Radar warning receiver

The War Thunder standard RWR display showing a pulse-Doppler "track" from the 5 o'clock sector.

A Radar Warning Receiver (RWR) is a system that informs the pilot about incoming radar radiation, allowing for proper action if needed. In-game, the RWR varies a lot between models, but most of them are a clock display which shows the type of threat (search radar or tracking radar), the source, and the direction.

Understanding the RWR

Note: Radar Warning Receivers are only capable of detecting certain bands. Radars that operate at frequencies outside of those bands will not be detected.

Basic function

The RWR warns the pilot about any outside radar that may be detecting, tracking, or launching a radar-guided missile at the user's aircraft, as long as the threat isn't in the RWR's blindspots (often directly above or below).

If a radar is sending a single "ping" at you (a search radar is detecting you), the RWR will sound a short warning and show the direction it is coming from. RWR can show multiple pings at once from different directions and sources. If you hear a constant alarm and see a dashed line coming from the ping towards the center of the RWR, a tracking radar has locked you and is constantly tracking your position (which usually precedes a missile launch). Finally, a faster alarm along with blinking warnings in the RWR indicate a missile launch, which requires immediate action.

Most RWR have dead angles from which they can't see the enemy radar, particularly from directly above or below.

Some RWRs are incapable of distinguishing between search radars and tracking radars. If your RWR is one of them, instead of a constant alarm you may only be able to distinguish between the two by how frequently the ping updates (A constant tone that doesn't go away may indicate a tracking radar).

There may be lamps which indicate the type of radar that's detecting or tracking the aircraft, for example PD (Pulse-Doppler), A/D (Air Defence), AAA/AI (Anti-Aircraft Artillery/Airborne Radar) and much more, although the most dangerous of them all is CW which is the guidance method for most SARH missiles.

There are many types of RWR which vary a lot in function:

Standard RWR

This type of RWR is the one that's commonly found on most aircraft that carry one. They display the exact direction and the type of threat that's detecting the aircraft.

Many of them are capable of detecting tracking radars, and some can even detect if the threat has launched a radar-guided missile, allowing for immediate evasive action. More advanced RWRs may be able to identify the vehicle that's triggering the RWR as long as they're inside the RWR's database.

Sectored RWR (SPO-10, SPO-15 and others)

SPO-10 RWR.

A Soviet SPO-15 RWR.

This type of RWR doesn't display the exact direction of the detected threat, and instead only shows it in sectors due to the placement of RWR receivers. One of the most common RWRs that use sectors for displaying threats are the SPO-10 used by the MiG-21, early MiG-23 variants and certain PLAAF jets with equivalent system, which only show 4 sectors around the aircraft; while MiG-29 and Su-27/J-11(A) series opted for a more divided SPO-15 (L-006LM) with 4 sectors per each frontal aspect receivers, only one receiver with two sectors for the rear aspect as shown on the display unit. Each sector shows an approximation of the direction of the target, although it has its limitations. In order to show that a target is directly ahead, the RWR has to light up 2 sectors that look forwards, and if a target is directly behind, it has to light up 2 sectors that look backwards. This could be easily confused for two different threats that are triggering the RWR system.

For example, due to the placement of antenna and receivers on Su-27 series, it has a dead zone right below the aircraft; although the system was said to identify multiple threats, the sectored display can only at most tell the target's azimuth and its altitude relative to the aircraft (B; H represents High Высокий and Low Низкий) at front aspect; players need to pay extreme caution in case of enemy's tailing.

Semi-Directional RWR (SPO-2)

Unique to the Su-7B family of jets and the MiG-19 series, this RWR only warns about radiation that's coming from behind as it only has a single antenna. Historically, this RWR was designed to warn the pilot about an enemy that was using the rangefinder radar behind the aircraft, but in-game it gives proper warnings up to 40 km away as long as the radiation is an I Band type coming from the rear. Note that this RWR lacks tracking capability.

