What F-15C suite/block do we have in DCS? How old is it?

[SWPixivyle]

I don't have a lot of knowledge regarding the Eagle, and I was curious about the age of our F-15C. I didn't see it in the documentation. Considering the age of the module itself and what it looks like I'd assume early 2000s. If someone knows, I'd like to read it.

Edited July 15, 2022 by SWPixivyle

[Exorcet]

Given that it's not full fidelity, a definite year might not make sense. It's missing features from the real plane and in some cases grossly underperforming (radar). It could probably pass for a MSIP II upgraded Eagle from the mid 80's to the 90's. The 220 engine is modeled, so it couldn't represent a C Eagle before the mid 80's.

[SWPixivyle]

hace 2 horas, Exorcet dijo:

Given that it's not full fidelity, a definite year might not make sense. It's missing features from the real plane and in some cases grossly underperforming (radar). It could probably pass for a MSIP II upgraded Eagle from the mid 80's to the 90's. The 220 engine is modeled, so it couldn't represent a C Eagle before the mid 80's.

now that i think of it 2000s is way too late yeah, and i'm not surprised things don't match with this particular module due to it being low fidelity. agreed on the radar thing too

[henshao]

AMRAAM capability is one of the bigger clues, at the absolute earliest mid-87. lack of aim-9x support also bookends the other way but I'm not sure on that side

[draconus]

On 7/16/2022 at 12:33 AM, SWPixivyle said:

2000s is way too late

Unless you connect it to AIM-120C.

[okopanja]

5 hours ago, draconus said:

Unless you connect it to AIM-120C.

Well, for carrying AIM-120C is simply unrealistic. AIM-120C probably has more CPU computing power and RAM than original radar from 80s.

Still it makes great fun flying it fast and high and slinging its all those AMRAAMS at high speed at unsuspecting opposition.

Edited July 17, 2022 by okopanja
slight corrections...

[Northstar98]

Well, the manual states it should have AN/APG-63(V)1, which is 2003 at the earliest - coinciding with the AIM-120C-5.

Though suffice to say, it doesn't perform like one.

[henshao]

Must not be too late into 2003...

Quote

The TACTICAL LINK Volume 1 Issue 3 December 2003

The first operational Eagle unit with FDL, the 19th FS at Elmendorf AFB, Alaska, declared its Initial Operational Capability (IOC) in February of 2001. All operational and Air National Guard squadrons have declared IOC and all training squadrons are upgrading to the FDL configuration. FDL modification is now projected for completion almost a year ahead of schedule. As of this writing, over 600 F-15s (A through E configurations) have been modified and have FDL installed. Based on the success of FDL in the F-15, the Air Force made a decision in April 2001 to make all tactical platforms Link-16 capable.

 

---------

Fighters benefit from Link 16

• Published Sept. 26, 2003
• By 2nd Lt. Martha L. Petersante
• Electronic Systems Center Public Affairs

HANSCOM AIR FORCE BASE, Mass. (AFPN) --  A recent Electronic Systems Center effort has improved targeting accuracy and allowed air operations centers to change F-15 Eagle and F-15E Strike Eagle mission variables “on the fly.”

Members of the Tactical Data Link System Program Office equipped all 22 operational F-15 active-duty and Air National Guard squadrons -- more than 600 F-15s -- with Link 16 Fighter Data Link terminals.

 

[SilentSparrow]

If we add a datalink we could simulate a late 2003 F-15. Is the Datalink locked behind the files? If it isn't, the community could make a tablet that shows the datalink. Probably January 2003 is the model simulated in DCS.

[itzRadarDan]

First F-15Cs were modified to APG-63(V)1 in 2000.

[bies]

It's hard to tell because it's FC3 simplified aircraft. It's basically a mix of different variants. In manual its radar is named AN/APG-63(v)1, but it has capabilities of Cold War AN/APG-63 with PSP with only 4 targets simultaneous engagement.

It's at least 1985 MSIP II variant since it has 1985 standard avionics elements, radar with PSP and TWS mode, NCTR, AN/ALQ-135 internal ECM, AN/ALR-56C RWR, digital display instead of analog weapon selector, integration with AMRAAM, ALE-40/45 countermeasures dispenser.

It is also pre mid-2000s modernisation since it doesn't have AN/APG-63(v)1 simultaneous 6 targets engagement, Link16, JHMCS, AIM-9X integration, GPS navigation etc.

In short it's correct for ~1985-2000 scenarios - it doesn't have any capability 1985 MSIP II didn't already have.

