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Saab 37 Viggen

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Re: Saab 37 Viggen

Postby Octal450 » Thu Sep 10, 2020 11:04 pm

Fantastic thank you Colin

Kind Regard
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Re: Saab 37 Viggen

Postby colin_geniet » Sat Jan 09, 2021 7:07 pm

Version 5.0.0 has been pushed to FGAddon, and this is a very big update, if I may say so myself!
Here's the list of major changes. See below for details.
  • Added a flight manual
  • Removed the AJ 37 variant
  • Reworked the front instrument panel
  • Rework of the HUD and MI display for the JA variant
  • Completely new HUD for the AJS variant
  • Added main mode selector knob to the AJS variant
  • Added an IFF system, and for the JA variant a fighter link
  • New MP damage system, using the Emesary notification framework
  • Significant changes to fire control systems
Complete list of changes is here: https://raw.githubusercontent.com/Nikol ... ngelog.txt

Minimum supported FG version is now 2020.3.1


Flight Manual
At long last there is a flight manual, created with the help of Rick Gruber-Riemer!
You can find it in the aircraft directory under 'JA37/Doc/', or here: https://github.com/NikolaiVChr/flightge ... t/JA37/Doc. In simulator, the menu 'JA 37 > Manual' can be used to open it. Should anyone be interested, source code is here: https://github.com/NikolaiVChr/flightge ... umentation
The manual is very far from complete, but should already contain some useful information, notably regarding the new changes. In particular you should refer to it regarding the new AJS HUD, and the changes to controls and keybindings.


New HUD
The HUD has been rewritten for both the JA and the AJS.
The JA HUD hasn't changed much (the previous one was already very accurate), except for combat-related stuff - more details below.
On the other hand, the AJS HUD is completely new, and quite different from the JA HUD. I very strongly recommend checking the dedicated chapter in the manual, since the AJS HUD is nothing like the usuals modern HUDs, and it is not easy to figure out what is displayed.
Image

AJS main mode selector knob
This is one of the most important knobs on the AJS! It is on the radar control panel, just next to the throttle. It selects the aircraft mode, among Self test, Standby, Navigation, Combat, Reconnaissance, Instruments landing, and Optical landing. (test and reconnaissance being unimplemented). Keybindings 'm/M' can be used to rotate the knob.
The keybindings 'Y' (landing mode) and 'h' (combat mode) have been removed.
Image

New MI display
The MI (radar screen for the JA variant) has been reworked. It is now a B-scope (shows azimuth and range of radar echoes). Symbology has been improved based on photos and pictures of the real MI.
Controls have also changed a bit: keybinding 'n' (cycle radar echoes) has been removed, as it is particularly unrealistic. Tracking a radar echo is done by moving the MI cursor onto that echo, and clicking.
There are a number of ways to control the cursor:
  • Add joystick keybindings, either through the GUI, or by binding properties '/controls/displays/cursor-{slew-x,slew-y,click}'
  • Press 'y' to control the cursor with flight controls, press 'l' to click. Pressing the trigger to click no longer works
  • [NEW] Enable the option 'arrow keys control cursor' in the Viggen options dialog, and use arrow keys to move the cursor, 'enter' to click.
See the manual for more details.
Image

Regarding the AJS radar
It is no longer possible to lock onto a target with the radar - this is just no how the AJS radar works. And the new AJS HUD won't display any such thing, so locking on a target would be next to useless anyway. The AJS radar still works: it shows the bearing and range of any radar echo in range. But it's up to you to make use of this information (admittedly, it is currently very underwhelming, and I hope to improve it soon).

IFF
IFF allows allied aircrafts to recognize each other. The control panel is on the rear right panel. There's a power knob (OFF/AUTO/ON), and a channel selector knob (it goes up to 11!).
Image
An aircraft tracked on radar will be recognized as friendly if its IFF is on and set to the same channel as yours. It will then be displayed with a cross on the MI and the HUD, and in green on the TI (anything else is red). In addition, ctrl-F will interrogate the contact under the MI cursor, and display a cross over it on the MI if it is friendly. The dialog 'Friends (IFF)' works as a whitelist for IFF: any callsign entered will be reported as friendly, regardless of IFF code.
The AJS variant only has the transponder part of the IFF system (it can be identified by others, but not identify them).

