Dawn Blitz, as a whole, is an annual amphibious warfare drill that runs Marines, sailors, and other U.S. military forces through scenarios based on potential global emergencies. Prepositioned Marine expeditionary units embarked on Navy amphibious ships remain one of America’s primary means of quickly responding to a crisis of any kind, including natural disasters.

"We had two training objectives for today's shoot," U.S. Army Major Adam Ropelewski, the lead planner attached to I Marine Expeditionary Force for what the exercise organizers termed “sea-based expeditionary fires,” explained. “The first training objective was demonstrating this capability and, second, we wanted to have good effects on the target. We achieved both objectives.”

Marines of the 5th Marine Battalion, 11th Marine Regiment conducted the mock fire support mission with a truck-mounted M142 High Mobility Artillery Rocket System (HIMARS) while on board the USS Anchorage, a San Antonio-class landing platform dock. The 227mm M31 Guided Multiple Launch Rocket System (GLMRS) round hit a target floating in the Pacific Ocean with its 200 pound high explosive warhead approximately 43 miles away, the maximum range of the weapon.

As it had long planned, the U.S. Marine Corps has successfully fired a 227mm GPS-guided rocket from the flight deck of a ship during an annual exercise in the Pacific region, nicknamed Dawn Blitz 2017. Something we at The War Zone have highlighted many times in the past, this combination could offer an important new capability for traditional amphibious operations, more limited contingencies, and even possibly operations further out at sea.

HIMARS, in particular, makes a lot of sense for sea-based operations. The wheeled launcher can either hold six 227mm rockets or a single, larger short-range ballistic missile, known as the Army Tactical Missile System (ATACMS) inside a standardized rocket pod that makes the whole system relatively easy to reload. With that latter weapon, crews can hit targets approximately 190 miles away.

“You’re not going to see Marines just sitting down on their bunks reading magazines,” Neller said at the Marine Corps League’s annual Modern Day Marine exposition in September 2017. “You’re going to see snipers up on the weather deck. You’re going to see guys up there with Javelins and heavy guns. You’re going to see air defenders up there with air defense systems .”

But Marines using of artillery rockets and other weapons while still on board a ship is definitely something that the service has been considering for some time. Since taking up the post of Commandant in 2015, U.S. Marine Corps General Robert Neller has been vocal about challenging established notions about the way his troops operate.

The sea-based HIMARS launch was one of a number of firsts for the event. This is also the first year that the Marine Corps’ F-35B Joint Strike Fighters have joined the exercise.

“Dawn Blitz 2017 is an excellent opportunity to operationalize concepts the Navy and Marine Corps services have been discussing for some time,” Navy Commander Matthew Hoekstra, the lead exercise planner, said . “While others continue to talk, wargame or tabletop future concepts, we are executing with live forces afloat and ashore.”

For the 2017 iteration of the exercise, Marines from the I Marine Expeditionary Force have joined forces with the Anchorage, as well as the amphibious assault ship USS Essex, the landing ship dock USS Rushmore, and the Arleigh Burke-class destroyer USS Wayne E. Meyer, as well as small patrol boats from Coastal Riverine Group One. Members of the U.S. Army are also involved or otherwise present to observe, as are foreign allies. Most notably, an infantry company from Japan’s Ground Self-Defense Force its taking part in the drill.

It’s already been a major factor in the U.S.-led campaign against ISIS in Iraq and Syria, where the weapons offered an alternative to air strikes to launch precision strikes against terrorist emplacements. Unlike fixed wing combat aircraft or gunship helicopters, HIMARS doesn't get grounded due to sandstorms or low overcast skies. Depending on whether or not there are already aircraft on station, artillery, including the guided rockets, responds to requests for support much faster. These benefits had already made it a weapon of choice in Afghanistan, including for targeted strikes against particular militants. With these weapons on amphibious ships sitting off shore, Marines would be able to have on-call, precision artillery fire during an amphibious landing without having the launchers at increased risk on the beachhead itself or relying mainly on aircraft or attack helicopters for this type of support. Once the initial landing area is secure, the trucks can go ashore and continue to support the force as it moves further inland, complimenting air support carriers and amphibious assault ships. “We know we can shoot HIMARS [High Mobility Artillery Rocket System] off the flight deck of a ship,” Neller added at the Modern Day Marine exposition. “You’re going to see precision fire delivered off amphib ships, whether it comes out of tube guns or rockets or delivered from unmanned systems.”

USMC A HIMARS crew from 5/11th Marines reloads their launcher during an exercise in 2014.

Even the basic 227mm GPS-directed rockets would give amphibious ships significantly more stand-off capability than they have at present. The design for the San Antonio-class included space for two Mk 41 eight-cell vertical launch system (VLS), but the ships did not reach the fleet with those weapons in place. Whidbey Island-class landing ship docks and Wasp- and America-class amphibious assault ships do not have any such provisions at all. In December 2016, Neller had brought up the possibility of adding the VLS cells onto the San Antonio’s in order to let them carry Tomahawk land attack cruise missiles. He pointed to a series of attacks off the coast of Yemen that year in which Iranian-backed Houthi rebels had fired anti-ship missiles at American naval vessels, including the San Antonio herself. The amphibious ship lacked the means to retaliate directly. However, the original plan had been to pack the San Antonio’s VLS full of RIM-162 Evolved Sea Sparrow Missiles (ESSM), four of which can fit in each cell, in order to expand the air defense capabilities of an amphibious expeditionary strike group. Each cell could only have accommodated a single Tomahawk. The War Zone's own Tyler Rogoway has previously argued that adding the VLS capability in would be a major boon to the ships and also noted that it might even make more sense to just use that space for fixed GMLRS rocket pods to begin with, something that would make sense on other surface ships, too. With HIMARS launchers on the deck, the ship would have had another, potentially more flexible means to respond to multiple threats. A Marine artillery crew would be able to reload much faster than sailors would be able to insert new missiles into the VLS for follow up with additional strikes if more targets presented themselves, as well. The Marine Corps is also looking at a concept that would move the rocket launcher into a containerized package, dubbed "Box O'Rockets," that would be easy to mount on standard cargo trucks or any appropriate flat surface on a ship or on land.

USMC Concept art of Box O'Rockets on a notional modular floating platform.