F-15C avionics wishlist

[SwingKid]

Hello all,

 

I am doing some research of real-world and Lock On F-15C avionics.

 

While I don't work for ED and there can be no specific promises or commitments, the Russian avionics improvements in v1.1 "Flaming Cliffs" for Su-27 and MiG-29 aircraft shows that sometimes it's possible for new features to be implemented.

 

As such, I am interested to know your suggestions and thoughts, how the F-15C avionics can be improved. I will try to organize the suggestions into an ordered list for ED to consider, and also to provide feedback based on my research of the real-world systems accumulated so far.

 

Since this has the potential to become a long and involved discussion, I decided to separate it from the main "v1.1 features" discussion into its own thread.

 

Here is the list as I have arranged it myself so far. I will be editing this list directly in the first message of this thread to keep it up to date as new ideas and suggestions come up.

 

Ideas to date (07/12/2004 - need to be re-ordered):

1. To fix the code and separate the HSI nav system from the combat modes on all aircraft (not just F-15), so that the HSI continues to show the NAV information about the next waypoint even when the radar or other systems are being used against a target.

2. To implement a finite angular and range resolution for all radars, so that closely spaced targets at a distance appear on the display as a single target.

3. To use time-limited "legacy" tracks, so that targets leaving the TWS scan zone, or returning from STT to TWS, not all tracks are immediately lost.

4. To review the operation of the TWS mode, and ensure that it is not going into STT incorrectly when a target is designated (needs further discussion, especially regarding ECM targets).

5. To ensure RWR is working correctly (needs further investigation, especially regarding accurate symbology).

6. To allow the AIM-120 Rmax zone to expand if the F-15C pitches upwards at the moment of launch, to represent pilot-assisted "lofted" launch trajectory.

7. To implement the "Sort" ("Expand"?) submode, which zooms in the radar display to help "break-out" closely spaced targets.

8. To replace the existing "burn-through" model with a "kinematic ranging" AOJ submode, for estimating the range to an ECM target.

9. To introduce a fighter datalink display on the MPCD (needs further investigation, which F-15Cs actually have such feature).

10. To introduce an air-to-ground radar mode.

11. To let chaff be more effective when rearwards-facing ECM is used.

12. To introduce the "passive Sniff" mode.

13. To let the pilot manually "interrogate" IFF.

14. To review the close-combat auto-acquisition modes (include SuperSearch and ensure correct lock-on range).

15. To introduce the Python and other Israeli weapons.

16. To add color to MPCD display.

17. To introduce night vision goggles (NVGs).

18. To let a single ECM aircraft cover other targets near the same bearing

19. To expand TWS mode with (N)DTWS and HD(ND)TWS

20. To include low-altitude, Med-PRF clutter on the radar display

21. To include Vector and Range Gated High (RGH) search modes

22. To include the "miniraster" function while locking a target

23. To make the arrestor hook functional

24. To ensure the "automatic trimmer" is working correctly

25. Default Master Arm switch to off during ramp start.

26. Add ADI and VI master modes

27. Research the Israeli helmet-mounted sight

28. Collimated HUD display that moves with pilot head, as in Il-2

29. Correctly scaled HUD wrt other instruments

30. "Data fusion" model for use with datalink - AWACS has limited detection range

31. Check for any radar gimbal limits in roll during scan and TWS mode, as on Su-27

32. Check to ensure gunsight radar lock is not being lost at close ranges or in vertical flight without reason

33. Check to see if lock is lost in co-speed tailchases in real life

 

Thanks for your interest,

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[SwingKid]

Re: F-15C avionics wishlist

 

Teleported from the "v1.1 features" discussion:

 

Yes, if the bandit has his ECM on, even after burn-through, the 15's TWS mode radar can only get an STT lock on him. It's been discussed and pretty much ended looking like it has been incorrectly modeled in LOMAC. But, personally, I'd like to hear ED's version of whether or not this should be so.

 

If I understand correctly, then in real life there is (a) no burn-through against a self-protection jammer, and so (b) no TWS vs an ECM target. The only way to lock an ECM target is real life is by angle-on-jam, which can't be used in TWS because it requires the monopulse radar antenna to stay pointed at the target.