Fighter Link
Fighter link allows to share data between aircrafts in a same flight, e.g. their position, or the position of tracked radar contacts. Together with fighter control (similar, but between aircraft and ground command center), it was one of the most innovative features of the Viggen fighter variant.
Fighter link is turned on with the SYST>DL menu on the TI display (HSD). When it is on, the small 'DL' box on the lower left of the TI is green. The fighter link channel selector is just in front of the comm radio. To input a channel, press 'DEL' (clears the field), then use the comm radio numpad to enter the channel.
Image
Viggens on the same fighter link channel will share their own position, and the position of any radar contact they are tracking. All of this is then displayed on the TI display.
However, the TI display no longer shows all radar echoes in range (only the tracked one), as this was quite unrealistic, and somewhat defeats the point of fighter link.


Multiplayer damage using Emesary
This is a completely new multiplayer damage system, developed by Nikolai V. Chr. and Richard Harrison using the Emesary notifications multiplayer bridge.
What it means in practice:
  • The automated chat messages are completely gone. Civilian pilots will enjoy not being annoyed by these messages (particularly from the less polite of fighter pilots, ahem). Military pilots will enjoy the added realism.
  • Some new features have also been added: flares, missile trails, ejection seats are displayed over MP, and missile warnings are received on the RWR. Of course, this is only enabled if both sides toggle MP damage on.
  • Finally, all of this is completely incompatible with the old MP chat damage system.
Please note that it requires FG 2020.3.1 or later to work

Fire Control Systems
Weapon controls have changed significantly.
  • There is now a trigger safety. Its role is complex, as it also arms the selected weapon when moved to the unsafe position. Because of this, proper use of trigger safety is not obvious, and is required to use weapons.
    The general procedure is
    1. Select the desired weapon, and enter combat mode if desired.
    2. Only after that open the trigger safety (shift-E), normally once the target is in sight/on radar, and you have decided to shoot.
    3. Fire. For missiles, fire only one weapon - the next ones won't work anyway.
    4. Secure the trigger, repeat procedure if necessary.
    See the manual (last chapter) for more details.
  • Master arm is gone - there is no such thing in the Viggen
  • Combat mode (which used to be controlled by master arm) is no longer required to use weapons. It still exists, but only to provide additional aiming information. In the JA 37, combat mode is enabled with 'h' (which used to be master arm). In the AJS 37, it is enabled with the main mode selector knob (see above).
  • Some keybindings (e.g. for weapon selection) have changed, see the in-simulator help menu, or the manual.
  • For the AJS 37 only: since it is no longer possible to lock on a radar contact (see above), all weapons have been adapted to allow firing them without lock. Most weapons now have realistic behaviors; a few, not quite so...
    • For IR A/A missiles (sidewinders): the seeker head is locked straight ahead. You must lock by steering the aircraft towards the target. Once a lock is obtained (sidewinder sound changes), you can uncage the seeker with 'U' to allow it to follow the target. Press and hold 'U' to reset the seeker.
    • For the Rb 04 and Rb 15 A/S missiles, and the m/90: just fire them towards the target, and they will lock on the first thing they find (for the Rb 04 and Rb 15, this is mostly accurate, although the target search logic should be far more complicated. For the m/90, this is complete nonsense since it should use inertial guidance towards a preset target waypoint).
    • For the Rb 75 Maverick: the seeker position is displayed on the HUD as a small circle. It is manually controlled using the cursor controls (see above in the MI display section). Once it is over the target, click to lock on the target.
      (In the real Viggen, the small EP-13 screen is used instead to display the Rb 75 TV seeker image. Other than that, the controls are somewhat accurate).



