Phantom vs XXX

[SuperKermit]

Am 13.1.2023 um 15:58 schrieb SgtPappy:

I suppose you are actually saying why we don't need aircraft-specific parameters in the formula? The calculations I provided don't require parameters like C_L, C_D etc because they are saying that: "given that an aircraft can pull n G's at speed v, what is its turn radius?" That is, the formulas are just basic kinematic formulas that work on anything that is turning. It assumes that the values you plugged in can be achieved by whatever aircraft/car/boat/thing you are calculating it for.

That’s exactly what I meant! Thank you for the clarification

[Czechnology]

Math nerds, just pull the friggin stick and turn the bird, who cares about AoA indicators

Edited January 15, 2023 by Czechnology

[G.J.S]

11 hours ago, Czechnology said:

Math nerds, just pull the friggin stick and turn the bird, who cares about AoA indicators

 

When you get the F-4, you will realise that the AoA gauge will show you when you are doing well - or your aircraft is about to start chasing its own tail, and you are just an unfortunate, regretful passenger.

[Bozon]

17 hours ago, G.J.S said:

When you get the F-4, you will realise that the AoA gauge will show you when you are doing well - or your aircraft is about to start chasing its own tail, and you are just an unfortunate, regretful passenger.

Nonsese!

Pull that stick in a love embrace, fire all of your guns at once and explode into space!

[SgtPappy]

On 1/15/2023 at 6:35 AM, Czechnology said:

Math nerds, just pull the friggin stick and turn the bird, who cares about AoA indicators

 

[Aussie_Mantis]

On 1/16/2023 at 9:35 AM, G.J.S said:

When you get the F-4, you will realise that the AoA gauge will show you when you are doing well - or your aircraft is about to start chasing its own tail, and you are just an unfortunate, regretful passenger.

What should I keep the AoA at? I know unslatted F-4s fly differently but I hear that going over 20 is tantamount to suicide.

 

On 1/17/2023 at 3:04 AM, SgtPappy said:

NEEEERRRRDDDD.

Also do you have any idea of how MiG-21 vs F-4 should go? Mate of mine really wants to fly MiG vs F-4E and it's all he talks about

 

[Fjordmonkey]

On 1/16/2023 at 12:35 AM, G.J.S said:

When you get the F-4, you will realise that the AoA gauge will show you when you are doing well - or your aircraft is about to start chasing its own tail, and you are just an unfortunate, regretful passenger.

Is it even possible to be a regretful passenger in a Phantom? Asking for a friend

[Kalasnkova74]

12 hours ago, Aussie_Mantis said:

Also do you have any idea of how MiG-21 vs F-4 should go? Mate of mine really wants to fly MiG vs F-4E and it's all he talks about

 

Not the quoted poster, but that contest will come down to pilot skill. 

[Czechnology]

14 hours ago, Aussie_Mantis said:

Also do you have any idea of how MiG-21 vs F-4 should go? Mate of mine really wants to fly MiG vs F-4E and it's all he talks about

 

Very much what Kalasnkova said. F-4 enjoys a higher top speed and much more missiles carried in a single sortie, Mig-21 Bis enjoys a better turning ability in the hands of a veteran and better acceleration overall. Can't say how much of an advantage, best place to find people with real 21 knowledge is Enigma's cold war server, but good luck getting information other than essentially "Mig-21 > {INSERT BLUFOR AIRCRAFT} my 1 to 1 thrust to weight-o-rino with the emergency AB!!!"

Personal plan is to keep it high and fast. In theory the F-4 has such a high top speed the 21 is physically incapable of keeping up without choking its engine.

[SgtPappy]

1 hour ago, Czechnology said:

Very much what Kalasnkova said. F-4 enjoys a higher top speed and much more missiles carried in a single sortie, Mig-21 Bis enjoys a better turning ability in the hands of a veteran and better acceleration overall. Can't say how much of an advantage, best place to find people with real 21 knowledge is Enigma's cold war server, but good luck getting information other than essentially "Mig-21 > {INSERT BLUFOR AIRCRAFT} my 1 to 1 thrust to weight-o-rino with the emergency AB!!!"

Personal plan is to keep it high and fast. In theory the F-4 has such a high top speed the 21 is physically incapable of keeping up without choking its engine.

