Ukraine received HARM anti-radar missiles from the US. How do HARM missiles work?

What is the HARM, and how does it work?

According to the Federation of American Scientists' Military Analysis Network, the AGM-88 HARM (high-speed antiradiation missile) is a supersonic air-to-surface tactical missile designed to seek and destroy enemy radar-equipped air defense systems. The AGM-88 can detect, attack, and destroy a target with minimum aircrew input. Guidance is provided through the reception of signals emitted from a ground-based threat radar. It has the capability of discriminating a single target from a number of emitters in the environment.

The proportional guidance system that homes in on enemy radar emissions has a fixed antenna and seeker head in the missile nose. A smokeless, solid-propellant, dual-thrust rocket motor propels the missile. The Navy and Marine Corps F/A-18 and EA-6B can employ the AGM-88. With the retirement of the F-4, the F-16C is the only aircraft in the current Air Force inventory to use the AGM-88. The B version has an improved guidance section incorporating improved tactical software and electronically reprogrammable memory.

These Raytheon-made missiles have a range of more than 30 miles (48km), making them one of the longer-range weapons the U.S. has yet supplied to Ukraine.

The Russian anti-aircraft radar systems, such as the S-400, have made it very challenging for the Ukrainian Air Force to fly over substantial portions of Ukrainian airspace, and the missiles can be employed to target these systems.

Additionally, the missiles can hit Russian counter-battery radars, which Russia employs to attack Ukrainian artillery.

Kahl said the missiles had been sent over "in recent [Presidential Drawdown Authority] packages." However, according to CNN, the five most recent packages, dating back to the 1st of July 2022, make no mention of HARMs.

The anti-missile systems should help Ukraine maintain what remains of its air force

"In the near term, we've been doing lots of things to make Ukraine's existing air force stay in the air and be more capable," Kahl explained.

He indicated the Mig-29 fighter jet replacement parts that the U.S. had assisted in delivering to Ukraine so that the aircraft could continue to operate. The missiles were then brought up by Kahl, who stated that they "can have effects on Russian radars and other things."

It is important to note the Ukrainians have not publicly acknowledged the use or receipt of HARMs.

The remains of what appears to be the fin of a HARM missile that was aimed at a Russian site in Ukraine have been depicted in open source accounts, however.

In a briefing about the Pentagon's most recent $1 billion arms package for Ukraine—the largest U.S. weapons package to date—Kahl revealed the missiles.

The main goal of the package was to provide ammunition for some of the important weapon systems that the U.S. supplied to Ukraine. That includes 777 howitzers, which have been a crucial weapon in the conflict in the Donbas region of eastern Ukraine, as well as the High-Mobility Artillery Rocket System (HIMARS), which the Ukrainian military has utilized to effectively target Russian command posts, ammunition depots, and more.

According to Kahl, thus far in the battle, Russia has suffered between 70,000 and 80,000 war losses, including dead and injured in action.

"That number might be a little lower, a little higher, but I think that's kind of in the ballpark," he said. He also added that Russia has lost between 3,000-4,000 armored vehicles.

With this latest package, the U.S. has committed to sending Ukraine a total of $9.1 billion in security assistance since the beginning of Russia's invasion in late February of 2022.