Read the manual, enjoy your flight, and report the bugs!
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Re: Saab 37 Viggen

Postby Johan G » Sat Jan 09, 2021 10:42 pm

I highly recommend trying out this aircraft, it is quite fun to fly.
Low-level flying — It's all fun and games till someone looses an engine. (Paraphrased from a YouTube video)
Improving the Dassault Mirage F1 (Wiki, Forum, GitLab. Work in slow progress)
Some YouTube videos
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Re: Saab 37 Viggen

Postby colin_geniet » Sat Apr 24, 2021 7:57 pm

Maybe it would be a good idea if I did more in this topic than post a big changelog every 6 months or so :roll:. So here's a summary of what has been added to the development branch (https://github.com/NikolaiVChr/flightgear-saab-ja-37-viggen/), and I'll try to do it more regularly in the future!

Lights
First, for anyone on FG next branch can now enjoy compositor clustered lights:
Image
Most useful are the landing and taxi light, but nav lights and beacons are also there for eyecandy.

Brakes
The brake system has been improved a bit. The hydraulic accumulator is implemented, so that brakes can still be used in case of hydraulics failure, although only a few times.
Parking brakes controls are more accurate: one presses the brakes fully, then pulls the parking brake handle to lock them. Unlocking is done by pressing the brakes again.
And there are chocks:
Image

Right wall
The right side of the cockpit got a small rework. Two important additions: the JA now has a clock/chronometer, and the AJS has a new weapon panel (which I need to finish implementing!).
Beside that several objects have been moved to their correct place, and some resized.
Here's how it looks for the JA (clock on the very left) and AJS (weapon panel in the upper middle, with the two big knobs):
Image Image

Fuel and Payload dialog
I had some fun with this dialog: I merged the FG standard 'Fuel and Payload' dialog with the custom Viggen 'Loadout' dialog, and added a canvas payload preview.
Image

Ground crew panel (AJS only)
This is a new Canvas dialog which represents a part of the ground crew panel. Its primary purpose is to inform the computer of which weapons have been loaded. If this is not incorrectly set, weapons won't work at all.

The good news: you don't actually have to do it: there is an option to have the ground crew do its job, and it is on by default. However, this only works if your loadout is valid, and the AJS is very picky regarding which loadouts are valid! The general rule is: only one type of weapon is allowed (not counting sidewinders), with two exceptions: AKAN + Rb 05, or AKAN + Rb 75. If you don't respect these rules, the ground crew will make sure to remind you, by shouting at you (in red) :mrgreen: .

Finally, there are two interesting settings which can only be modified through this panel: the upper position of the foreplane flaps (-4deg or -7deg), used to trim rear-heavy loadouts, and the safety distance for aiming.
Image


Coming soon™
I started reworking all the comm radios (not least of which because we can now use them on MP thanks to the awesome FGcom-mumble). You can expect to see the historical range of VHF frequencies (103-160MHz) plus UHF, as well as a way to load and use the ca. 1000 preset channels which the Viggen can use.

valtsu41 started re-texturing the warning panels, so you can expect 1. Swedish warnings, as alternative to the English ones; 2. the AJS version of the panels, which is somewhat different; and 3. fixes for a number inaccuracies.
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Re: Saab 37 Viggen

Postby Octal450 » Sun Apr 25, 2021 4:18 pm

Colin, thanks alot for your work. It's much appreciated!

Kind Regards,
Josh
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Re: Saab 37 Viggen

Postby budyboy12 » Fri May 14, 2021 3:20 am

how do you use the radar and the radar guided missiles. they make no cence and all the wiki and videos say is with the old cockpit
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Re: Saab 37 Viggen

Postby colin_geniet » Fri May 14, 2021 7:59 am

budyboy12 wrote in Fri May 14, 2021 3:20 am:how do you use the radar and the radar guided missiles

I assume you are talking about the JA 37 variant, and using the Viggen version 5.0.0. (Please indicate these when asking this kind of question).

For the radar, you need to use the cursor on the MI (center screen) to select an aircraft. There are several ways to control the cursor, they are described in manual section 5.1.1 (Radar Stick Controls).
For missile, the usage procedure is described in chapter 7 on the manual (Weapons operation). I would guess that your issue is with the trigger safety (keybinding shift+E).
If you're looking for the manual, it is in Aircraft/JA37/Doc/ in the aircraft directory, and there is a menu (JA 37 > Manual) to open in from FlightGear.

