AGM-45 Shrike Anti-Radiation Missile

agm45

The Sparrow-derived AGM-45 Shrike is an early attempt at an anti-radiation missile for the suppression of enemy air defense (SEAD) role. Mating a frequency-tuned seeker with the rocket body of an AIM-7, the Shrike provided the United States Navy, and later the United States Air Force, with a standoff option for the engagement of enemy SAM radars. While nominally effective, in practice the Shrike was a difficult weapon to employ properly, given its limited range, low speed, and primary engagement mode that left the launching aircraft within lethal envelopes of most opposing air defense systems. Further reducing its potency was a small warhead, meaning that in most instances only the emitting antenna itself was damaged, rather than the vehicle it was mounted to.

While limited in most respects, the Shrike received a number of upgrades over its lifetime, lasting in service from the mid-60s in Vietnam, until just after the Gulf War, through better engines and additional seeker updates for later SAM systems. The Shrike was put into use by two foreign users - the Israeli Air Force, who also modified it for a ground-launched version, and through clandestine means with the RAF during the Falklands War.

Variants

Only the A version can be equipped on this version of the Phantom.

Employment

The AGM-45 has three separate launch modes available: (WRCS) AGM-45, (LABS) LOFT, and (WRCS) DIRECT.

Basic cockpit setup

Before any AGM-45 Shrike can be employed a few things have to be set in the cockpit by the pilot:

  1. Select the station for the Shrike you want to employ via the station select buttons
  2. Select ARM on the weapon select knob
  3. Select one of the three available modes of the Shrike via the delivery mode knob
  4. (optional) Turn the flight director on for ADI needle guidance
  5. (optional) Turn the LCOSS to A/G
  6. Turn MASTER ARM on

AGM-45 (WRCS Mode)

Used only with the AGM-45 in conjunction with the WRCS, this mode is the primary means of employment of the Shrike. The mode is based around a high altitude attack profile, and depends on the pre-programmed weapon engagement envelope of the AGM-45 stored within the WRCS. This profile, in conjunction with current aircraft state information from the INS and a signal provided by the receiver in the missile - having detecting an emitter of the type its attuned to, define a flight path and release envelope for optimum probability of the missile reaching the target.

With the WRCS mode selected to AGM-45, the run is initiated by arming a station select button for a hardpoint carrying an AGM-45 missile. Doing so activates the missile's receiver, and upon emitter acquisition will provide the aforementioned information signal to the WRCS. The WSO should enter a target altitude value into the computer control panel, if necessary, using a mean value for the current target area, and if multiple missiles are to be launched, a release advance time setting. The WRCS receives both data from the missile regarding look angle from the missile, along with corrected look angle from the INS; the selection for which data to use is performed with the TGT/MSL Rej switch, that should, in most cases, be left in the DF REJ position.

Look angle and estimated range available, the WRCS will provide guidance instruction using the needles on the ADI. Once oriented in the dive angle, the horizontal range to target will be provided on the HSI and BDHI, so long as the INS position is selected for navigation mode.

When the aircraft's orientation is correct and the ADI needles are centered, once the aircraft is within missile range, one of the indexer lights will illuminate based on the detected range to target to instruct the pilot as to the required release maneuver - dive, level, or pull-up. At this time, the pilot can press and hold the bomb release button to initiate the attack. Once the release range is attained in the instructed profile, the missile will be launched.

πŸ’‘ Special note must be made of the importance of maintaining the ADI needles centered, especially the vertical azimuth relationship. Because the orientation of the missile itself when installed on the wing can cause offset of its receiver to occur when the aircraft is banked, preparation of the attack may require repeated adjustments with wings brought to level every few seconds to make certain the aircraft is pointing at the emitter.

agm_45_commands Commands of the AGM-45 Shrike in WRCS mode

Pull-up

The Pull-up command light indicates that the aircraft is at some range where the Pull-up maneuver must be flown to get a release signal. After pickle and with the indexer light indicating Pull-up, the Pull-up instruction is guidance for the pilot to initiate a steady rotation back to the horizon, and, if desired, continue into a steady climb state until range requirements are met and the missile is launched. The pilot can choose to either bring the aircraft to near level and stop, or pull further into a low climb profile. When the aircraft is approximately 5 seconds away from release, the level indicator will illuminate, directing the pilot to maintain the current orientation until the Shrike is away.

Dive

The dive command in the WRCS mode occurs only when the attack is initiated very close to the target. The situation and proximity to the SAM installation must be considered prior to attack commitment with the pickle button, as any response by the battery has a high probability of arriving before the missile can potentially kill the emitter. The dive command, once followed, will then be followed with the level indicator once missile launch imminent.