RWR with no tracking capability (AN/ALR-45, AN/APR-25,APP F9/5, SPO-2, APP-73 and others)

These RWRs function like normal with a key difference: If a radar locks the aircraft, there won't be a special text and audio warning, forcing the user to be more attentive to the RWR display and sounds.

However, these RWRs can still show the difference between a search and a tracking radar, as once the plane is being tracked, the search ping extends into a constant tone that won't go away, along with the ping icon refusing to fade away.

Note that even if the RWR lacks tracking capability, it may still be able to give proper missile launch warnings if the RWR has that capability.

Symbols

AI (Air-to-Air) - Air Intercept Radar
AI R/O - Airborne Rangefinder
AI HI - Air Intercept Radar in high frequency band
AI TRK - Air Intercept Radar in track mode
PULSE - Pulse signal
PD (Pulse Doppler) - Pulse Doppler Radar
IPD - Intercept Pulse Doppler
MPRF - PD with medium pulse repetition frequency
HPRF - PD with high pulse repetition frequency
CW - Continuous Wave signal (Guidance method of most SARH missiles)
ICW - Intercept Continuous Wave signal
CW/PD - CW or PD signal
A/D (Air Defence) - Air Defence System
SAM (Surface-to-Air Missile) - SAM Radar
SAM LO - SAM low frequency band
SAM MID - SAM medium frequency band
SAM HI - SAM high frequency band
SAM TRK - SAM Radar (Tracking)
SAM LNC - SAM in launch mode
AAA (Anti-Aircraft Artillery) - Anti-Aircraft Artillery
AAA/AI - Anti-Aircraft Artillery or Radar/Airborne Radar
AAA LO - AAA in low frequency band
AAA TRK - Anti-Aircraft Artillery Radar (Tracking)
TWS - Track While Scan
S125 - S-125 Neva (NATO: SA-3 Goa)
S75 - S-75 Desna (NATO: SA-2 Guideline) and derivatives
SA75 - SA-75 Divina (NATO: SA-2 Guideline) and derivatives
N-H - MIM-14 Nike-Hercules
HAWK - MIM-23 Hawk