I will point out that all of this was written in the v5.0.0 release announcement post, 5 posts above :wink:.
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Re: Saab 37 Viggen

Postby idw » Tue Jul 13, 2021 8:28 pm

Hi,
firstly I want to thank you for your hard work, Viggen is by far my favorite aircraft to fly!
I'm playing around with multiscreen settings and then I notice this strange rendering:

Image

Setup used:
-GPU: AMD Radeon RX460
-one virtual screen (Eyefinity) over two monitors
-xml settings: 1 window (3840*1080), 1 view, 1 camera
-JA37 version: 5.0.0

Observations:
-this happens in all views (cockpit, tower,...) in FlightGear 2020.3.9 and 2020.4
-note that the smoke trail is rendered even in the black area
-all others aircrafts (default Cessna, various hangar ones) are fine (no black area)
-FPS is good (around 20-25, like with mono screen setup)
-this doesn't happen with a 2 windows, 2 views, 2 cameras xml setup (but FPS drops to 10)

So, I don't know if this is an issue or a bad config.
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Re: Saab 37 Viggen

Postby Necolatis » Tue Jul 13, 2021 9:08 pm

Its the blackout effect, its really made for 16:9 monitors. So since you have a wider setup, you will see those black bands.
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Re: Saab 37 Viggen

Postby colin_geniet » Tue Jul 13, 2021 10:07 pm

As Leto said, the real bug is actually in FG ALS filter blackout effect - I might try to fix that. You should be able to reproduce the issue in any aircraft by turning them on (View > ALS Filter Effects).

The Viggen part of the issue is that it automatically enables ALS filters, I will remove that.
For now you can delete line 374 in Aircraft/JA37/Nasal/ja37.nas :
Code: Select all
diff --git a/Aircraft/JA37/Nasal/ja37.nas b/Aircraft/JA37/Nasal/ja37.nas
index 77079c09..0c1ff95d 100644
--- a/Aircraft/JA37/Nasal/ja37.nas
+++ b/Aircraft/JA37/Nasal/ja37.nas
@@ -371,7 +371,6 @@ var Saab37 = {
       setprop("/gui/map/draw-traffic", 0);
       setprop("/sim/gui/dialogs/map-canvas/draw-TFC", 0);
     }
-    setprop("/sim/rendering/als-filters/use-filtering", 1);
   },
 
   # fast updating loop
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Re: Saab 37 Viggen

Postby idw » Tue Jul 13, 2021 10:49 pm

Thanks a lot for these quick answers, I've learned something today!
I've investigated the .xml model files but don't thought about the .nas files (not confident with these for now).
I have applied the suggested solution (delete the use-filtering line), it works fine!
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Re: Saab 37 Viggen

Postby colin_geniet » Sun Jul 25, 2021 12:15 pm

Version 5.1.0 is on FGAddon. Complete changelog is here: https://raw.githubusercontent.com/Nikol ... ngelog.txt

Most of the changes have already been announced in this post: viewtopic.php?p=385042#p385042. I'll just repeat them quickly:
  • Reworked right side, with a number of panels moved to the correct position (particularly on the AJS).
  • Reworked brakes system. Parking brakes operation: press brakes and pull parking brake handle (shift-B, handle is at the bottom-center of the front panel, below the radar screen) to lock. Press the brakes to release. Also there are chocks, don't forget to remove them (JA 37 > Toggle chocks).
  • Compositor clustered lights, if you are using FG next.
  • Custom 'Fuel and Payload' dialog.
  • New weapon panel for the AJS, with notably the weapon selector knob. See manual (section 4.3) for operation—it is not obvious.
  • Ground crew panel for the AJS, which you can safely ignore by default (settings are done automatically), but forces some restrictions on payload (see manual section 7.1).

