F-4E Phantom Phamiliarisation (whilst we wait for DCS..)

[Karon]

Hey folks!

The SE is out, the F-4 looms just beyond the horizon. The long watch is almost over… Possibly.

For this reason, I wanted to get a bit more familiar with the Phantom II, and I started with taking a look at the cockpits. The DCS F-4E is not out yet, the old screenshots from Belsimtek are not great, so I have found an alternative, and put together a quick video.

Moving the first steps with a new aeroplane is never easy, especially if the game does not match either. I have used MilViz's F-4 for FSX, and this seems to be a DVST Phantom, whereas I am looking forward to the later upgrades, to fit in the best period DCS can imo replicate (late 70s, early 80s). Nevertheless, the difference should not be huge, and this is a good means of familiarising with the cockpit.

I am sure there are errors in the video, as I am brand new to the Phantom and I have spent only a dozen hours studying the documentation. So, if you have observations, please do share them, and I will put the corrections in the comments.

Thanks!

UPDATE 10/07/2023: GUNS & SLATS

The F-4E featured two peculiar upgrades that separate it from the predecessors and its Navy brothers: the presence of an internal gun, and the nre wing supporting leading-edge slats.

UPDATE 14/07/2023: AIR-TO-AIR WEAPONS EMPLOYMENT

An overview of the basic avionics and instrumentation required to employ AIM-7 Sparrow, AIM-9 Sidewinder and the M61A1 20mm Vulcan.

UPDATE 23/07/2023: RADAR BASICS & CONTROLS

The details of the Radar Set Control Panel, and the purpose of the instruments here installed.

UPDATE 03/08/2023: RADAR QUIRKS & FEATURES

A discussion about some cool features of the radar and avionics, such as the nutating antenna pattern, or the Computer Automatic Acquisition mode.

UPDATE 17/08/2023: AIR-TO-AIR INTERCEPTS - THEORY

A two-parts refresher on the basic concepts useful to intercept and engage a target with the F-4E Phantom II. This first video covers the theory.

UPDATE 29/08/2023: AIR-TO-AIR INTERCEPTS - PRACTICE

The second part of the Air-to-Air Intercepts sees some practical examples using the F-14's DDD B-Scope in Pulse mode.

 

Edited August 29, 2023 by Karon
Added video VII

[Q3ark]

That was a great video.
 

I’m torn about the phantom, it’s heatblur so it’ll be an amazing module but that office is just awful. 

[G.J.S]

4 hours ago, Q3ark said:

 . . . but that office is just awful. 

You will get used to it.
Admittedly, it’s easier ‘starting’ on steam gauges and graduating to MFD’s and elec-trickery, but a little harder the other way round.

The younger generation may have to train somewhat to attain a good cockpit scan method - the frequent “lookdowns” to check state and trend before certain points, for example prior to the merge, IN the merge, in the pattern, the list goes on!

Aircrews since the mid ‘90’s have been truly blessed with the plethora of information readily available at eye level. Cockpit design and ergonomics have come on hundred-fold.

The F-4 will treat you to an aircraft that will co-exist happily with you should you respect her. Just like a woman though, let your attention wander and she will bite.

The cockpit does have all the info you need right there, you will have to practice and perfect your quick scan to assimilate what’s happening, what’s going to happen, and act accordingly. 
 

A few flights under your belt and once you get used to where some things are, you will enjoy the challenge of taming a thoroughbred.

[Q3ark]

I see what you’re saying and it’s very true. I fly the DC-6 quite often in the civilian flight sim when I want to relax. 
 

the main thing that is bothering me is the poor vis out of the front and the WISO has no chance, don’t know why they even bothered to give him a clear canopy lol. 

[SgtPappy]

19 hours ago, Q3ark said:

That was a great video.
 

I’m torn about the phantom, it’s heatblur so it’ll be an amazing module but that office is just awful. 

I remember having to get used to the F-14's 3 piece windshield and having lots of trouble seeing the enemy in BFM. 

That said, I thought the rearward visibility in the F-4 would be even worse than in the video.. the F-5 and MiG-21 are not great in those departments but it looks like the F-4 WSO has a modest ability to see behind!

14 hours ago, G.J.S said:

The cockpit does have all the info you need right there, you will have to practice and perfect your quick scan to assimilate what’s happening, what’s going to happen, and act accordingly. 
 

A few flights under your belt and once you get used to where some things are, you will enjoy the challenge of taming a thoroughbred.