But being FC3 module it's pointless to rivet count, something will always be wrong, many radar modes are missing even for 1979 basic F-15C like Velocity Search, Short Range Search, Low Pulse Repetition Frequency pulse backup mode, slewable AutoGuns, Super Search, Manual Track, Visual Identification, Beacon mode, Sniff passive listen-only mode, A-G Ground Mapping, A-G Plan Position Indicator for slant range, A-G HUD mode, AN/ALQ-128 EWWS and probably many other electronic gizmos.

Edited June 1, 2023 by bies

[GGTharos]

Every -34 I've read has 8 available TWS targets.  Even the old ones.  I'm not aware of any APG-63 version with TWS that had less than 8.

Edited May 31, 2023 by GGTharos

[draconus]

7 hours ago, bies said:

In manual its radar is named AN/APG-61(v)1

Nope, 61 was some mod of F-4 radar for Brits, please fix.

[Temetre]

Bit OT, but I find it interesting to hear the F-15 didnt have Datalink up to 2003. Since Link4 is only used by F-14 to show targets, that means our F-15 didnt have any of that wonderful radar datalink overlays? How does the earlier Aim-120 gets it mid-course updates?

I thought the Aim-120 was from the beginning using datalink to get mid course updates, like our C-5 variant that can get updates from the entire network. But clearly thats a later addition then. Anyone know how the Aim-120A/B got their mid course updates, was it just by radio signals by the firing aircraft, like with Aim-54s? I heard the brits originally got an 120A without the optional mid course correction feature, but that obviously sucked hard. Also makes me wonder how R-77 and PL-12 do this, assumed they also got a 120C style datalink control.

Edited June 1, 2023 by Temetre

[draconus]

17 minutes ago, Temetre said:

I thought the Aim-120 was from the beginning using datalink to get mid course updates, like our C-5 variant that can get updates from the entire network.

Where did you get such info. Imho you're mixing tactical datalink with radar<>missile datalink. Here's explanation:

The tactical datalink was tested before on small numbers of F-15C before afaik but they both were considered problematic at the time and/or not crucial.

[Temetre]

vor 31 Minuten schrieb draconus:

Where did you get such info. Imho you're mixing tactical datalink with radar<>missile datalink. Here's explanation:

The tactical datalink was tested before on small numbers of F-15C before afaik but they both were considered problematic at the time and/or not crucial.

Where did I get such info, have you seen how much conflicting information is out there?

So much bad info, terms like "datalink" can be very inaccurate, and the features/variants get constantly mixed up. Even sites like Wikipedia, who might not be accurate, but generally collect a ton of info, often got massive blindspots in areas like that. Even basic details like how mid-course guidance is sent isnt explained.

What you say/link helps a lot, thanks. So basically, the radar actually directly sends encoded control-signals to the missile, and if you lose a lock and the missile isnt tracking yet, then its just going by its own INS system? Then I suppose suppose the R77 and PL-12 (or so) work exactly the same as Aim-120C then, though maybe less sophisticated in hardware/software.

Aim-120D seems to be the exception, as in it being a two way datalink that actually uses Link-16 (tho C-7 also has some of that ability apparently).

 

One more thing, I assume when you lose and then reacquire the target signal, the Aim-120 gets updated again, and do you know if thats true for R-77/PL-12 as well? With semi-active missiles, I know the Sparrow can work on reacquired locks, but the R-27 ER is dead after a few seconds without guidance.

edit: Ohhhh that means semi-active missiles also get information from the radar, and only go passive in terminal phase or as backup (eg using planes flood horn)? That would explain a lot, I wondered how "passive radar" missiles could know range to enemy. Or Im wrong and they do it by the strength of passive radar returns... see thats why this stuff is confusing, nothing is quite explained^^

edit2: Nvm, Wikipedia is useful for once:

Zitat

The AIM-7P is similar in most ways to the M versions, and was primarily an upgrade for existing M-series missiles. Changes were mainly to the software, improving low-level performance. A follow-on Block II upgrade added a new rear receiver allowing the missile to receive mid-course correction from the launching aircraft. 

So the earlier Aim-7s either dont know range, or estimate it from radar returns.

Edited June 1, 2023 by Temetre

[draconus]

Since a lot of capabilities rely on specific missile versions I'll reply in general but it might not be a case for all of them.

ARH missiles usually go active when the tracking (and data commands) is lost and they have not yet reached the sufficient range. They search on their own while flying to the last intercept direction and might find the target there if lucky.