In addition:

Radios
Completely reworked COM radios, working in VHF and UHF bands (roughly 103MHz­–160MHz and 225MHz–400MHz). Each radio can also use ~1000 preset channels, which can be configured in text files. The JA 37D has a primary radio (FR 29, left side) and a secondary one (FR 31, right side), plus a standby guard channel receiver. The AJS 37 only has a main radio (FR 22, left side) and a backup one (FR 24, left side, control panel shared with FR22) which is used for guard channel monitoring in normal operation.
In the cockpit, there's a new channel selector panel for the AJS, and minor changes to the other panels.
Image

Please read the flight manual (JA: section 3.1, AJS: section 3.2) regarding operation. If you just want to set a frequency, you still need to make sure that the radio is in the correct mode:
  • JA 37: Select mode N+L on the FR 29 panel, and press button MHz on the KV1 panel, then set the frequency on the bottom KV1 screen.
  • AJS 37: Select mode N+L on the FR 24 panel, and press button '—' on the channel selector panel, then use the frequency selection panel.

Fighter Link
I made significant changes to the fighter link.
Bad news: The new fighter link protocol is not backward compatible, so v5.0.0 and v5.1.0 of the JA 37 can't communicate together.
Good news: Fancy new symbols on the TI display; and each JA can set a personal 'identifier' (single digit), which is displayed on other JAs TI, to help distinguish between aircrafts in a same flight. More importantly, the new datalink protocol is designed to allow to easily add extensions (additional data to transmit) without breaking compatibility. Also, datalink will be coming to the F-16 soon! (already there on github version).
Beware, the KV3 panel (datalink channel) has changed: 1st digit is the aircraft identifier (which must be non-zero to work), and the channel is only the last 3 digits.
See manual section 3.1.5 for more details.


JA 37D Interoperability Mode
I made several small corrections to the JA 37 HUD and MI in interoperability (imperial units) mode, based on the real JA 37D flight manual.
There's also a few new obscure HUD features, controlled through the datapanel. Slightly more details are given in readme.ja37.txt
  • Terrain height can be displayed instead of radar altitude (REG/STR address 18 second digit)
  • In interoperability mode only: there is a QNH mode, which allows to set altimeters to QNH instead of QFE. Height calculations for takeoff and landing will compensate for airport altitude (ACDATA address 15 third digit).
  • In interoperability mode only: the HUD altitude scale can display a window for current altitude, and an airport index in QNH mode (ACDATA address 15 first digit. 0=off, 1=airbase index, 2=altitude window, 3=both).
HUD at landing, interoperability and QNH mode, with altitude window and airbase index:
Image


Miscellaneous Changes
  • A lot of additional switches and knobs have randomized settings when starting up (because I'm evil). Use the checklists and do cockpit checks in details! (or use autostart :mrgreen:)
  • Vertical field of view of the AJS HUD has been reduced a lot. To compensate, the HUD can be moved vertically (keybinding h), it should be down for takeoff and landing, up for cruise. JA is unaffected.
  • All instruments and displays show have been corrected to show true heading instead of magnetic, except for backup heading indicators. Thanks to vanosten for pointing out that issue.

Changes to Controls and Keybindings
Common:
  • w : suppress master warning
  • W : start/stop/reset chronometer
  • removed ctrl-n (target next waypoint) and f (intercept course to radar target)
JA only:
  • h : visual landing mode, when in landing mode, or with landing gear down (toggle aiming mode otherwise).
  • trigger must be held for 0.5sec to fire missiles
  • c : quick select missiles (instead of cycling through all weapons. TI must be used to select ARAK, C for cannon).
  • c/C (quick select missiles/cannon) no longer enable aiming mode.
  • u : disengage autothrottle (Instead of missile quick select, which is now c. As reminder, on AJS, u is both A/T disengage and IR missile quick select. Which is confusing, but that's how the real AJS works).
  • U : uncage IR seeker (same as AJS)
  • R : toggle IR seeker boresight mode in aiming mode (set reference altitude otherwise)
  • The TI menus for IR seeker boresight/uncaging are gone, use U/R instead. 'auto-uncage' mode no longer exists, when using boresight you need to press U in order to uncage the seeker.
  • (/) : change wingspan for A/A gunsight (without radar lock)
  • {/} : change distance for A/A gunsight (without radar lock)
AJS only:
  • h : toggle HUD position.
  • c/C : turn weapon selector knob
  • (/) : turn wingspan / bomb interval selector knob
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Re: Saab 37 Viggen

Postby colin_geniet » Sun Jan 23, 2022 3:47 pm

Version 5.2 is on FGAddon. Complete changelog: https://raw.githubusercontent.com/Nikol ... ngelog.txt
This is a fairly small release, with two main changes.

