The Marine Corps plans to test its first Stern Landing Vessel (SLV) early next year as it develops the needs for the new Landing Ship Medium (LSM) to be bought in two years, a top service official said this week.

The service contracted with Hornbeck Offshore Services

(HOS) to lease a modified Offshore Support Vessel converted into an SLV as part of the service’s bridging plan to refine the requirements for the LSM and fill the hole of the capability until the LSMs are delivered.

Concept image for the Marine Corps Landing Ship Medium (LSM), previously called the Light Amphibious Warship (LAW). (Image: artist concept, screen shot from a Marine Corps Combat Development & Integration Youtube video)
Concept image for the Marine Corps Landing Ship Medium (LSM), previously called the Light Amphibious Warship (LAW). (Image: artist concept, screen shot from a Marine Corps Combat Development & Integration Youtube video)

During the Defense News Conference on Sept. 6, Lt. Gen. Karsten Heckl, deputy commandant of the Marine Corps for combat development and integration, said the service will test the first SLV prototype at the Army’s Project Convergence Capstone 4 event, set for February/March 2024.

The Marine Corps plans to lease each SLV for several years, but the contracts include options for the government to later buy them outright. The service has plans to lease upward of three SLVs.

In March, a service official outlined how the Marine Corps Warfighting Lab plans to experiment with SLV-1, starting with a 12-week initial test period and ultimately culminating with integrating the vessel with MLR and fleet usage and then joint operations (Defense Daily, March 6).

At the time, the official said the Marine Corps expects to receive SLV-2 and -3 in 2024 via the normal contracting process with Military Sealift Command. 

Heckl said he was impressed with the first one and SLV-2 may include more of a purpose-built SLV with changes.

“When I saw SLV number one it was amazing what industry did. I mean quick, really quick, really impressive.”

The first SLV has a 12-foot draft, 6,000 square feet of cargo space, the ability to hold 38 Marines as well as up to 15 commercial mariners, a large ramp, landing skegs, and landing legs.

Heckl said the service has gone through Foreign Comparative Tests (FCT) for Australian company Sea Transport to possibly provide LSV-3. He argued the company is well positioned to provide a capability for use in the Indo-Pacific, which may produce SLV-3 for the Marine Corps. 

“I’ve met with them a couple of times, an Australian company that knows the Indo-Pacific really, really well, and knows how to operate in the Indo-Pacific really, really well. So we’re excited about that as well.”

Speaking to reporters after his remarks on-stage, Heckl said Sea Transport “gave an impressive pitch to me. I have a pretty good poker face but it was like ‘Wow, pretty good stuff.’…it’s a company that lives in the Indo-Pacific, they know the area, they know the needs and requirements, they’ve built these before. So we’re excited. And again we’re…casting the net as widely as possible.”

The Marine Corps aims to have an initial capability of 18 LSMs, although it wants up to 35 total, but that latter figure could include a mix of other similar craft (Defense Daily, Jan. 17).

The LSMs will carry about 75 Marines each, so nine can field one of three planned Marine Littoral Regiments. The service is seeking 35 vessels to account for maintenance schedules.

Graphic rendering of the Marine Corps’ first Stern Landing Vessel (SLV), HOS Resolution, a modified Hornbeck Offshore Services Offshore Support Vessel. The SLVwill be used for testing Landing Ship Medium concepts. (Image: U.S. Marine Corps)
Graphic rendering of the Marine Corps’ first Stern Landing Vessel (SLV), HOS Resolution, a modified Hornbeck Offshore Services Offshore Support Vessel. The SLV will be used for testing Landing Ship Medium concepts. (Image: U.S. Marine Corps)

Documents in the Navy’s fiscal year 2024 budget request show plans for the Marine Corps to buy up to six LSMs by 2028 (Defense Daily, March 13).

The Marine Corps is also looking at testing and using Expeditionary Transfer Dock ships (ESB), Spearhead-class Expeditionary Fast Transport ships (T-EPF) and Landing Craft Utility (LCU) vessels in addition to the SLVs as part of the bridging solution until the LSMs are ready. 

He noted Marine Corps forces in the U.S. Sixth Fleet have recently been “playing with the ESBs, so I think there’s a lot of options out there.”

The bridging solutions may ultimately help bulk up the LSM fleet, to push past the base requirement of 18 LSMs to the Marine Corps’ 35 vessel needs.

Separately, Heckl confirmed the service is working with five competitors that are developing prototypes for the LSM and the Marine Corps will down-select from them. 

He admitted the LSM schedule has been pushed forward to start finding in 2025, but argued this is allowing them to get the vessel requirements right.

“Yes, things have slipped right, I think for all the right reasons. We’re just simply trying to get the requirements right, while still trying to do move at pace, because if you start moving too quickly, you might end up jumping to a conclusion that you probably should have taken a little more time to look at…I think we’re going to get the exact right thing,” Heckl said during the event.

Australia’s Sea Transport Solutions’ stern landing vessel design concept. (Image: Sea Transport Solutions)
Australia’s Sea Transport Solutions’ stern landing vessel design concept. (Image: Sea Transport Solutions)

He noted LSM needs to be a cost-effective vessel that will primarily be used for deterrence and cooperation with allies and partners.

“This is going to be primarily, 99 percent of the time, a deterrence tool. It’s going to be a day-to-day competition, working with allies and partners. So we are trying to find the most cost effective way and prudent expenditure of the taxpayers’ money.”

Documents from a May Request For Information seeking industrial sources interested in the detail design and construction (DD&C) of the LSM said the Navy was interested in ultimately procuring four LSMs per year while working from a parent design (Defense Daily, May 23).

Heckl said 70 percent of the vision for LSM has been unchanged since it was originally outlined in the Marine Corps Force Design 2030 document from 2020, with the core design remaining the same.

“I think the emphasis now – to really get to operate inside of the weapons engagement zone of [China] it needs to be focused on –  we need a shore-to-shore connector. So a beachable [craft], that has the gradient to be able to beach itself in the vast majority of the littorals of the Indo-Pacific. That way, I’m not relying on an airfield that can be easily damaged.”

He confirmed he is “pretty confident” LSM will be on contract on schedule by FY 2025.