SARH missiles have to be directed by radar (be it STT, flood and data commands) from launch to a hit - they are passive only in the meaning that they don't emit signals themselves but the launching aircraft has to provide the signal and the missiles get directions by both reflected radar signals and data commands (when available). There were also some tests done ie. R-27P/EP for the real passive missiles that directed only onto the radar signals detected from the targets (fighters, AWACS) - not in service afaik.

There's also passive HOJ mode available to both types when the target is jamming and the missile can fly into the direction of jamming without any support from the launching aircraft.

[Temetre]

vor 2 Minuten schrieb draconus:

Since a lot of capabilities rely on specific missile versions I'll reply in general but it might not be a case for all of them.

ARH missiles usually go active when the tracking (and data commands) is lost and they have not yet reached the sufficient range. They search on their own while flying to the last intercept direction and might find the target there if lucky.

SARH missiles have to be directed by radar (be it STT, flood and data commands) from launch to a hit - they are passive only in the meaning that they don't emit signals themselves but the launching aircraft has to provide the signal and the missiles get directions by both reflected radar signals and data commands (when available). There were also some tests done ie. R-27P/EP for the real passive missiles that directed only onto the radar signals detected from the targets (fighters, AWACS) - not in service afaik.

Thx, I think I got it now.

vor 2 Minuten schrieb draconus:

There's also passive HOJ mode available to both types when the target is jamming and the missile can fly into the direction of jamming without any support from the launching aircraft.

Yeah, that one was really confusing to me! Thought there was some bug, till I learned most of the semi active missiles ingame have HOJ.

Edited June 1, 2023 by Temetre

[bies]

4 hours ago, draconus said:

Nope, 61 was some mod of F-4 radar for Brits, please fix.

Exactly, thanks for correction.

[GGTharos]

3 hours ago, Temetre said:

Bit OT, but I find it interesting to hear the F-15 didnt have Datalink up to 2003. Since Link4 is only used by F-14 to show targets, that means our F-15 didnt have any of that wonderful radar datalink overlays? How does the earlier Aim-120 gets it mid-course updates?

I thought the Aim-120 was from the beginning using datalink to get mid course updates, like our C-5 variant that can get updates from the entire network. But clearly thats a later addition then. Anyone know how the Aim-120A/B got their mid course updates, was it just by radio signals by the firing aircraft, like with Aim-54s? I heard the brits originally got an 120A without the optional mid course correction feature, but that obviously sucked hard. Also makes me wonder how R-77 and PL-12 do this, assumed they also got a 120C style datalink control.

 

The tactical DL has nothing to do with the missile DL.  That's why the missile DL originates from the shooter's aircraft, and cannot be guided by other aircraft.  The TDL is a completely separate radio equipment and software, the MDL is operated completely by the radar and emitted by the radar.

The Alaska eagles trialled DL terminals well before eagles overall got DL; it was too much and too soon, it turned out full JTIDS terminals could not operate on a fighter (at least at that time).

[GGTharos]

2 hours ago, Temetre said:

Aim-120D seems to be the exception, as in it being a two way datalink that actually uses Link-16 (tho C-7 also has some of that ability apparently).

Everyone keeps saying that.  'Citation please'.   Two-way DL doesn't mean anything in terms of which DL is used

 

2 hours ago, Temetre said:

One more thing, I assume when you lose and then reacquire the target signal, the Aim-120 gets updated again, and do you know if thats true for R-77/PL-12 as well? With semi-active missiles, I know the Sparrow can work on reacquired locks, but the R-27 ER is dead after a few seconds without guidance.

The MDL for 120 is transmitted for some 90 seconds, so it's available during that time.  For the R-27, it is transmitted up to a certain range, then replaced with the homing signal.  Once that happens, the DL does not come back.   For the sparrow, there's no DL at all, it's like an R-27 after the DL has lapsed.

2 hours ago, Temetre said:

edit: Ohhhh that means semi-active missiles also get information from the radar, and only go passive in terminal phase or as backup (eg using planes flood horn)? That would explain a lot, I wondered how "passive radar" missiles could know range to enemy. Or Im wrong and they do it by the strength of passive radar returns... see thats why this stuff is confusing, nothing is quite explained^^

Yeah you're wrong.  These missiles are a) tuned by the radar, b) receive pre-launch information and c) have receivers for the radar's emissions in the rear so at to use that as a benchmark for ranging, doppler shift etc.  AFAIK no one estimates range from radar returns as those can vary quite massively with even a small change in aircraft orientation.