Firstly, there are new warning panels, with textures by valtsu41. For the JA 37, the changes are mostly visual. The AJS 37 now has distinct warnings, with significant differences on the right side. There also are both Swedish and English versions of the warnings. I also made a number of small changes to the logic of these warnings, but nothing major. You can check the panels description in the flight manual for details.

Here's how it looks (AJS, Swedish version):
Image Image

Secondly, I made a number of changes related to audio warnings.
  • Most important: all audio warnings have been removed from the AJS, except for master warning and high AoA warning. Sadly, the other only existed on the JA 37.
  • I broke the high G-load warning around one year ago, and somehow didn't notice. But it's back!
  • The conditions to trigger the high AoA / G-load warning have been improved a bit. They will try to anticipate the warning a bit, based on AoA / G-load rate of change, and stick movement.
  • For the AJS, the audio terrain warning is gone (with all others). But there's still a terrain warning, visual only! It shows with blinking altitude bars / radar altitude indices on the HUD, plus the big red light on the top left of the radar. But be careful, it is (intentionally) far worse than the previous, somewhat magical terrain warning. The new warning triggers under two conditions:
    1. When radar altitude is significantly less than barometric altitude.
    2. 7 seconds before ground collision, but only when radar is on, and the time of collision is based only on altitude, and vertical speed. If you fly horizontally into a mountain, you will never get a warning!
    So be careful when flying at low level!
    For now the JA 37 terrain warning is unchanged, although I plan to give it a similar treatment in the future.
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Re: Saab 37 Viggen

Postby colin_geniet » Tue Mar 15, 2022 7:54 pm

Development news: JA 37 has a new radar on the dev repository. Much of the credits goes to Nikolai, who made an impressive, generic radar system (currently used by F-16 and Viggen dev versions, coming to more aircrafts). It gives a much better simulation of different radar modes with their limitations, scanning patterns, tracking. Summary below, please refer to the flight manual for more details (sec. 4.3.4 Radar Display, 4.3.5 Radar Operation).

The radar has 3 main modes:
  • Scan: wide search mode. Radar echoes show as small bars on the radar display (MI), and are not tracked.
  • STT (Single Target Track): the radar focuses on tracking a single aircraft, and is blind to anything else ("hard lock")
  • TWS (Track While Scan): an intermediate, the radar scans a narrow (60°) pattern, and can track up to 4 aircrafts

F selects scan mode, and ctrl-f selects TWS mode. In either of these modes, a radar echo can be tracked by designating it with the MI cursor. Designating switches the radar to either STT or TWS mode, depending on the "cursor mode": when the cursor is a cross, designating gives TWS mode, and when the cursor is a chevron, it gives STT mode. "Cursor mode" is changed with f. In either case, designating an aircraft makes it the primary track, and disables the cursor. When there is a primary track, f switches between STT and TWS modes. Pressing the designate button again will either stop tracking (in STT) or make the primary track secondary (TWS), and restore the cursor in either case. In TWS mode, one can also cycle through secondary tracks with m.

Dogfight mode
There is an additional radar mode, called disk search mode, or dogfight mode. It scans a disk of radius 10° straight ahead, and automatically locks (STT) any radar echo it finds.
This is not the same thing as the HUD visual aiming mode (shown as SIKT / AIM on the MI), although the two interact:
  • Reminder: h toggles visual aiming mode, as long as the landing gear is up and locked.
  • N engages disk search mode, visual aiming mode, and turns the radar on
  • In visual aiming mode, r turns the radar off (otherwise r toggles radar on/off as it used to). This matches controls on the real JA37D, the idea being that in aiming mode, one will want to turn the radar on in disk search mode (N).