I actually like some elements of the F-4's post TO 556 mod ergonomics than modern planes. The early F-16 and F-14 have a very inconveniently-placed radar display but the F-4's repeater is right in your face.

Edited July 7, 2023 by SgtPappy

[Karon]

After reviewing the cockpit multiple times, I started to like it and get its logic (I'm talking about the Nav, of course). The majority of the controls follow a pattern, plus some oddly placed, which may have been located there following upgrades. Still, it looks much more intuitive than some Soviet cockpits.

[Bremspropeller]

Keep in mind that your most probable opponets will also be constrained by a cockpit-visibility akin to a cast iron letterbox.

[Karon]

True, although the F-4E has been around for so long that it mostly depends on the mission and scenario.

 

Unrelated, I have put together another quick video, focused on two of the main peculiarities of the F-4E: Guns & Slats.

[Karon]

I have changed the purpose of the topic a little, and posted another video here, to limit the number of threads. Hope you like it!

[Karon]

Added video IV and V.

Hopefully, I am not the only one to be excited about stuff like this:

[Rudel_chw]

12 minutes ago, Karon said:

Added video IV and V.

Thanks a lot for doing this series 

[_BringTheReign_]

3 hours ago, Karon said:

Hopefully, I am not the only one to be excited about stuff like this:

This is excellent. Your videos are very digestible and provide an excellent background in advance of module release. Thank you for doing this!

[SgtPappy]

7 hours ago, Karon said:

Added video IV and V.

Hopefully, I am not the only one to be excited about stuff like this:

Incredible as always. These videos always make my day.

Having just watched video 4 about the radar basics, I see that you mention the aspect knob helps tune the Sparrow to search for a specific part of the Doppler spectrum of the target return upon launch. Would you be able to elaborate on this? I was under the impression that this would require frequency filter bins or Fourier transforms of some sort which I thought were only possible when the radar emits with pulse-to-pulse coherence which the APQ-120 does not (i.e. the failure of CORDS to be implemented). 

[Smyth]

On 8/3/2023 at 9:52 AM, SgtPappy said:

I see that you mention the aspect knob helps tune the Sparrow to search for a specific part of the Doppler spectrum of the target return upon launch. Would you be able to elaborate on this? I was under the impression that this would require frequency filter bins or Fourier transforms of some sort which I thought were only possible when the radar emits with pulse-to-pulse coherence which the APQ-120 does not (i.e. the failure of CORDS to be implemented). 

I am not an electrical engineer, but let me attempt to explain, because the aspect knob is one of the most interesting features on the F4 and F14 radar.

The difficulty of pulsed doppler radar processing is that it has to transform the time-domain output of a pulsed radar into the frequency domain, and bin that frequency domain spectrum into different doppler speeds to provide a useful search function that can display the angle and velocity of multiple targets within the scan volume. Try to add back range information (time domain) for RWS, and it gets even more difficult (hence the APG-59 in the F-4J provided only velocity search).

The CW illumination strategy used by the Sparrow avoids that complexity (Fourier transforms and any kind of filter bins) by ... not doing any of those things.

• It separates the transmit and receive antenna so that the illumination can be continuous and pulse-to-pulse coherence is irrelevant.
• It operates only in the frequency domain, without any way to provide range information. <- edit: this statement is incorrect, it can use FM ranging
• It does not analyze the entire doppler frequency spectrum, only filter ('speed gate') returns to a specific range and home on the direction of the strongest return in that range.

Also, this simplistic two-antenna doppler radar does not actually care if there is a search radar guiding it. The first versions of the RIM-7 Sea Sparrow could be used to upgrade optically-aimed AA turrets, where the operator simply aimed an illumination antenna at the target and the Sparrow guided toward that target with its own seeker as the only radar processing in the entire system.

I don't think Karon mentioned in his video that the original purpose of the aspect knob for the APQ-120 is to guide a Sparrow with no range track, or even no radar track at all. That could be useful against electronic warfare if the radar can acquire an angle track but no range track, if the radar is malfunctioning but the CW illumination still works, or even to guide an Aim-7 into heavy clutter (airborne chaff, weather, or ground) where the pulse radar of the F-4B/C/D/E cannot acquire any radar lock at all. In that case the WSO 'locks' the radar straight ahead, and the pilot aims the whole plane like a RIM-7 turret. Without range-rate information from the radar, the WSO uses the aspect knob to let the Sparrow know if it should filter for closing-aspect targets or opening-aspect targets, to avoid locking onto stationary clutter. The "wide" aspect sweeps the whole doppler frequency range and would only be useful looking up into clear sky.