 

From what I can tell, ED decided to relax (a) because of the great user outcry about burn-through, but kept (b) faithful. The result is that it looks weird, because after burn-through you can see the ECM target as a normal target on your TWS scope, but to engage it you have to go to STT (instead of HOJ).

 

Ideas?

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[S77th-GOYA]

I would like to see full realism modeled into LOMAC. If that means no burn through on self-jamming bandits, so be it. Tactics will change to fit the real parameters.

[D-Scythe]

On the assumption that the F-15 radar is of the MSIP type (meaning the AN/APG-70) because it a) supports AMRAAM and b) has NCTR, I think that the range of the AACQ modes should be extended to 15 nm, as is standard in all F-15 radars beyond the F-15A's AN/APG-63.

[GGTharos]

SwingKid, those are great and reflect my views of what should be done and investigated.

 

Some comments:

 

1) Absolutely.

 

2) You rock, I always wanted to see this.

 

3) Also TWS should track all targets, or attempt to, including the ones that elave the scan zone. (Not counting targets that were not tracked before, of course, unless they get close to one of the targets being tracked - this is why TWS takes so long to update the display, ebcause it tries to do all this tracking)

 

4,5,6,7,8,11 nice ideas ...

 

9) ... this is fairly recent I believe and most F-15C's don't have it even now.

 

10) A -little- iffy, but might be nice, esp. for the IAF F-15 which does have it. In this case, Python-4 and helmet sight/hud for that aircraft may also be nice, but I'm startin got hink that this would require two different F-15 models.

 

 

Back to 3). As I udnerstand it the SPJ will deny range completely only until 'burn through'. What happens at 'burn through' is that you can now get a somewhat reliable but not accurate vector, and range, and you can track, but it might cause strange things to appear on your radar screen (the doppler return could be way off for example and it would show you the wrong speed) ... however, statistical tracking could aid in determining the bandit's true vector, however, ithis depends on the radar 'guessing' where the enemy is going to be next and if the enemy changes direction the radar will have to work harder and longer to find it. It could make some specific assumptions about where to look like 'how far in each direction could it have gone since I last looked at it given 600kts of speed?) and look in an area like this to find it again, but then if it doesn't find it, for any reason, you lose the trackfile.

 

Anyway, I heard things that imply all this from a real pilot, but this was hearsay and I encourage you to continue your investigation to find out with more certainty.

[D-Scythe]

 

9) ... this is fairly recent I believe and most F-15C's don't have it even now.

 

 

Wrong. Currently, more than half of all F-15s, including ANG F-15A/Bs, should have MID/FDL, and all F-15E's.

 

 

Back to 3). As I udnerstand it the SPJ will deny range completely only until 'burn through'. What happens at 'burn through' is that you can now get a somewhat reliable but not accurate vector, and range, and you can track, but it might cause strange things to appear on your radar screen (the doppler return could be way off for example and it would show you the wrong speed) ... however, statistical tracking could aid in determining the bandit's true vector, however, ithis depends on the radar 'guessing' where the enemy is going to be next and if the enemy changes direction the radar will have to work harder and longer to find it. It could make some specific assumptions about where to look like 'how far in each direction could it have gone since I last looked at it given 600kts of speed?) and look in an area like this to find it again, but then if it doesn't find it, for any reason, you lose the trackfile.

 

Anyway, I heard things that imply all this from a real pilot, but this was hearsay and I encourage you to continue your investigation to find out with more certainty.

 

I also encourage you to search for more information. E-mail a respected F-15 expert like Steve Davies, perhaps? Anyway, from what I understand, burning through an enemy's SPJ is not the only way to counter ECM; AFAIK there are several other ECCMs built into the F-15C's radar to help it track a target even before it burns through.

[Shepski]

Great thread Andrew!

 

I think what Eagle needs to do is chose a radar version and model it's features rather then features from different models as we now have.

