs/vidiots-official-H62aA8TKX9GPSWPLk9

[Sindar]

3 hours ago, Frosty2124 said:

That's not how that works chief . the discount is to encourage sales, not due to the fact that its "poor" this isn't a balanced game....or a used car dealership.

That's right. Incentivize the sale of goods no one wants so they don't take up shelf space. It is not necessary to incentivize the sale of good goods. It will always be bought. And there will always be a shortage of it. It's called high demand. There's no demand for F-14s.

 

P.S. 30% off. My mistake.

[NeedzWD40]

4 hours ago, Sindar said:

You can draw 54 more pages of charts, but it won't change the fact that F-14s are toothless junk now.

I'd be curious to know how you've drawn that conclusion. I was never that big on the 14 to begin with (nor the air combat mission itself), but it's been an interesting module to use. In the ultra-modern era, it's going to have limitations and that's just a fact of life. Like the SA-5 is an old system that can be defeated in certain ways and methods, but you still have to do something when one of those freight trains comes hauling butt at mach "get rekt" and altitude "eye of sauron" at you. So too for the AIM-54, because you can do certain easy things to defeat it, but the mere fact that you have to react to it can make all the difference in the world.

Lately, in the ultra-modern space, I've just been using it to pick off high value targets. Being able to reach out and touch enemy fuelers and AWACS at 80nmi+ is quite a capability. My furthest was an A-50 at 94nmi. And unlike AIM-120 hits, an AIM-54 will knock them down. If I'm not doing that, then I'm using the long legs to deliver precision ordnance on target. The platform itself was built for a particular era, within particular limitations. The mere fact that it can be merely viable in the modern space is amazing in itself, considering that it's predominantly 1960s tech.

I bet if you walked the clock back to 1986-1990 prior to the AIM-120 and R-27ET/ER, you'd find a ton of people just hopping into F-14s with AIM-54 doomsday loadouts. That's just the stupid meta bovine excrement that characterizes DCS multiplayer. Players want to win, and they'll pick whatever is best to do that for the situation. For me, I want to do something interesting and see what happens. How can I knock down that modern advanced fighter with a cold war rust bucket, not how I can't do it.

[Frosty2124]

1 hour ago, Sindar said:

That's right. Incentivize the sale of goods no one wants so they don't take up shelf space. It is not necessary to incentivize the sale of good goods. It will always be bought. And there will always be a shortage of it. It's called high demand. There's no demand for F-14s.

 

P.S. 30% off. My mistake.

Why so salty ? There's nothing wrong with the cat, she's an old girl which more modern designs have taken lessons from and improved upon. 
It's the most faithful representation of an aircraft we have currently in DCS, and shes a challenge to fly.

Just  because you don't like something doesn't mean that it is automatically bad . based on the data and SME opinion it flies like it should, and when someone finds new data that highlights an inconsistency, HB change and update it. it'll never be perfect but all the constructive critiquing helps to get it ever closer

I'll also pick up all the toys and put them back in the pram for you  

Edited December 2, 2023 by Frosty2124

[falcon_120]

54 pages of discussion and explanation. And the real picture online now is as follows: 1-2 F-14 players for the whole team of thirty pilots. A year ago it was 6-8 players per team. You can draw 54 more pages of charts, but it won't change the fact that F-14s are toothless junk now. That's why it's 40% off. He's unplayable online. That's a fact. It used to be the most dangerous enemy of all. And nobody's gonna change that. The developer gave all the answers half a year ago. Just suck it up and calm down. Nobody reads you anymore.

but what's you point Sindar?

You want something "balanced" for competitive MP, or you want a simulation of the real thing? or none...:/

Enviado desde mi ELE-L29 mediante Tapatalk

[tavarish palkovnik]

On 12/1/2023 at 7:41 AM, GGTharos said:

Yep, the last two are what I would be interested in

After quite number of working hours I have something to show regarding these motors, Mk58 actually

 

 

This is concept, of course familar to all, it has two grains with different burning rates. It is not easy to calculate such concept, in way of making program to do all the math when propellants are not same. I guess booster grain is a little bit denser, but to make it more convinient I used same density for both grains and for this geometry it should be 1,75 kg/dm3 to have total of 61,5 kg. Further more, burn rate pressure exponent...for booster grain it is irrelevant because this grain will burn only in one regime, but for sustaine grain this exponent is crucial. If sustaine grain will be with pressure exponent 0,3 than all what is subject to match will fall in water. Sustaine fuel recipe with exponent 0,3 to have faster burning will lead us to pressure way above of targeting 20 bar, 30bar+. It is always a*p^n where ''n'' is exponent in burning law and with ''a'' burning rate can be adjusted (of course in level of feasibility)

I used 0,77*p^0,45 for sustaine grain and 1,89*p^0,45 for booster grain, ''p'' in bars 

Slower burning sustain grain with exponent 0,3 will not be much useful in booster stage and also it would extend burning time way over 20 seconds in total.

Anyway...this is how this should burn, isochores of burning surfaces

 

 

  

And this is what I get ->

 

 

 

It is someting about total time of 16,5 seconds with 4,3 seconds of booster and 12,2 seconds of sutaining mode. Average chamber pressures 124/22,3 bar (1798/323 psi) average thrust 22900/3515 N (5148/790 lbf).

This is fuel consumption, about 40kg (88,19 lbs) in booster and 21,5 (47,4 lbs) in sustain

 

 

 

Why it is not 5750/1018 lbf !?

 

 

 

Americans have some strange and awkward method when presenting these thurst numbers, and when ever chamber pressure is close to 1000 psi (69 bar) and when ever full expansion through the nozzle from that pressure is close to atmospheric pressure of 14,7 psi (1,013 bar) it is OK, but when something other is case, like here, presented numbers are not real or true numbers.

Just shortly on this sample...

Isps could be 250s, standard 69:1 specific impulse. Cfstd is standard thrust coefficient for 69:1 and for k=1,2 and with nozzle expansion ratio 6,2 it is 1,584 

Cftest...this should be thrust coefficient for real chamber pressure and for full expansion.

Booster...it is chamber pressure 124 bar, full expansion will be achieved at sea level (1,013 bar) and thrust coefficent is 1,624 so total thurst will is 250(s) * 9,81 * 1,624/1,584 * 40(kg)=100577Ns and with 4,3 seconds thurst in converted style 23390N (5259lbf)

Sustainer...it is chamber pressure 22,3 bar, full expansion through nozzle with ratio 6,2 will be achieved if ambient pressure is 0,53 bar (atmospheric pressure between 5 and 6 km) and thrust coefficent there is 1,527 so total thurst will is 250(s) * 9,81 * 1,527/1,584 * 21,5(kg)=50831Ns and with 12,2 seconds thurst in converted style 4166N (937lbf)

 

So 5259/937 lbf is closer to 5750/1018 lbf than 5148/790 lbf

 

If numbers 122/20,7 bar ; 3,69/10,86 sec ; 38,46/21,86 kg will be used than it as follows:

250(s) * 9,81 * 1,623/1,584 * 38,46=96646 (Ns) / 3,69 (s) = 26191 N (5888 lbf)

 250(s) * 9,81 * 1,528/1,584 * 21,86=51716 (Ns) / 10,86 (s) = 4762 N (1071 lbf)

 

It is not easy, it is quite complex but for sure I know Mk58 does not gives 5750/1018 lbf as true force

 

 

[Harlikwin]

On 12/2/2023 at 8:29 AM, Sindar said:

54 pages of discussion and explanation. And the real picture online now is as follows: 1-2 F-14 players for the whole team of thirty pilots. A year ago it was 6-8 players per team. You can draw 54 more pages of charts, but it won't change the fact that F-14s are toothless junk now. That's why it's 40% off. He's unplayable online. That's a fact. It used to be the most dangerous enemy of all. And nobody's gonna change that. The developer gave all the answers half a year ago. Just suck it up and calm down. Nobody reads you anymore.

 

LOL literally no one cares. The DCS MP, "need muh bestest jet or uber missile" mindset sucks frankly. The phoenix has been and continues to improve and be more realistic, which is what matters. And frankly the Cat is quite dangerous on most period apropos 70s/80's servers if its flown by a competent pilot at least. But you are right the days of the "I win button" are over and that probably makes some people sad.

On 12/3/2023 at 1:58 AM, falcon_120 said:

but what's you point Sindar?

You want something "balanced" for competitive MP, or you want a simulation of the real thing? or none...:/

Enviado desde mi ELE-L29 mediante Tapatalk
 

The easy "I win button" got taken away. Some people can't cope with that.

[RustBelt]

On 12/2/2023 at 10:29 AM, Sindar said:

54 pages of discussion and explanation. And the real picture online now is as follows: 1-2 F-14 players for the whole team of thirty pilots. A year ago it was 6-8 players per team. You can draw 54 more pages of charts, but it won't change the fact that F-14s are toothless junk now. That's why it's 40% off. He's unplayable online. That's a fact. It used to be the most dangerous enemy of all. And nobody's gonna change that. The developer gave all the answers half a year ago. Just suck it up and calm down. Nobody reads you anymore.

 

You fly a 14 to fly a 14. Who cares about its qualities as an eSports toy? You wanna eSports, you don’t want or care about the 14. 

On 12/2/2023 at 3:07 PM, Sindar said:

That's right. Incentivize the sale of goods no one wants so they don't take up shelf space. It is not necessary to incentivize the sale of good goods. It will always be bought. And there will always be a shortage of it. It's called high demand. There's no demand for F-14s.

 

P.S. 30% off. My mistake.

You don’t have shelves with digital goods. When it earns enough back, you can lower prices to allow more market access. Either through buyers who can’t spend $60+ on a toy, or ones who just never buy at full price. Digital goods work really different.

Edited December 5, 2023 by RustBelt

[tavarish palkovnik]

From -> 

 

It is 5096/807 lbf vs mine 5148/790 lbf

[Machalot]

1 hour ago, tavarish palkovnik said:

It is 5096/807 lbf vs mine 5148/790 lbf

You think this source refers to the Phoenix? 

[tavarish palkovnik]

No…it is now about AIM-7F and it’s motor Mk58 only I don’t know where to write about it  … sorry, I know this is not place for it.

[Sindar]

22 hours ago, Harlikwin said:

LOL literally no one cares. The DCS MP, "need muh bestest jet or uber missile" mindset sucks frankly. The phoenix has been and continues to improve and be more realistic, which is what matters. And frankly the Cat is quite dangerous on most period apropos 70s/80's servers if its flown by a competent pilot at least. But you are right the days of the "I win button" are over and that probably makes some people sad.

That's exactly what I was going to say. Why do you need 54 pages of charts and formulas if the developer has already solved everything? This plane belongs on cold war servers. Empty and lifeless.

[Naquaii]

22 hours ago, Sindar said:

That's exactly what I was going to say. Why do you need 54 pages of charts and formulas if the developer has already solved everything? This plane belongs on cold war servers. Empty and lifeless.

The real question is what you're doing here, the solution to your problem would be to not read this thread. The other people in here seem perfectly happy about their discussion.

[bernyssen]

En 2/12/2023 a las 14:07, Sindar dijo:

That's right. Incentivize the sale of goods no one wants so they don't take up shelf space. It is not necessary to incentivize the sale of good goods. It will always be bought. And there will always be a shortage of it. It's called high demand. There's no demand for F-14s.

 

P.S. 30% off. My mistake.

*cough cough*

[LTC123apple]

On 12/5/2023 at 12:23 PM, Sindar said:

That's exactly what I was going to say. Why do you need 54 pages of charts and formulas if the developer has already solved everything? This plane belongs on cold war servers. Empty and lifeless.

oh bless your heart

 

cold war is one of the most popular kinds of servers, and will almost certainly get 10x as popular with the (so far looking amazing!) f4e module

as for the f14 needing more charts and formula, the facts are with a product like this there is always room to improve, so more info being out there (as long as we dont got warthunder moments) is good for the devs (who are very much still planning to and currently still supporting the product!)

 

I really do not understand what you are complaining about

Edited December 7, 2023 by LTC123apple

[cheezit]

16 hours ago, LTC123apple said:

oh bless your heart

 

cold war is one of the most popular kinds of servers, and will almost certainly get 10x as popular with the (so far looking amazing!) f4e module

as for the f14 needing more charts and formula, the facts are with a product like this there is always room to improve, so more info being out there (as long as we dont got warthunder moments) is good for the devs (who are very much still planning to and currently still supporting the product!)

 

I really do not understand what you are complaining about

 

How far off is the current MiG-21bis module from a realistic Vietnam configuration (MiG-21F-13)?  It's got a bigger engine at a minimum, right?

[Quid]

On 12/2/2023 at 1:07 PM, Sindar said:

That's right. Incentivize the sale of goods no one wants so they don't take up shelf space. It is not necessary to incentivize the sale of good goods. It will always be bought. And there will always be a shortage of it. It's called high demand. There's no demand for F-14s.

 

P.S. 30% off. My mistake.

https://www.digitalcombatsimulator.com/en/shop/modules/filter/sort-is-popular/apply/

Of modules actually released (the F-4 is pre-order), the F-14 is still in the top 5, so I'd say the demand is still pretty high.

[Harlikwin]

On 12/8/2023 at 7:54 AM, cheezit said:

How far off is the current MiG-21bis module from a realistic Vietnam configuration (MiG-21F-13)?  It's got a bigger engine at a minimum, right?

Well, its pretty apples and oranges.

Aerodynamically the F-13 was much lighter and more maneuverable than the bis, but had a weaker engine. The bis is kind of a pig compared to the F13 aerodynamically and much heavier. Otherwise the F13 was basically a guns  fighter, but in VN service it could carry 2 R3S (improved aim9B) missiles. Unlike the Bis it had no radar beyond a rangfinder for the gun, and weird canopy arrangement as well (poor forward view). The DCS bis is a very poor stand-in for a VN era F-13... 

And overall the bis in DCS is quite dated and has a bunch of problems and inaccuracies with alot of its systems.