Aiming the narrow radar beam at a point is only going to be practical for non-maneuvering targets, so it's clear the feature was intended for intercepting bombers flying through a cloud of defensive chaff, or in the case of radar malfunction on an intercept mission carrying only Sparrows. In a game it would be pretty amusing to use it against fighters flying in ground clutter, which would be unlikely to work well but might scare them at least. Add an optical angle track from TISEO into the mix, and now you have something a bit more dangerous. Unfortunately I don't think DCS in its current state can simulate that level of seeker complexity.

Because this feature is very much a corner case in normal operations, the designers re-used the aspect knob to adjust the function of the range rate display. A lot of switches in the Phantom cockpit are re-used like that to pack in analogue systems without the benefit of an MFD.

Edited August 12, 2023 by Smyth
correction

[SgtPappy]

6 hours ago, Smyth said:

I am not an electrical engineer, but let me attempt to explain, because the aspect knob is one of the most interesting features on the F4 and F14 radar.

The difficulty of pulsed doppler radar processing is that it has to transform the time-domain output of a pulsed radar into the frequency domain, and bin that frequency domain spectrum into different doppler speeds to provide a useful search function that can display the angle and velocity of multiple targets within the scan volume. Try to add back range information (time domain) for RWS, and it gets even more difficult (hence the APG-59 in the F-4J provided only velocity search).

The CW illumination strategy used by the Sparrow avoids that complexity (Fourier transforms and any kind of filter bins) by ... not doing any of those things.

• It separates the transmit and receive antenna so that the illumination can be continuous and pulse-to-pulse coherence is irrelevant.
• It operates only in the frequency domain, without any way to provide range information.
• It does not analyze the entire doppler frequency spectrum, only filter ('speed gate') returns to a specific range and home on the direction of the strongest return in that range.

Also, this simplistic two-antenna doppler radar does not actually care if there is a search radar guiding it. The first versions of the RIM-7 Sea Sparrow could be used to upgrade optically-aimed AA turrets, where the operator simply aimed an illumination antenna at the target and the Sparrow guided toward that target with its own seeker as the only radar processing in the entire system.

I don't think Karon mentioned in his video that the original purpose of the aspect knob for the APQ-120 is to guide a Sparrow with no range track, or even no radar track at all. That could be useful against electronic warfare if the radar can acquire an angle track but no range track, if the radar is malfunctioning but the CW illumination still works, or even to guide an Aim-7 into heavy clutter (airborne chaff, weather, or ground) where the pulse radar of the F-4B/C/D/E cannot acquire any radar lock at all. In that case the WSO 'locks' the radar straight ahead, and the pilot aims the whole plane like a RIM-7 turret. Without range-rate information from the radar, the WSO uses the aspect knob to let the Sparrow know if it should filter for closing-aspect targets or opening-aspect targets, to avoid locking onto stationary clutter. The "wide" aspect sweeps the whole doppler frequency range and would only be useful looking up into clear sky.

Aiming the narrow radar beam at a point is only going to be practical for non-maneuvering targets, so it's clear the feature was intended for intercepting bombers flying through a cloud of defensive chaff, or in the case of radar malfunction on an intercept mission carrying only Sparrows. In a game it would be pretty amusing to use it against fighters flying in ground clutter, which would be unlikely to work well but might scare them at least. Add an optical angle track from TISEO into the mix, and now you have something a bit more dangerous. Unfortunately I don't think DCS in its current state can simulate that level of seeker complexity.

Because this feature is very much a corner case in normal operations, the designers re-used the aspect knob to adjust the function of the range rate display. A lot of switches in the Phantom cockpit are re-used like that to pack in analogue systems without the benefit of an MFD.

Thank you for this great write-up! I tend to have bits and pieces of information on things, like the AIM-7, but sometimes I simply don't manage to put two and two together!

But let me see if I understand this properly... Do you think that maybe at least some of the historical AIM-7 misses are due to the aspect switch supplying the AIM-7 with one bandwidth of frequencies but then the target changes aspect enough such that its return is out of the expected bandwidth and the AIM-7 goes ballistic? I then wonder if the aspect switch is used only before launch and that the changing spectrum of the return on a maneuvering target is transmitted into the AIM-7's tail receiver while in flight.