 

I think the features that would be found in typical F-15C of the late 1980's and 90's is the MSIP II version with the Hughes AN/APG-63(v1). The AN/APG-70 was first used in the MSIP II upgrade but was subsequently replaced with the APG-63(v1) which is what the majority of F-15C's now have.

 

The improved features of the APG-63(v1) over the APG-63 are:

 

*better capability to track multiple targets and to find targets at low altitude(better ground clutter filtering).

*Raid Assesment mode(RAM) - for breaking out of closely grouped targets.

*AACQ mode radar lock on range of 15nm.

*Full color MPCD.

*JTIDS and data-link capability.

*Improved TEWS suite.

 

The above would be the main new features but there also needs to be more functionality added to what we have in Lock On now like:

 

*adjustable bar scan.

*slewable TWS azimuth zone.

*Super Search AACQ mode - 30x20 radar scan pattern, I think, but it basically scans within the dimensions of the HUD.

*radar stand by mode.

 

Cheers

[AMVI_Bad Boy]

I would like to see full realism modeled into LOMAC. If that means no burn through on self-jamming bandits, so be it. Tactics will change to fit the real parameters.

 

I agree totally!

 

 

I think the features that would be found in typical F-15C of the late 1980's and 90's

 

In that year USAF have a NVG also...(expecially for the A-10).

 

 

Thanks for yours effort!

[SwingKid]

I would like to see full realism modeled into LOMAC. If that means no burn through on self-jamming bandits, so be it. Tactics will change to fit the real parameters.

 

I think the burn-through was retained as a compromise, since the "kinematic ranging" method to determine target range is absent. Maybe the burn-through feature should be removed only after kinematic ranging is modelled?

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[SwingKid]

10) A -little- iffy, but might be nice, esp. for the IAF F-15 which does have it. In this case, Python-4 and helmet sight/hud for that aircraft may also be nice, but I'm startin got hink that this would require two different F-15 models.

 

I guess it would be low priority since its role is air-to-air, but AFAIK the APG-63, -70 and -63(v)1 all have air-to-ground mapping modes available.

 

Back to 3). As I udnerstand it the SPJ will deny range completely only until 'burn through'.

 

My trouble was to calculate the burn-through range. I kept getting ridiculously low values. Then I went to a radar textbook and it appeared to confirm my finding:

 

 

:?:

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[169th_DedCat]

Great stuff guys. I'm glad to see I'm far from being the only one who thinks the F-15 needs some tweaking.

 

http://forum.lockon.ru/viewtopic.php?t=2192

 

I'm a big advocate for having all the jets as finely detailed as possible. The Russian jets look great in 1.1, but the F-15 needs some improvement.

[SwingKid]

I also encourage you to search for more information. E-mail a respected F-15 expert like Steve Davies, perhaps?

 

Good lead. Steve Davies, Gene Buckle and the entire community at http://www.f-15estrikeeagle.com and http://www.f15sim.com have been and continue to be a tremendous help. :) Very interesting sites, highly recommended.

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[SwingKid]

*Raid Assesment mode(RAM) - for breaking out of closely grouped targets.

 

Latest word from the pilots is that RAM has been made obsolete by some TWS options and removed.

 

I added some of your other suggestions to the list but not the "stand by" mode - Wouldn't this be indistinguishable to the sim pilot from "off"?

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[169th_DedCat]

...the "stand by" mode - Wouldn't this be indistinguishable to the sim pilot from "off"?

 

I believe a radar in sniffed stand-by mode would still receive information from the JTIDS link and any transmitting jammers, while an off radar would not. This seems like a pretty minor detail and a low priority to me though.

[Shepski]

Andrew... I would change #16 to read...

 

Replace the current PACS with a MPCD.

[SwingKid]

Andrew... I would change #16 to read...

 

Replace the current PACS with a MPCD.

 

Hmm.. We should keep the word "color" somewhere, so that the meaning is not difficult for Russian readers.

 

Or, did you mean to add the self-test BIT pages?

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[Shepski]

Andrew... I would change #16 to read...

 

Replace the current PACS with a MPCD.

 

Hmm.. We should keep the word "color" somewhere, so that the meaning is not difficult for Russian readers.