List of RWR systems


Name	Band									Track indication	Equipped by
Name	C	D	E	F	G	H	I	J	K - M	Track indication	Equipped by
ALR-400											EC-665 Tiger HAD EC-665 Tiger HAP EC-665 Tiger UHT Tiger HAD Block 2
AN/ALQ-73											F-104S.ASA
AN/ALR-45											A-7E
AN/ALR-45(V)											F-4J Phantom II F-4S Phantom II F-14A Early
AN/ALR-46											F-20A
AN/ALR-46(V)3											F-4E Phantom II F-5E Kurnass Kurnass 2000 ␗F-5E ▄F-5E FCU
AN/ALR-56C											Baz Baz Meshupar F-15A F-15C MSIP II
AN/ALR-56M											F-16D Barak II F-16A F-16AJ F-16C Netz ␗F-16A MLU
AN/ALR-67(V)2											A-6E TRAM AMX AMX A-1A AV-8B Plus AV-8C F-14B ▄AV-8B Plus
AN/ALR-68(V)											◄F-4F
AN/ALR-68(V)3											◄F-4F KWS LV
AN/ALR-69											A-10A A-10A Late F-16A ADF ▄F-16A ▄F-16A ADF
AN/APR-25											A-4E Early Ayit F-4C Phantom II F-5A F-5C F-100D F-104C F-104S F-105D Jaguar A Kfir Canard ␗F-5A ␗F-100A ␗F-104G ▄F-100D ▄F-104G ▄F-104G ▄F-104S TAF ▄Mirage 5BA ◄F-104G A-4E A-4E Early (M) A-4H
AN/APR-27											F8U-2 F-8E
AN/APR-32											F-4J(UK) Phantom II
AN/APR-36											A-7D A-7K Buccaneer S.1 Sea Vixen F.A.W. Mk.2 ◄F-4F Early ◌Hunter F.58
AN/APR-39											A.109EOA-2 AH Mk.1 Apache AH-1F AH-1S AH-1S Kisarazu AH-1W AH-6M AH-64A AH-64A (GR) AH-64D AH-64DJP AHS BO 105 CB-2 BO 105 PAH-1 BO 105 PAH-1A1 G-LYNX HKP9A Lynx AH.Mk.1 MH-60L DAP Peten Rooivalk Mk1F CSH Saraph Tzefa B Tzefa D/E YAH-64 ␗AH-1W ▃AH-64A Peten ▅AH-1E AH-60 AH-64A Peten
AN/APR-39A(V)1											AH-1Z OH-58D ␗OH-58D
AN/APS-54											B-57B
AN/APS-109											F-111A
APP F9/5											A32A A32A Röd Adam
APP-27											AJ37 AJS37
APP-73											JA37C JA37D
AR830											JAS39A JAS39C ▄JAS39C ◔JAS39EBS HU C
ARI 18223											Harrier GR.3 Jaguar GR.1 Jaguar GR.1A Jaguar IS
ARI 18228											Buccaneer S.2 Phantom FG.1 Phantom FGR.2 Sea Harrier FRS.1 Sea Harrier FRS.1 (e)
ARI 18228/10											Buccaneer S.2B
ARI 18228/19											Sea Harrier FA 2
ARI 18241/1											Tornado ADV Tornado F.3 Tornado F.3 Late
ARI 23284											Tornado GR.1 ▄Tornado IDS (1995) ◄Tornado IDS ASSTA1 ◄Tornado IDS MFG ◄Tornado IDS WTD61
ARI 23333/1											Harrier GR.7
CARAPACE											▄F-16AM
ELT/156											A129CBT A-129 International (p) AH-129D
J/APR-1											F-104J
J/APR-2											F-4EJ ADTW F-4EJ Phantom II
J/APR-3											F-1
J/APR-4											F-15J F-15J(M)
J/APR-6											F-4EJ Kai Phantom II
KJ8602											A-5C J-7E Q-5L
KJ8602A											J-8F JH-7A
L-150-16M											Su-25SM3
Mirage Detecteur											Mirage 5F Mirage F1C Mirage F1C-200 Mirage IIIE Shahak
RWR											Z-9W Z-9WA Z-10 Z-19 Z-19E
SERVAL											Mirage 2000-5F Mirage 2000C-S4 Mirage 2000C-S5 Mirage 2000D-R1 Mirage 4000
SPO L-150											Ka-52 Mi-28N Mi-28NM MiG-29SMT Su-25T Su-27SM Su-39
SPO-2											J-6A MiG-19PT Shenyang F-5 Su-7B Su-7BKL Su-7BMK ␗F-100F ◄MiG-21 SPS-K ◊MiG-19S
SPO-10											J-8B Mi-24P Mi-24V MiG-21S (R-13-300) MiG-21SMT MiG-21bis MiG-23M MiG-23ML Su-17M2 Su-22M3 Yak-38 Yak-38M ▂Mi-24D ▄MiG-21bis ◄Mi-24P HFS 80 ◊Mi-24P ◊MiG-21 "Lazur-M" ◊MiG-21MF ◊MiG-21bis-SAU ◊MiG-23BN ◊MiG-23MF ◊MiG-23MLA ◔Mi-24D ◔MiG-21MF ◔MiG-21bis-SAU ◔MiG-23MF ◔Su-22M3
SPO-15											Ka-50 Mi-28A MiG-23MLD MiG-27K MiG-27M MiG-29 Su-25 Su-25K Yak-141 ◄MiG-29G ◊MiG-29 ◊Su-22M4 ◊Su-22UM3K ◔MiG-29
SPO-15L											Su-17M4
SPO-15LM											J-11 J-11A Mi-35M Su-25BM Su-27 ◔Mi-24P ◔Mi-24V
SPS-200											Kfir C.2 Kfir C.7
Sherloc											Mirage F1CT Super Etendard
TARANG											▄MiG-21 Bison
Type 930											Q-5A
Type 930-4											J-7D