Level

The level instruction is less of a directive than a confirmation of impending launch. Depending on the initial attack setup, the level signal may immediately occur, or occur quite soon after one of the other two instructions. From that point, it is simply required that the pilot maintain the current state for best chance of missile success.

WRCS AGM-45 Employment

πŸ’‘The WRCS mode is currently WIP and will the employment will be described once it is ready

Loft

The Loft attack profile of the Shrike is like a loft bombing attack, utilizing the weapon lookup tables to define a suitable IP to release distance, the necessary release angle, and the time from IP to pull-up is determined by the lookup table speed versus the IP to release distance.

One key difference in the Loft mode versus the WRCS employment modes for the Shrike is the primary usage of the NORM mode rather than DF REJ; this places the missile's receiver in the role of the azimuth guidance directive on the ADI rather than the INS. The ADI's vertical needle will appear when the AGM-45 position is selected on the pedestal switch which is the NORM position.

The attack is performed like a loft bombing profile; the Phantom is flown over the IP at the intended altitude and airspeed, with the bomb release button being held from the point of flyover. The countdown timer initiates, the horizontal ADI bar appears to maintain level flight, and the pull-up lamp illuminates. When the pull-up timer runs out, the pull-up lamp will turn off, the sight reticle will turn off, and the horizontal ADI bar will move to display G load as normal for the pull-up maneuver; a correct profile will keep both ADI bars centered. When the aircraft achieves the programmed release angle, the missile will launch. Once launch has occurred, the pull-up lamp and sight reticle will illuminate again, and the horizontal ADI bar will stow.

manual_loft_bombing Example of the Loft bombing, the procedure stays the same for the AGM-45 Shrike

LABS Loft Employment

This mode works exactly the same as it would for bombs so pre-planning is necessary. Select an IP calculate the timers and fly the same attack profile as for Loft bombing. Note that in this mode the Loft seeker of the AGM-45 Shrike needs to sense a differential pressure of 1 Bar and needs to sense a barometric height of over 18,000ft to arm itself and start searching.

Direct Mode

Direct mode employment of the AGM-45 is dependent on the crew knowing the precise location of the target SAM emitter; while it can be utilized as a fallback method in event of a WRCS system failure, the need for at least 10 degrees of dive angle against the target for successful delivery places a premium on being able to plan the attack against a specific point on the ground.

To employ the weapon in Direct mode, the crew confirms receipt of emitter audio, and initiates a dive to center the ADI needles at the target. The crew should then check the dive chart for angle and AGL, and the pilot should maneuver into that orientation, maintaining a centered vertical ADI needle. From that point, the bomb release button is pressed and held until the Shrike is fired.

WRCS Direct Employment

For a direct employment all the pilot has to do is center the needles on the ADI and press the bomb release button. The Shrike will fire within one second after pressing the bomb release button. Be aware that the Shrike will have the least amount of range in direct mode and should be fired very near to the target. A dive angle of 20 degree or more is recommended.

Seeker Heads

The AGM-45 has 10 seeker heads, which each target a specific emitter radio frequency, to select from. This means some preparation is required prior to flight in order to be properly prepared to engage the threats effectively. The following seeker heads tables are provided so your missions can be planned accordingly.

πŸ’‘ This seeker head data was last updated for 2.9.7.59263.

Seeker RF Limit Table

SeekerPrimary TargetsLower RF Limit (GHz)Upper RF Limit (GHz)
Mk 22Fan Song (SA-2 TR)4.85.2
Mk 23Fan Song, Fire Can, Tin Shield24
Mk 24 Mod 5Fire Can, Tin Shield2.653.15
Mk 24 Mod 34Fire Can, Tin Shield2.53.5
Mk 25Fan Song (SA-2 TR)46
Mk 36Low Blow (SA-3 TR)7.99.6
Mk 37Flat Face0.81
Mk 49 Mod 0Low Blow, Straight Flush (SA-6 STR)610
Mk 49 Mod 1Low Blow, Straight Flush (SA-6 STR)610
Mk 50Various26

General Key:

  • SR: Search Radar
  • TR: Tracking Radar
  • STR: Search and Tracking Radar
  • RF: Rangefinder

Land-based Threats

Warsaw Pact land-based SAM and EWR system radars
SeekerSA-2SA-3SA-5SA-6SA-8SA-10SA-11SA-13SA-15SA-19EWR
Mk 22TR/RFTRSR/TRTRSR/TRDE
Mk 23TR/RFTSTS/BBTRSR/TR
Mk 24 Mod 5TR/RFTSTSTRSR/TR
Mk 24 Mod 34TR/RFTSTSTR
Mk 25TR/RFTRSR/TRTRSR/TRDE
Mk 36TR/RFTRTRTRCS/TRSR/TRTR
Mk 37FF/RFFFFF/TRTR
Mk 49 Mod 0TR/RFTRTRTRSTRCSSR/TRTR
Mk 49 Mod 1TR/RFTRTRTRSTRCSSR/TRTR
Mk 50TR/RFTS/TRTS/BBTRSR/TRDE

πŸ’‘ The SA-2/3/5 all can use the same Flat Face search radar with the SA-5 having the option of using the Tin Shield as a search radar as well.