Scan arcs
This radar properly simulates radar sweep pattern, and thus will only see within limited horizontal and vertical arcs (unlike the old radar, which magically saw everything in a 120° by 120° square). In particular, it is easy to miss an aircraft flying at a different altitude if one does not adjust search height.
  • In scan mode, the radar scans the full 120° horizontal arc, and a ~12° vertical arc (adjustable up / down with < / >).
  • In TWS mode, the radar scans a narrower 60° horizontal arc, and a ~8° vertical arc. If there is a primary track, the scan pattern is centred on the later. Otherwise, the horizontal scan arc moves left and right following the MI cursor, and the vertical arc can be adjusted as in scan mode.
Scan arcs are displayed on the MI and TI. Horizontal scan arc shows as horizontal lines at the top and bottom of the MI, and as an arc on the TI. The vertical scan limits are shown on the TI sideview, and indirectly on the MI altitude scale: a thick vertical line shows the range of altitude covered by the radar, at the range corresponding to the MI cursor.

IFF
IFF (identification friend foe) has changed a bit: IFF interrogation is never done automatically. It is started with n, lasts for around 10s, and any aircraft within the radar scan pattern is interrogated, showing as a cross on the MI if friendly. For tracked aircrafts only, the response is stored, and displayed on the TI and HUD: friendly shows as a cross in both. Furthermore, TI shows friendlies in green, hostile (lack of IFF response to an interrogation) in red, unknown (no interrogation) in yellow. (TI and HUD also use information from datalink.)

New MI stuff
  • Two "cursor modes" (STT/TWS, see above)
  • Radar scan arcs (see above)
  • Different variants of the tracked echo symbol: primary track shows as a '#' as previously. If it is not yet acquired, it instead shows as a large square. Secondary track symbols are similar, with the middle of each line missing: it shows as 4 corners pointing outwards, or the 4 corner of a square when not yet acquired.
  • Altitude of primary track is displayed on the altitude scale as a thick mark.
  • Chaff/flare count on the lower left.
  • Selected weapon min/max range show in the radar area as 4 brackets. Horizontally, these brackets match the horizontal scan arc.
  • When a datalink track is selected on the TI (see below), its position and altitude is shown with circles in the radar area and altitude scale.

New TI stuff (not in the manual, sorry!)
  • Both primary and secondary tracks are shown, with same symbols as the MI. (both are also shown on the HUD: primary track is an upper half circle, secondary are upper half squares)
  • When the MI cursor is active, the TI shows a ghost cursor (diagonal cross) which matches the geographic position of the MI cursor.
  • Radar vertical limits are shown on the sideview (see above).
  • Designating a track (radar or datalink) with the TI cursor selects it as "destination" for the various display and instruments showing bearing and range to waypoint. If it is a datalink track, it is displayed on the MI to help with finding it on radar. (The first half is something which used to work, and which I am guilty of completely breaking in previous updates. But it's back, and better!).
  • SYST>RR button (top left) cancels the previous selection. It also cancels landing mode. (Except on the ground, where it instead turns displays on/off).
  • M toggles the cursor between MI and TI.

And a picture:
Image
Green aircraft on TI is on datalink, and is tracking a second aircraft (yellow). The second aircraft is selected on the TI, and I'm about to designate it on the MI.

Finally, some AJS 37 news:
I made a quick and dirty port of the AJS radar to the same new radar system. The only significant change is the limited vertical scan arc (~6°). It can be adjusted up and down same as the JA, and this is shown on a small horizontal scale at the top of the radar display (left is down, right is up).
However, I am working on a completely new ground mapping radar for the AJS. It is very much in development, but you can give it a try on the branch CI.
Image Image
colin_geniet
 
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Re: Saab 37 Viggen

Postby Necolatis » Sat Dec 10, 2022 4:04 pm

The Flightgear Viggen this month has 10 year anniversary.
I started the development around December 2012,
have put tons of hours into it, and then Colin took over
and has made some amazing updates. It has come a long way.
"Airplane travel is nature's way of making you look like your passport photo."
— Al Gore
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Necolatis
 
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