"The radar system has been overhauled to be more realistic. Different factors such as the Doppler effect, ground clutter, and radar cross-section come into play when you or the enemy are trying to detect and lock targets. You'll also need to consider that your radar emissions can be detected by others much further (via RWR) than your receiver can detect returns. New Anti-Radiation weapons will allow you to target enemy radar signals to keep the sky safe from air defenses." - Update v0.0.11
Radar is used by a unit to detect and track other units. This information is fed to weapons or other allied units. Radar can affect the detection condition affecting AI behavior and mission editor functions.
When within range and line of sight, a radar emitter may appear on the RWR and ARAD, but not necessarily change the emitter detection condition as shown on the map. This works both ways. For example, a far away unit may suddenly appear on the player's RWR, but will is not visible on the map. The player may also be too far to return a meaningful signal. In this case both are undetected. However, the player can use the radiation source as a target for an anti-radiation missile, or to get a bearing to get a target.
Similarly, there can be an enemy air unit beyond visual range that does not detect you on their radar yet. Upon sensing your radar source, they will turn and fly towards it. Once you appear on their radar, or are within visual range, you are flagged as detected.
Active radar homing missiles appear on the RWR once they turn on their radar.
Aircraft can use their onboard radar to guide missiles and guns.
Aircraft must first lock a target with their onboard radar. Active radar guided missiles are then authorized for launch and initially navigate based on the aircraft's radar calculations. After a some delay, the missile navigation switches over to the built in radar. Also, the radar can be used instead of the targeting pod to calculate firing solutions for guns against air targets.
Ground unit surface-to-air (SAM) missile launchers need to be paired with at least one ground based radar station. This will be responsible for detecting a unit, authorizing a launch from a linked SAM launcher, and providing initial guidance. It is not known if the SAM launcher is chosen based on proximity to the target or best range taking into account leading the target's trajectory. Similar to air based missiles, the SAM will switch over to its own onboard radar to home onto the target.
Sea unit SAM operate similar to ground ones but are closed systems. Destroying all onboard radars will render all onboard SAM systems inoperable. Ships in a unit group share unit detection information, but cannot launch each other's SAMs.
As of the most recent Public Testing version, the previously experimental realistic radar has become a permanently turned on feature.
Chaff is used as a radar decoy. Essentially strips of metal deployed to reflect radar back at the enemy missile or fire control radar, creating decoy signals. Ideally, chaff deployment should be coupled with changes in direction, such as beaming. With each change, a group of chaff should be deployed creating decoys at each turn. An example would be while performing notching or beaming maneuvers described below.
However, they may not be able to steer away in time from hills and structures. Beaming a missile forces it to take longest path towards you as it leads your trajectory. When beaming takes into account radar mechanics, this is called notching (see below). Beam by default (smoke trails or wingmen radio warnings), and notch once the missile is identified as radar guided (visual or audio cockpit cues). It should be noted that beaming can be done horizontally or vertically. If you beam the missile (turn 90° towards its heading) and accelerate to a high speed, it's going to point very far to the left or right of your location — especially if it is still far away. Make a 180° turn to beam in the opposite direction, and the missile will have to drag itself all the way around to point in the other direction. This maneuver uses up valuable energy that could otherwise be spent gliding a longer distance.
Notching: Refers to a tactic taking advantage of the Doppler effect and using it to lose the lock of a radar source. Essentially radar systems filter out things like terrain as "clutter" because those objects are neither going towards or away from the source radar. This means that enemy radar systems, including those on missiles, track objects when they are going towards (higher frequency ping) or away (lower frequency ping) from them. The concept of notching means that by turning your aircraft to place the missile or radar system as close to your 3 or 9 o'clock as possible you are now neither going away from or towards the radar source. This can cause the radar to see you as "clutter" and filter you out, losing the lock. Ground clutter and aircraft aspect is now taken into account, and it is now possible to "Notch" a missile. Missiles are smart enough to lead the target without leading themselves into the ground.
Currently, all radar guided missiles in game use external radar for initial homing. Identify this source on RWR or ARAD and notch that. When the missile switches to its built in radar as shown by an audio and visual RWR cue, notch this instead.
Terrain masking is a common tactic used by pilots flying into enemy territory where radar is expected. It involves flying as low as possible, using obstructions and terrain to block radar tracking. One of the easiest and most reliable ways to evade any inbound missile, or lose a fire control radar lock is to simply no longer be visible to it due to terrain obstruction. Terrain masking also is used to infiltrate well into enemy territory and conduct surprise attacks without having to waste munitions on defeating an enemy's entire air defense.
Units with Radar
F/A-26B Radar Quick Guide
How to Use the F/A-26B Radar to Fire the AIM-120 Missile
- Turn on Radar switch to ON
- Set one of your MFD's to RADAR
- MFD Buttons R+ and R- adjust the range. Use R+ to max until you see 60 and 30 mark green lines for max range
- Point your nose towards contact (diamond)
- Make your RADAR SOI, watch closely until red planes appear
- Enemy aircraft are red icons
- Friendly aircraft are blue
- Missiles are circles
- Use the SOI controller (trackpad/joystick) to move the green brackets on target
- Press ONCE to identify target,  should appear on the left of MFD identifying it as target number 1. Repeat for multiple targets and each one will be numbered.
- DOUBLE press to get a lock on the target (STT - Single Target Track),
- Select AIM-120 missile
- Missile range will be visible on the right side of the HUD as a vertical bar on the right hand side with a little pointer/arrow.
- The bar represents the max range of the missile against the target continuously calculated as you and the target maneuver. When the arrow is within this range the missile may be fired and the yellow launch lights turn on.
- The double bar represents the no-escape range. If you fire when the arrow is there the enemy cannot escape the missile (but they can still defeat it with chaff and other methods)
- On the HUD, the enemy aircraft trajectory pointer (the small solid dot), doesn't have to be in the circle, but its desired as it represents an optimal path for missile trajectory
- The missile indicator on lower left HUD should show something like T-43s which is predicted time to impact.
- The target does not need to stay STT locked all the time but it has to be WITHIN scanning range of radar until missile goes Pitbull (T changes to M), at which time the missile goes active and you can break the lock
Boresight mode is for working for < 15 km and should be only used for close range. When in boresight mode, the radar will lock on to the first aircraft to enter the circle in the HUD. Be sure not to accidentally lock a friendly fighter while in boresight mode.