  • BB: Big Bird (SA-10 Search Radar)
  • CS: Clam Shell (SA-10 Search Radar)
  • DE: Dog Ear
  • FF: Flat Face (SA-2/3/5 Search Radar)
  • TS: Tin Shield (SA-5/10 Search Radar)
Chinese land-based SAM Threats
SeekerCH-SA-4 (HQ-7)
Mk 22
Mk 23
Mk 24 Mod 5
Mk 24 Mod 34
Mk 25
Mk 36SR/TR
Mk 37
Mk 49 Mod 0SR/TR
Mk 49 Mod 1SR/TR
Mk 50
Combined NATO and Warsaw Pact Anti-Aircraft Artillery (AAA) radars
SeekerShilkaFire CanGepardM163 VADSC-RAM
Mk 22TR
Mk 23TRSR/TR
Mk 24 Mod 5TRSR/TR
Mk 24 Mod 34TR
Mk 25TR
Mk 36TR
Mk 37TR
Mk 49 Mod 0TR
Mk 49 Mod 1TR
Mk 50TRTR
NATO land-based SAM system radars and EWRs
SeekerHawkPatriotRapierRolandNASAMS
Mk 22STRTR
Mk 23TR
Mk 24 Mod 5TR
Mk 24 Mod 34TR
Mk 25STRTR
Mk 36TRTRTRSR
Mk 37SRTR
Mk 49 Mod 0TR
Mk 49 Mod 1TR
Mk 50STRTR

πŸ’‘ Ship classes, and not individual ships, are listed where ships are identical.

Soviet Naval Threats
SeekerKirovSlavaKuznetsovMolniyaGrishaKrivakNeustrashimyRopucha
Mk 22TRTRTRTRTRTR
Mk 23SR/TRSR/TRSR/TRSR/TRTRTRSR/TR
Mk 24 Mod 5SR/TRTRSR/TRSR/TRTRTRSR/TR
Mk 24 Mod 34TRTRTRTRTRTR
Mk 25TRTRTRTRTRTR
Mk 36SR/TRSR/TRSR/TRSR/TRTRTRSR/TR
Mk 37TRTRTRTRTRTR
Mk 49 Mod 0TRTRTRSR/TRSR/TRTR
Mk 49 Mod 1TRTRTRSR/TRSR/TRTR
Mk 50SR/TRSR/TRSR/TRSR/TRTRTRSR/TR
Chinese Naval Threats
SeekerType 052BType 052CType 054AType 071
Mk 22TRTR
Mk 23SR/TRSR/TRSR/TR
Mk 24 Mod 5TRSR/TRTR
Mk 24 Mod 34TRTR
Mk 25TRTR
Mk 36SR/TRSR/TRSR/TR
Mk 37TRTR
Mk 49 Mod 0TRTR
Mk 49 Mod 1TRTR
Mk 50SR/TRSR/TRSR/TR
US Naval Threats
SeekerTiconderogaArleigh BurkeOliver Hazard PerryForrestalNimitzTarawa
Mk 22TRTR
Mk 23TRTR
Mk 24 Mod 5TRTR
Mk 24 Mod 34TRTR
Mk 25TRTR
Mk 36TRTRTRTR
Mk 37SR/TRSR/TRSR/TRTR
Mk 49 Mod 0TRTR
Mk 49 Mod 1TRTR
Mk 50TRTR
British Naval Threats
SeekerLeanderCastleInvincible
Mk 22TR
Mk 23TR
Mk 24 Mod 5TR
Mk 24 Mod 34TR
Mk 25TR
Mk 36TR
Mk 37TR
Mk 49 Mod 0TR
Mk 49 Mod 1TR
Mk 50TR
Other Naval Threats
SeekerVeinticinco de MayoCondellTiger
Mk 22
Mk 23SR/TR
Mk 24 Mod 5
Mk 24 Mod 34
Mk 25
Mk 36
Mk 37
Mk 49 Mod 0
Mk 49 Mod 1
Mk 50SR/TR