 

Or, did you mean to add the self-test BIT pages?

 

The PACS and the MPCD are 2 different animals AFAIK. The PACS is on older model Eagles.

 

Multi Purpose Color Display is maybe how we should phrase it?

[SwingKid]

AFAIK, the MPCD has a "PACS" page (displayed in Lock On), a BIT page (not in Lock On), and a couple of others that I think are used for pre-flight programming.

 

The original PACS didn't look like an MFD at all, but rather more like the A-10A armament control panel with mechanical switches. You can see it here:

 

http://deltasoft.fife.wa.us/cockpit.htm

 

The MPCD should technically be "color" but I'm not sure about "full color." I've only heard of it displaying yellow, green, cyan, blue and white - no red.

 

-SK

 

Lock On v1.1 "Flaming Cliffs" beta tester

[Shepski]

Ok I see what you mean.

 

:)

[Wags]

This is a good start Andrew. Here are some APG-70 specific features I’d love to see someday:

 

Master mode selections of:

A/A Mode

A/G Mode

ADI Mode

VI Mode. Once a target is locked, the ASE circle and dot will provide steering data to bring the aircraft directly behind the target

 

A/A Attack Mode Selection, weapon select. This is a three position select switch on the throttle that enables GUN, SRM, or MRM

 

A functional mater arm

 

Elevation bar scan selection of 1, 2, 4, 6, and 8

 

Frame store selections of 0, 1, 2, and 3

 

All standard radar search modes including:

1- MED: MPRF for search and TWS for 10, 20, 40, and 80 range scales.

 

2- INLV: MPRF and HPRF for 20, 40, and 80 range scales. Alternating INLV or HPRF scans at 160 and MPRF only at 10.

 

3- HI: HPRF at all range scales and search and TWS modes.

 

4- VCTR: Velocity search between 80 and 2,400 kts relative

 

5- RGH: Uses an intermediate PRF between MPRF and HPRF that gives good all-aspect acq. The 10 -20 nm scale uses a short pulse wave form to provide better break out sensitivity. Not to be uused below 6,000 AGL

 

Auto Acq. Modes:

1- Boresight

2- Long Range Boresight

3- Supersearch

4- Vertical Scan

5- Gun Scan

 

All TWS Modes:

1- NDTWS

2- DTWS

3- HDTWS

4- NDHDTWS

 

NCTR interrogate (coolie switch inboard)

 

Additional MPCD functionality:

1- Combat jettison

2- JTIDS display (SIT), functions including:

Auto-range (tied to VSD range)

PDT lock/launch line

Altitude and radar coverage lines

Reference lines and area symbols

Waypoint and route symbols

Ownship weapon inventory

Declutter

Friendlies

Data

Strength/type

H SAM

Ship

Radar coverage

Routes

Lines

4- A/A and A/G PACS select (FYI. PACS is one portion of the MPCD functionality)

5- MRM target size select

6- Flight member ID input (for deconflict)

7- Color indications for weapon status

Green = ready

Amber = failed / hung

White = stand by

8- COOL switch set to on when master arm activated

9- A/G weapon video display

10- AIM-9 self-track toggle

 

Cycle through TWS targets in priority list by range to be PDT when tapped less than one second. When held more than one second, nearest track is set to PDT (coolie up)

 

TWS undesignated target (aft on boat switch)

 

Weapon reject cycle option. When selecting MRM (AIM-120 / AIM-7), missile reject is used to cycle between types

 

When TDC is pressed for less than one second, radar antenna should be slaved to TDC azimuth position. Hold TDC more than one second command SORT mode that includes 30-degree azimuth that is heading stabilized.

 

On HUD, cue for AIM-120 selected is “A(number of type remaining)C”, AIM-7 is “M(number of type remaining)M”, and AIM-9M is “S(number of type remaining)M”

 

If missile type onboard that is not in priority is also between Rmin and Rtr, that weapon cue (S4M for example) will flash next to the current weapon in priority

 

With MRM selected, the selected target size (from the PACS) should be displayed on the HUD unless set to Normal.

