Thread by @noclador

How did the US mount AGM-88 HARM missiles onto Ukrainian fighters... well, I think I know how. A short thread 🧵:

AGM-88B/C-1/D missiles have three operation modes:

• Self-Protect (SP)
• Target Of Opportunity (TOO)
• Pre-Briefed (PB)

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When US Air Force F-16CM Falcon or US Navy EA-18G Growler fighters fly Wild Weasel missions they use Self Protect mode.
In this mode the Falcon's AN/ASQ-213 HTS R7 (to the left of the air inlet) and the Growler's AN/ALQ-218(V)2 (on the wingtips) sensor systems detect, locate,
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analyze, and identify sources of radio frequency emission. Once a threat is identified the pilot transmits the target data to the missile and launches it.

There is no chance this would work with Ukrainian fighters as US sensor systems can't be installed on Ukrainian planes
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and there is no way to transmit targeting data to the missiles.

Self Protect mode can also be used with aircraft like the F-15C, F-15E, F/A-18C (photo), which lack the aforementioned sensor systems.
In this case the aircraft's own less accurate, less powerful radar warning

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receiver would be used to identify targets. This would also not work with Ukrainian planes as there is no way to transmit the targeting data to the missiles.

In the Target Of Opportunity mode the AGM-88's own passive radar homing seeker scans for and detects targets.

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Once the missile detects a target it transmits the target data to the plane's avionics and the pilot decides if it is a threat. The pilot then fires the missile, which attacks the target autonomously.
This wouldn't work with Ukrainian planes either as the missile can't

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transmit target data to the pilots.

BUT - most importantly: Self Protect and Target Of Opportunity modes are suicide UNLESS a plane carries a full range of jamming and self-protection pods. This is why the US nowadays only uses the AGM-88 with F-16CM and EA-18G planes.

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F-16CM carry an ALQ-184 ECM electronic countermeasures pod and at least one AN/ALE-50 towed decoy system.
EA-18G carry three AN/ALQ-99F(V) tactical jamming system pods (photo: one centerline and two under the wings).

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Without these systems planes will not survive flying high and deep into an enemy air-defense bubbles.

This leaves only the Pre-Briefed mode. In this mode a AGM-88 is programmed before the fighter departs from the air base with the coordinates of an enemy radar site.

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Once in the air the fighter releases the AGM-88 at maximum speed and maximum altitude, giving the missile a range in excess of 150 km.
Once released the AGM-88 will fly towards the coordinates, and when it reaches lock-on range it will scan for, detect, lock on and attack

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the target autonomously.

This mode works with Ukrainian fighters jets. All they have to do is lift the AGM-88 up, go supersonic, and release the missile.

While AGM-88B and AGM-88C-1 use INS to steer them towards a target area, where they then scan for targets, the

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AGM-88D also includes GPS-guidance, which enables the missile to strike known radar and air-defense sites, even when they do not emit radio frequencies.

And C-1 and D also have the ability to home-on-jam, which forces russia to switch off it's electronic warfare systems.

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And how does Ukraine know where to aim the AGM-88... I think there are two ways:

1) locals reporting the locations of russian air defense systems, radars, jammers, electronic warfare systems
2) US Air Force or UK Royal Air Force RC-135V/W Rivet Joint aircraft, which are

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used to detect, identify and geolocate electromagnetic signals.

US Air Force Rivet Joints have been used before to detected enemy radar and radio emissions and then vector AGM-88 carrying fighters towards these targets. However RC-135 flying over Romania can only scan the

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Kherson Oblast... anything further is out of range.

Ukraine using AGM-88 forces the russians to switch off all their systems emitting radio frequencies. If they leave them on 24/7 as they did until now Ukraine will destroy them all with AGM-88.

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And thanks to russia showing us the remnants of a AGM-88, we know that Ukraine received the D variant with GPS guidance.

So even if the russians switch their systems on and off, once the AGM-88D has locked on, there is no escape for the russians. Absolutely no escape.

16/end