A Marine attack helicopter struck and sank a mock ship in the Pacific last week using a new air-to-ground missile, the service said Friday.

An AH-1Z Viper crew attached to Marine Medium Tiltrotor Squadron 262 fired the live missile in the Philippine Sea near Okinawa on Wednesday as a vessel towed a mock ship, sinking it into the ocean.

The missile, which has been in development for years, is called the AGM-179 Joint Air-to-Ground Missile, or JAGM, and is meant to be used by helicopters, drones and fixed-wing platforms to “destroy high-value, stationary and moving, land and maritime targets,” according to the Navy.

According to the Marine Corps, the first successful live-fire of the missile proved to be a boon for the service’s ability to defend maritime terrain as it continues to reorganize itself for a fight in the Pacific. And it was the first use of the live ordnance in the Pacific.

“The success of this expeditionary strike demonstrates the 31st MEU’s capability to deliver precision strikes at sea and safeguard a free and open Indo-Pacific,” Capt. Pawel Puczko, director of the 31st Marine Expeditionary Unit’s communications office, said in the press release announcing the successful test on Friday.

The JAGM replaced the legendary Hellfire missile, which saw decades of service in the military at a reliability rate of 97%, according to Lockheed Martin, which developed both ordnance. Using sensors and radar, the JAGM was approved for full production in 2022 and can also be used on Army AH-64E Apache helicopters.

In Wednesday’s demonstration, the Viper was accompanied by a UH-1Y Huey during a forward arming and refueling operation, or FARP, which resupplies and rearms the aircraft at various objectives — a necessity for Marine expeditionary units looking to embark on long-range missions in the vast Pacific region.

“There it goes, cool,” one of the operators said as the Viper launched the JAGM last week, according to a video posted on the Defense Visual Information Distribution Service, or DVIDS. The mock vessel exploded, fragments flying, as it sank into the ocean.

“Direct hit,” the operator said. Helicopter door gunners in what appeared to be the Huey then strafed another target moving in the water.

The missile failed to achieve its desired effects on a target in 2020, according to Defense News. Since then, the services and Lockheed have worked to improve the missile, including by extending its original range of five miles to nearly 10 in 2022.