 

When an MRM is launched, the current present position and time of day are displayed on the HUD

 

Track memory (MEM) mode should have the TD box flash on the HUD when the radar has lost lock but is still trying to reacquire

 

SNIFF special mode indicators should be on HUD when appropriate

 

JAM, HOJ, AOJ should be moved to the top of the lower right data block on the HUD

 

If more than one missile is in air at the same time, the TOF for the minimum and maximum times are displayed on the HUD.

 

An Enhanced Identification (EID) box cue should flash in the TD box when the target has been interrogated to be a friendly

 

Along the bottom of the VSD, the magnetic bearing and range to bull’s eye is displayed when in search and TWS modes. When in STT, the magnetic bearning and range between bulls and target is displayed.

 

Along the right outer side of the VSD, the aircraft’s present lat/long position is displayed.

 

In addition to the current GDS gunsight, provide LCOS version as well

 

Include the Ropt cue on the VSD

 

TWS scan should center on PDT

 

TWS modes should be inhibited when in guns mode

 

MAR bar on the missile fly-out line

 

Hot and Cold hit icons when in a LRS mode

 

Add Expanded Azimuth Display. This is enabled when in STT and the target is more than 45-degrees off in azimuth. When this happens, the azimuth is increased to +/-75 degrees and the outter grid line represents break-lock point.

[GGTharos]

:shock:

 

Wags, could you epxlaid what each SNIFF mode does, what each TWS mode does, and these two:

 

5- MRM target size select

6- Flight member ID input (for deconflict)

 

I suspect 5 is a means of choosing which retur size target the missile go after if it detects multiple, so you could for example, have it hit bombers instead of fighters when firing on a formation.

[169th_Cobra]

My personal opinion is that lomac has a great balance of enough imersion with out going full-blown realism ala Falcon4 and all its patches.

 

The one thing i truely enjoy about lock-on is its (relative) simplicity.

 

Personally i would only want to see the F15 avionics reach a similar level where the russian avionics will be in 1.1 and then leave it at that. I would rather see other areas of the game improved before the radar gets a whole heap of new modes to try and get my head around.

 

How about the fuel flow indicator? I for the life of me cant figure it out. Full burners it reads 100 units and idle it reads 90 units from memory. Go figure.

[Wags]

SNIFF mode in general is a receive only (standby) mode used to detect jamming of the radar channels or to provide a minimum radar radiation time to prevent detection. Targets that are jamming the radar are received as the antenna sweeps past their position.

 

DTWS = Designated TWS (normally entered from STT, HOJ, or NDTWS / HDTWS)

 

NDTWS = Non-Designated TWS (entered by TDC designating VSD or using undesignated boat switch function).

 

HDTWS = High Data rate TWS (faster track updates). Entered like DTWS but can cycle between DTWS and HDTWS with auto-acq switch forward

 

NDHDTWS = Non-Designated, High Data rate TWS. Entered like NDTWS, but can cycle between the two with the forward auto-acq switch.

 

The MRM target size selection influences the AIM-7 Dynamic Seeker Range (DSR) and the AIM-120 Missile Active Range (MAR) calculations.

 

Regarding flight member ID, this ID is important in the real world to prevent missile-to-missile mutual interference (MI) between AIM-120s launched among aircraft in the same flight.

 

 

 

:shock:

 

Wags, could you epxlaid what each SNIFF mode does, what each TWS mode does, and these two:

 

5- MRM target size select

6- Flight member ID input (for deconflict)

 

I suspect 5 is a means of choosing which retur size target the missile go after if it detects multiple, so you could for example, have it hit bombers instead of fighters when firing on a formation.

[GGTharos]

So if you enter the same ID, you could guide someone's missiles if they fired them? Ie. the datalink would be to your aircraft if they kept their radar off?

 

Also, I don't really understand the difference between the TWS modes ... does Designated eman that a target has been bugged?

[olaleier]

Now THAT is a wishlist Wags. :shock:

 

Btw, nice to see you on Lock On forums again, hope the new projects are treating you nicely. :D