From what I remember this is more true for the hard-wing F-4.

From the plots, the slatted Phantom has a better maximum sustained turn rate even against a MiG-21 using emergency burner. However if the Phantom slows down under, say ~350 KIAS, the MiG has a better sustained rate and the gap increases as the Phantom slows.

The top speeds (more specifically the 1G flight envelopes) appear to be close since the slats add some drag. The F-4E has a higher speed limit to 36,000' but the MiG-21 can fly higher. With all 8 missiles, I suspect the Phantom might be a hair slower or just about the same all the way up to 36,000' than a MiG with 4xR-60s or 4xR-3s (the more historically accurate loadout for the early 1970s). I don't know if the MiG-21bis in DCS can fly past that temperature limit line though... if so it would be faster up high where the F-4E with slats can't climb to. Note that the hard-wing F-4E does not have this disadvantage.

Instantaneous turn rate is in favour of the MiG by a decent but not crazy amount, IMO. Below is a graph I made a long time ago based on manual data, interpolated where applicable:

 

Maybe I'll eventually make an overlay but here are the plots form the Russian MiG-21bis manual and the 1979 TO 1F-4E-1:

 

Edited January 19, 2023 by SgtPappy

[Aussie_Mantis]

On 1/20/2023 at 2:07 AM, SgtPappy said:

From what I remember this is more true for the hard-wing F-4.

From the plots, the slatted Phantom has a better maximum sustained turn rate even against a MiG-21 using emergency burner. However if the Phantom slows down under, say ~350 KIAS, the MiG has a better sustained rate and the gap increases as the Phantom slows.

The top speeds (more specifically the 1G flight envelopes) appear to be close since the slats add some drag. The F-4E has a higher speed limit to 36,000' but the MiG-21 can fly higher. With all 8 missiles, I suspect the Phantom might be a hair slower or just about the same all the way up to 36,000' than a MiG with 4xR-60s or 4xR-3s (the more historically accurate loadout for the early 1970s). I don't know if the MiG-21bis in DCS can fly past that temperature limit line though... if so it would be faster up high where the F-4E with slats can't climb to. Note that the hard-wing F-4E does not have this disadvantage.

Instantaneous turn rate is in favour of the MiG by a decent but not crazy amount, IMO. Below is a graph I made a long time ago based on manual data, interpolated where applicable:

 

Maybe I'll eventually make an overlay but here are the plots form the Russian MiG-21bis manual and the 1979 TO 1F-4E-1:

 

 

So what you're telling me is to never attempt BFM against a Gen 4?

That's stupid. You're stupid. I will fight a MiG-29 in BFM. It'll be funny, trust me. I'm taking bets on 30 seconds post merge.

 

Edited January 20, 2023 by Aussie_Mantis

[Kalasnkova74]

17 hours ago, Aussie_Mantis said:

So what you're telling me is to never attempt BFM against a Gen 4?

That's stupid. You're stupid. I will fight a MiG-29 in BFM. It'll be funny, trust me. I'm taking bets on 30 seconds post merge.

 

 

Defeating a MiG-29 with an F-4E is a simple, if patient process. Just stay in min AB and wait for the Fulcrum to go joker. 

[foxmagnet]

2 hours ago, Kalasnkova74 said:

Just stay in min AB and wait for the Fulcrum to go joker. 

Legit tactic man

I'm sure F-4 can out fuel most if not every MiGs in DCS

[Sarge55]

And if there are two?   Asking for a friend…

[SgtPappy]

On 1/20/2023 at 11:41 AM, Aussie_Mantis said:

So what you're telling me is to never attempt BFM against a Gen 4?

That's stupid. You're stupid. I will fight a MiG-29 in BFM. It'll be funny, trust me. I'm taking bets on 30 seconds post merge.

 

 

Your ego is writing (virtual) cheques your (virtual) body can't cash!

[Aussie_Mantis]

On 1/24/2023 at 10:12 AM, SgtPappy said:

Your ego is writing (virtual) cheques your (virtual) body can't cash!

You misunderstand.

 

30 seconds not for the Fulcrum to be dead

30 seconds survival until the Fulcrum guns me down

[Gwalker99]

On 2/1/2022 at 9:25 PM, divinee said:

I created this topic to compare different F-4 versions to different aircrafts. The main point is to learn how to fly phantom against various enemy aircrafts. 