This makes sense to me since the Sparrow (not sure about the M, MH and P) does not have range gating capability and therefore something getting between the transmitter (host/launch aircraft) and the target matching the frequency spectrum the AIM-7 is expecting could force the AIM-7 to follow that interfering object. I hope one day this will be modeled in DCS but for now, getting the F-4 in my hands will do  

Edited August 4, 2023 by SgtPappy

[Smyth]

7 hours ago, SgtPappy said:

But let me see if I understand this properly... Do you think that maybe at least some of the historical AIM-7 misses are due to the aspect switch supplying the AIM-7 with one bandwidth of frequencies but then the target changes aspect enough such that its return is out of the expected bandwidth and the AIM-7 goes ballistic? I then wonder if the aspect switch is used only before launch and that the changing spectrum of the return on a maneuvering target is transmitted into the AIM-7's tail receiver while in flight.

This makes sense to me since the Sparrow (not sure about the M, MH and P) does not have range gating capability and therefore something getting between the transmitter (host/launch aircraft) and the target matching the frequency spectrum the AIM-7 is expecting could force the AIM-7 to follow that interfering object. I hope one day this will be modeled in DCS but for now, getting the F-4 in my hands will do

Not acquiring the target doppler must have been a significant failure mode in the 60s, because one of the improvements made to the F-4 (all versions) radar during the early 70s was a delay relay that gave an Aim-7 more time to acquire the correct target doppler signal. The aspect switch should not normally be involved because it would only be used against non-maneuvering targets (eg. bombers) if the radar cannot acquire a lock. I guess someone could accidentally set the switch to the 'wide' setting (the only position that overrides the radar) for no good reason, but I have no idea if it ever happened in real life.

A more likely reason for the speedgate not to lock properly would be if the aircrew does not wait the necessary delay for the radar to provide a stable simulated doppler to the missile. That is the sort of thing that can maybe be simulated on the module side in DCS, although the modules that should currently don't.

Regarding maneuvering targets, the missile updates its own speedgate after launch. The launching radar or the manual aspect knob only sets where it starts searching, and for better or worse they have no input after launch. To evade a CW homing SARH missile just by changing aspect, one must change closing velocity by more than the width of frequency range the seeker will sweep after launch, (about -/+150kts on the Sparrow) during the brief time (~1.5s) after the start of the launch sequence and before the missile attempts to lock on. Back-of-the-envelope trigonometry shows that is maybe possible but requires an aspect and turn rate that will probably put the target into the notch anyway.

[SgtPappy]

On 8/5/2023 at 12:46 AM, Smyth said:

Not acquiring the target doppler must have been a significant failure mode in the 60s, because one of the improvements made to the F-4 (all versions) radar during the early 70s was a delay relay that gave an Aim-7 more time to acquire the correct target doppler signal. The aspect switch should not normally be involved because it would only be used against non-maneuvering targets (eg. bombers) if the radar cannot acquire a lock. I guess someone could accidentally set the switch to the 'wide' setting (the only position that overrides the radar) for no good reason, but I have no idea if it ever happened in real life.

A more likely reason for the speedgate not to lock properly would be if the aircrew does not wait the necessary delay for the radar to provide a stable simulated doppler to the missile. That is the sort of thing that can maybe be simulated on the module side in DCS, although the modules that should currently don't.

Regarding maneuvering targets, the missile updates its own speedgate after launch. The launching radar or the manual aspect knob only sets where it starts searching, and for better or worse they have no input after launch. To evade a CW homing SARH missile just by changing aspect, one must change closing velocity by more than the width of frequency range the seeker will sweep after launch, (about -/+150kts on the Sparrow) during the brief time (~1.5s) after the start of the launch sequence and before the missile attempts to lock on. Back-of-the-envelope trigonometry shows that is maybe possible but requires an aspect and turn rate that will probably put the target into the notch anyway.

Very interesting stuff.

Theoretically, if the APQ-120 could track the target even looking down (say in a situation where SNR still allows the tracking loops to work), you could still shoot down as long as the target doppler is different from the ground return right?

I have heard that any shot below the horizon doesn't work but since the WSO/RIO can play with gain, I don't think thats necessarily true.

Edited August 8, 2023 by SgtPappy

[WarbossPetross]

14 часов назад, SgtPappy сказал:

Very interesting stuff.

Theoretically, if the APQ-120 could track the target even looking down (say in a situation where SNR still allows the tracking loops to work), you could still shoot down as long as the target doppler is different from the ground return right?

I have heard that any shot below the horizon doesn't work but since the WSO/RIO can play with gain, I don't think thats necessarily true.

 

Basically any radar can achieve a track in any scenario, the question is what distance it's going to be when it gets a contrast return. Which is probably going to be at a BFM range when you can see the target with your eyes, but it can still be useful when you can't see much at all, for example at night.

[Karon]

@SgtPappy sorry I am late, but I see that you had some excellent answers already, much better than I would have done. Thanks @Smyth!

Back to the question, I decided not to cover that particular functionality in the latest video (Part 5 - it is the bit I mentioned at the end of the video) because it is not implemented in DCS in the F-14, and it is a quite a niche but cool application. I will cover it if it changes in the future.

 

About the second question, Pulse can look-down-shoot-down in some scenarios. Feet-wet should be one of them because the ground clutter is reduced. We'll see how this is portrayed by HB in the F-4E.

[SgtPappy]

On 8/11/2023 at 7:04 AM, Karon said:

@SgtPappy sorry I am late, but I see that you had some excellent answers already, much better than I would have done. Thanks @Smyth!

Back to the question, I decided not to cover that particular functionality in the latest video (Part 5 - it is the bit I mentioned at the end of the video) because it is not implemented in DCS in the F-14, and it is a quite a niche but cool application. I will cover it if it changes in the future.

 

About the second question, Pulse can look-down-shoot-down in some scenarios. Feet-wet should be one of them because the ground clutter is reduced. We'll see how this is portrayed by HB in the F-4E.

Judging on how much attention to detail they're putting into the radar modeling, I hope so! Can't wait for the F-4 and your next video!

[Karon]

11 hours ago, SgtPappy said:

Judging on how much attention to detail they're putting into the radar modeling, I hope so! Can't wait for the F-4 and your next video!

Thanks!

I'm not sure what topic cover tbh. I don't want to touch the A/G part because there are too many variables involved (e.g. different pods, different upgrades, etc).

I was thinking about covering air-to-air intercepts, but it is nothing new and it would mostly be a repetition of the usual stuff

[Biggus]

15 hours ago, Karon said:

Thanks!

I'm not sure what topic cover tbh. I don't want to touch the A/G part because there are too many variables involved (e.g. different pods, different upgrades, etc).

I was thinking about covering air-to-air intercepts, but it is nothing new and it would mostly be a repetition of the usual stuff

Air-to-air intercepts is probably worth a refresher, at least within the context of the dearth of situational awareness tools at the Phantom crew's disposal.  But honestly, with the limited functionality of the AWACS scheme in DCS, I can completely understand why you'd hesitate to revisit the topic.

[Karon]

On 8/14/2023 at 7:26 AM, Biggus said:

Air-to-air intercepts is probably worth a refresher, at least within the context of the dearth of situational awareness tools at the Phantom crew's disposal.  But honestly, with the limited functionality of the AWACS scheme in DCS, I can completely understand why you'd hesitate to revisit the topic.

Yeah, controllers are fundamental with old hardware. The Tomcat managed, as it has an incredibly easy to use interface for the time, but the Phantom will have to rely a lot on locking targets to get the most basic information. The problem is, the AI immediately triggers the ECM every time it gets locked, so this will become annoying quite fast, I'm afraid.

Anyway, I guess I'll do something about AA intercepts. In preparation, I put together a banal video about radar scopes and the difference between B-scope and PPI. Nothing fancy, but I've been asked about it a few times, and understanding the B-scope is fundamental in the Phantom.

 

Edited August 15, 2023 by Karon
linked the wrong video *facepalm*

[Biggus]

8 hours ago, Karon said:

Anyway, I guess I'll do something about AA intercepts. In preparation, I put together a banal video about radar scopes and the difference between B-scope and PPI. Nothing fancy, but I've been asked about it a few times, and understanding the B-scope is fundamental in the Phantom.

 

Good video.  Not just because it's a solid refresher, but because it's very short and covers the concepts quite well.  Perfect for both newcomers wanting a basic explanation while they're overwhelmed with learning everything.

[Karon]

I put together something about the intercepts in the F-4. I decided to leave most of the "background information" out, focusing on the easy stuff. All the necessary in-depth explanation can be found in the links placed in the description of the video.

The next video will show some practical examples, using the DDD of the F-14. It is a bit different, of course, but it is the closest nonetheless.