Also, there's no real passive HoJ tracking.  This is a mis-reprentation - the missiles are tuned to and lock onto the radar's emissions.  They won't guide onto just anything ... so you have to keep illuminating the target so that it keeps repeating your radar's signal.  HoJ isn't some sort of stealth killer, otherwise why have a primary guidance mode anyway?   In almost cases the jammer should lower the Pk compared to a non-ECM environment.  It shouldn't allow you to turn around and let your missile continue guiding.

Edited June 1, 2023 by GGTharos

[henshao]

There were two trials with datalinked F-15s AFAIK; in the late 80s a handful of birds, and a full squadron of JTIDS aircraft (~20) at Mountain Home AFB in the mid 90s. The former didn't inspire much confidence but the latter inspired the installation of JTIDS on as many NATO fast movers as possible (eventually), though in cheaper/smaller terminals

[Temetre]

vor 48 Minuten schrieb GGTharos:

Everyone keeps saying that.  'Citation please'.   Two-way DL doesn't mean anything in terms of which DL is used

Hm, i cant remember seeing a specific quote for the Aim-120, thats true. I know the 120D (and IIRC C-7/8) listed enhanced off boresight capabilities, which would imo imply that theres more than just radar-guidance. 

Its definitely employed elsewhere, tho. Missiles like the newest Aim-9X blocks are claimed to use datalink to be controlled by other planes, thats part of the stuff about them being able to attack super high off bore (or even rearwise) targets. I know the Meteor is supposed to have that as well, and the Iris-T too.

But youre right, that doesnt mean the Aim-120D has datalink capability with other aircraft. And even if it was other aircraft, it does not specify if its the radar-datalink, or some Link 16 style system. And ofc then theres different 120D-blocks again.

vor 48 Minuten schrieb GGTharos:

The MDL for 120 is transmitted for some 90 seconds, so it's available during that time.  For the R-27, it is transmitted up to a certain range, then replaced with the homing signal.  Once that happens, the DL does not come back.   For the sparrow, there's no DL at all, it's like an R-27 after the DL has lapsed.

Thx I see, so its time limited, that makes sense. I suppose the missile+radar channels are tuned so DL data doesnt get confused?

Gotta re-read some stuff about the R-27R with that context in mind. Kinda impressive for such an old missile, considering the Sparrow lagged behind; but I guess Americans focused on active missiles. According to Wikipedia, the R-27 supposedly can be controlled by other aircraft or even retargeted; wonder if thats about mid-course control, but probably not in DCS implemented anyway.

As said tho, the Aim-7P Sparrow apparently got an antenna to receive datalink information as well. Thats the sparrows exception to the rule^^

vor 48 Minuten schrieb GGTharos:

Yeah you're wrong.  These missiles are a) tuned by the radar, b) receive pre-launch information and c) have receivers for the radar's emissions in the rear so at to use that as a benchmark for ranging, doppler shift etc.  AFAIK no one estimates range from radar returns as those can vary quite massively with even a small change in aircraft orientation.

Yeah thats basically my understanding of how those missiles worked. I suppose the pre-launch information already explains what confused me at first, thatll tell missiles how to initially manuever. Kinda like modern heatseekers.

And I wasnt aware that theres missile like R-27R (and Sparrow in Aim7P) that can get mid course correction data, just like modern active missiles.

vor 48 Minuten schrieb GGTharos:

Also, there's no real passive HoJ tracking.  This is a mis-reprentation - the missiles are tuned to and lock onto the radar's emissions.  They won't guide onto just anything ... so you have to keep illuminating the target so that it keeps repeating your radar's signal.  HoJ isn't some sort of stealth killer, otherwise why have a primary guidance mode anyway?   In almost cases the jammer should lower the Pk compared to a non-ECM environment.  It shouldn't allow you to turn around and let your missile continue guiding.

Oh I see, so the HOJ in DCS is completely unrealistic? Because from what Ive seen, it makes SARH missiless act like heatseekers

[GGTharos]

1 hour ago, Temetre said:

Hm, i cant remember seeing a specific quote for the Aim-120, thats true. I know the 120D (and IIRC C-7/8) listed enhanced off boresight capabilities, which would imo imply that theres more than just radar-guidance. 

Its definitely employed elsewhere, tho. Missiles like the newest Aim-9X blocks are claimed to use datalink to be controlled by other planes, thats part of the stuff about them being able to attack super high off bore (or even rearwise) targets. I know the Meteor is supposed to have that as well, and the Iris-T too.