This topic will be a continuation from the page 8 and 9 discussion of the "Announcing the F-4 Phantom for DCS World!" @BIGNEWY @NineLine maybe you can move those posts here if possible?

 

Edit: We don't want to start to argue which aircraft is better and please keep the discussion civil.

 

Allegedly, the Phantom pilots were told to execute a series of 4-5 G maneuvers while trying to stay above 450 because after about 2 to 3 transitions, the 21's bleed way way more energy from the ACM compared to the Phantom due to the 21's wing design and then they have to go defensive to gain energy back to continue and that's when the Phantom can pounce 

[Kalasnkova74]

2 hours ago, Gwalker99 said:

Allegedly, the Phantom pilots were told to execute a series of 4-5 G maneuvers while trying to stay above 450 because after about 2 to 3 transitions, the 21's bleed way way more energy from the ACM compared to the Phantom due to the 21's wing design and then they have to go defensive to gain energy back to continue and that's when the Phantom can pounce 

Couple of disclaimers. One, this tactic was run with two US Navy Phantom IIs. One would dive down to pressure the MiG to turn, and the other would be climbing to gain energy before committing to their own attack. This would work against a single MiG-21 driver inexperienced in BFM (which was most of the NVAF).  Against a single trained bandit or team of them, not so much. 
A smart MiG driver won’t let a Phantom II kill their energy until it suits the Fishbed’s fight. As proved by the 4477th TES the MiG just has to threaten the nose enough to get the F-4 to make a sub-optimal turn (or force a horizontal scissors) . With every knot lost the MiG gains the advantage.

 

Ultimately F-4 vs MiG-21 is going to be a pilot skill contest. 

[some1]

Until you try to fight against AI MiG-21 in DCS, that bugger can sustain 6-7g turns all day long. 

[Kalasnkova74]

23 hours ago, some1 said:

Until you try to fight against AI MiG-21 in DCS, that bugger can sustain 6-7g turns all day long. 

Today I strapped in VSN's F-4C mod and went up against an AI Mig-21BIS & Mig-29. Both on "Veteran" difficulty. Neither track file is going to put Tom Cruise out of work, but the bandits clocked 2nd place. 

F-4 vs Mig-21 BIS.trk F-4 vs Mig-29.trk

Edited February 5, 2023 by Kalasnkova74

[some1]

My comment was not meant to start a pissing contest about who can shot down what in DCS, rather a caution about trying to use real world tactics and tricks against DCS AI. 

[SgtPappy]

In order to continue this discussion based on a question in another thread here from @Aussie_Mantis, I'm going to post what I've learned so far concerning the F-4E vs the Viggen, MiG-19 and the Mirage F1C. I invite others with more information to add. I'd like to disclose that this analysis only holds water in DCS if in-game versions perform close enough to these graphs. Additionally, this is once again primarily an pseudo-academic exercise in comparing the jets from an engineering and physics-based standpoint and we all know that tactics and pilot skill matter the most in a fight. Anyway, we've seen some great work when HB adjusted the F-14 and Viggen FM's so I have confidence that all their jets will be accurate if not already.

AJS37 vs F-4E

This one is going to be a bit of speculation due to a couple of assumptions, but I believe the guess is educated enough to yield some realistic expectations. Any Viggen experts, please chime in if you would like to share more.

For the Viggen, we have a couple manuals, one for the AJ37 here (big thanks to @widen76 and @renhanxue) which has a lot of data. Unfortunately it does not have direct turn rate data for the AJ37 but, there is a speciell förarinstruktion SFI manual which I cannot post here for the JA37 since it's from 1983 that has several turn rate plots at different configurations. My first assumption is that the AJ37, AJS37 and JA37 are virtually identical aerodynamically as it relates to subsonic turn rates. One of the turn rate diagrams in the latter manual shows a clean JA37 at 40% fuel among many other configurations at SL, 4 km, 8 km and 12 km altitude. Both the aforementioned manuals have lots of data for different configurations and I noticed that a clean JA37 at 40% fuel had approximately the same weight as an AJ37 Viggen at 70% fuel (~13600 kg = 30000 lbs). Conveniently, the TO 1F-4E-1 has a plot of the F-4E with 4xAIM-7E's and ~63% fuel (for anyone new to the discussion, this has been posted several times, including earlier in this thread). This weight is 42,777 lbs is approximately the F-4E's weight clean with 70% fuel. This graph therefore is a bit more conservative in favour of the Viggen since the F-4E weighs the same as it would clean at 70% fuel, but with the added drag of AIM-7's.

If we compare the sustained turn rates of the graphs in the F-4E's -1 and the JA37 Viggen 1983 performance manual, we estimate that the 40% fuel clean JA37 can attain a maximum STR of ~14.2 deg/s at ~Mach 0.73 or so. The F-4E's plots shows a 14.7 deg/s turn rate at ~Mach 0.78. Now what we do know as well is that the AJ(S)37 has a slightly weaker engine and that the F-4E here has a tiny bit more drag than clean so if we were to clean the F-4E but maintain the weight by adding fuel and decrease the thrust for the Viggen to reflect an AJ(S)37, we know that the F-4E must have an even better sustained turn rate than what we have just visually compared on the graphs. It won't be absolutely massive, but if I estimate it at being ~0.5 deg/s or more, then it will be noticeable with two pilots who are competent in the rate fight. Note that as speed gets slower, the JA37 slowly loses STR while the the F-4E's drops faster so the F-4E will have to stay fast to keep its small STR advantage.

If we compare the instantaneous turn rates of both fighters, things get a bit messy. Another AJ/JA37 (Fpl aerodynamik III) manual from 1981, we see that at SL, the AJ(S)37 hits 4G at ~Mach 0.4 and that the F-4E reaches 4G at ~Mach 0.48 at 42,000 lbs (fig 5-9 in the TO below). These are estimated since I can't read Swedish so I don't know at what weight the Viggen is at. Also figure 5-9 in the F-4E TO is ambiguous since it's the same plot as in the hard-wing 1F-4C-1 manual. There are no plots for the slatted F-4E at SL and at any other weight than 37,500 lbs which is too light. I may extrapolate F-4E ITR data by calculating CL_max on the given Vn plot lift curves and then applying a larger weight to estimate the ITR at, say, 50% fuel clean but I need to find an AJ(S)37 ITR plot at a specified weight as well to make a comparison. So here, I estimate that the Viggen has an even better ITR than the F-5E and MiG-21, making it the best turn rate of this era of jets. As an added point of interest, the JA37 has an engine that is more capable of handling high AoA so it can pull crazy high instantaneous turn rates (i.e. 5G at ~Mach 0.4 at SL, clean, 80% fuel). I do know that the DCS AJS37 experiences compressor stalls at high AoA but to what degree, I'm not sure so perhaps it can reach similar turn rates at the risk of flameout.

 

Comparing speed, see the AJ37 level envelope to the F-4E's below. We can see that they have the same max allowed speed at SL, with the F-4E outpacing the AJ(S)37 as altitude increases for ISA day conditions. Max Mach for the AJ(S)37 is ~Mach 1.82 at ~36000 ft, with the F-4E reaching ~Mach 2.04 at 36000 ft. Adding weapons will change this but the jets are fairly comparable. Acceleration and climb rates are very, very close when comparing the AJ(S)37 plots with those of the F-4E.

 

 

In summary, I believe the Viggen - with its 1 circle performance that rivals even 4th gen jets if it doesn't suffer a compressor stall - will be tough for the F-4E which will have to counter with 2 circle fighting at higher speeds and lobbing AIM-7's to get to an advantageous merge. As an aside, the hard-wing F-4E and J plots imply that they have large advantages in climb, acceleration and speed but are far inferior in turning capabilities.

 

MiG-19P vs F-4E

This is tough because I don't have a single shred of data for the MiG-19's performance like I do for the MiG-21SM/MF/bis. If anyone has any performance plots, please share! However, we know that MiG-19 has a very high T:W ratio, exceeding the F-4E's and has a low wing loading so it likely has superior ITR and STR. However, being barely capable of Mach 1.2, it is probably easily outpaced at higher speeds by the F-4E. The F-4 strategy is therefore simple vs the MiG-19 - boom and zoom and never get slow. Otherwise be prepared to die, like if you were to turn fight a Spitfire in an F-86 or MiG-15.

 

Mirage F1 series vs F-4E

I had posted a similar analysis for this elsewhere but am too lazy to find it. The Mirage F1C has a very similar wing sweep and aspect ratio, as well as half span flaps and half span slats. The Mirage F1 has a conventional (for the era) tube-shaped fuselage with no LERX or lifting body features. Wing loading is higher than that of the F-4E and T:W is lower. It is almost certainly going to turn worse in both ITR and STR than the F-4E. Published figures on its speed imply it has a faster top speed (~Mach 2.2). The lack of graphs available however make it difficult to directly compare turn and speed performance at different altitudes. Based on how it performs vs the MiG-21 in DCS, I believe the F-4E will out-rate it with some margin, while the Mirage may be better extending in the vertical if it keeps its speed high. 

 

 

Edited July 4, 2023 by SgtPappy

[Smyth]

13 hours ago, SgtPappy said:

MiG-19P vs F-4E

 

This is tough because I don't have a single shred of data for the MiG-19's performance like I do for the MiG-21SM/MF/bis. If anyone has any performance plots, please share! However, we know that MiG-19 has a very high T:W ratio, exceeding the F-4E's and has a low wing loading so it likely has superior ITR and STR. However, being barely capable of Mach 1.2, it is probably easily outpaced at higher speeds by the F-4E. The F-4 strategy is therefore simple vs the MiG-19 - boom and zoom and never get slow. Otherwise be prepared to die, like if you were to turn fight a Spitfire in an F-86 or MiG-15.

I don't have any real-world data to add on this one, but I do have an observation from the game. Surprisingly enough, the Mig-19 has worse ITR than the Mig-21 and other supersonic jets. I don't have the module, but from watching experienced pilots in cold war multiplayer, the winning Mig-19 strategy is to patiently build an energy advantage with sustained turns and loops. Other aircraft like the F-5 can not only survive at close quarters, but pose a serious threat until the -19 powers away in the vertical. It is a very different fight than an F86 or Mig-15.

[SgtPappy]

9 hours ago, Smyth said:

I don't have any real-world data to add on this one, but I do have an observation from the game. Surprisingly enough, the Mig-19 has worse ITR than the Mig-21 and other supersonic jets. I don't have the module, but from watching experienced pilots in cold war multiplayer, the winning Mig-19 strategy is to patiently build an energy advantage with sustained turns and loops. Other aircraft like the F-5 can not only survive at close quarters, but pose a serious threat until the -19 powers away in the vertical. It is a very different fight than an F86 or Mig-15.

That's very interesting! I didn't realize that. I wonder if this is the case for a real MiG-19. If so, I wonder if the vortex lift that would usually be generated by a swept wing with a sharp leading edge is absent for the MiG-19 design due to maybe a blunt leading edge or the wing fences preventing spanwise flow.

[renhanxue]

On 7/4/2023 at 3:25 AM, SgtPappy said:

If we compare the instantaneous turn rates of both fighters, things get a bit messy. Another AJ/JA37 (Fpl aerodynamik III) manual from 1981, we see that at SL, the AJ(S)37 hits 4G at ~Mach 0.4 and that the F-4E reaches 4G at ~Mach 0.48 at 42,000 lbs (fig 5-9 in the TO below). These are estimated since I can't read Swedish so I don't know at what weight the Viggen is at.

The document doesn't say. If I had to guess I'd say 70% fuel because that's the standard used for the in-flight diagrams in the SFI, but it's far from certain. The aerodynamics compendium has two parts and the graphs in the other part frequently use specific weights to illustrate some point, but then it's always stated what that weight is. So, I really don't know.

According to the aerodynamics compendium the RM8A (on the AJ 37) starts compressor stalling at around 20° alpha, leaving only a small margin of error from the limit of 18°. I don't know how the DCS implementation does these days. The RM8B in the JA 37 is significantly better; the alpha limit is 23° and the engine reportedly does not start compressor stalling below 25°, which is the point where the aircraft starts losing longitudinal stability and you risk superstall or spin. That means the AJS 37 should not be able to reach the JA 37's level without compressor stalling even if you exceed the 18° limit significantly.

I don't have much to add; if anything I think you might be slightly too generous to the AJS 37 in terms of sustained turn rate, but that's just gut feeling, no numbers to back it up.

It's really a pity that we don't have a good JA 37 simulator...

Edited July 5, 2023 by renhanxue