None of this is well enough described.  There is a difference between actually being controlled by other aircraft, and using off-board (other aircraft's) data to guide your missile - you see where I'm going with that.   So you could in theory shoot at a DL target but the M-Link is still emitted from your aircraft.

1 hour ago, Temetre said:

But youre right, that doesnt mean the Aim-120D has datalink capability with other aircraft. And even if it was other aircraft, it does not specify if its the radar-datalink, or some Link 16 style system. And ofc then theres different 120D-blocks again.

Yep, that's the thing.

1 hour ago, Temetre said:

Thx I see, so its time limited, that makes sense. I suppose the missile+radar channels are tuned so DL data doesnt get confused?

Each missile is coded to a different ID for the DL onboard the aircraft and also separated in channels for the flight of 4 aircraft.

1 hour ago, Temetre said:

Gotta re-read some stuff about the R-27R with that context in mind. Kinda impressive for such an old missile, considering the Sparrow lagged behind; but I guess Americans focused on active missiles. According to Wikipedia, the R-27 supposedly can be controlled by other aircraft or even retargeted; wonder if thats about mid-course control, but probably not in DCS implemented anyway.

The sparrow had other advantages ... basically better overall electronics.  You'll see on the eagle VSD and other radar displays a little circle on the DLZ called the 'DSR cue' when the sparrow is selected.  This is the computer's guess as to how far it believes the sparrow seeker can see a reflection from your radar based on the selected target.  Do not shoot if the target is beyond the DSR cue    The sparrow will launch and immediately attempt to lock onto the target.   The R-27 will behave the same way if the range to target is short enough - straight to guidance signal, no DL.

R-27's cannot be controlled by other aircraft, despite interesting stories to the opposite.  TO be more precise though ... yes, 'sure they can be' but then you have two radars tuned to the same channel, which means they cannot both operate on targets close to each other at the same time.   And close isn't all that close ... why?  They'll jam each other and each other's missiles.   So basically you can expect radar channels and missile guidance channels to be set apart for each aircraft in the flight.   Same applies for sparrows, and failure to implement this (a lesson hard learned) led to some spectacular misses and premature warhead detonations.

 

1 hour ago, Temetre said:

As said tho, the Aim-7P Sparrow apparently got an antenna to receive datalink information as well. Thats the sparrows exception to the rule^^

It means you can shoot beyond the DSR cue

1 hour ago, Temetre said:

Yeah thats basically my understanding of how those missiles worked. I suppose the pre-launch information already explains what confused me at first, thatll tell missiles how to initially manuever. Kinda like modern heatseekers.

If you mean LOAL yes, but heat seekers are very typically LOBL so that's a huge difference.   

1 hour ago, Temetre said:

And I wasnt aware that theres missile like R-27R (and Sparrow in Aim7P) that can get mid course correction data, just like modern active missiles.

Oh I see, so the HOJ in DCS is completely unrealistic? Because from what Ive seen, it makes SARH missiless act like heatseekers

Well, think about it this way ... why have a jammer if all it does is hurt you?  So you have two kinds of jammers, broadly speaking:

1) Self protection jammers, used by fighters, bombers (bombers have far more bombastic jammers though that can act like the ones below) etc

2) Stand-off jammers which operate almost contantly to end enemy communications and raise the noise floor of air defenses to allow own side to sneak closer

Your missile's and radar's HoJ modes deals with 1 above.  That type of jammer will attempt to repeat the radar's signal in a way that breaks the lock or otherwise sends the missile somewhere else.   The key here is that it's repeating the signal that the missile is trying to home onto.  Break the lock and the jammer stops repeating (within a  few seconds) and there's nothing for the missile to home onto.  In DCS the 'jammer' is just a flag that doesn't take this into account, so it makes the missile act like a heat seeker.

The SPJ should be able to lower pk on average, but also possibly completely trash the missile or in rare circumstances, make everything worse for the defender.   We generally wouldn't be concerned with the extreme cases in a game IMHO.

The SoJ described in 2 above requires something like an ARM or other specialized missile - these are the 'anti-radion AAMs' you normally hear about.  It's not 'mere HoJ' although the possibility to pull that off may exist...but if it does, it's locked up in manuals we have no access to so unless proven otherwise I'd lean on the 'can't do this' side for HoJ .    Also, while specialized missile guidance exists to tackle SoJs, typically you send in a good old SAM or AAM anyway.

[henshao]

This was from a multiservice public release in 2000: