July 17, 2018: On schedule the U.S. Marine Corps has selected a design for its new ACV 1.1 (Amphibious Combat Vehicle). There were five proposals offered in 2015 and the marines spent $240 million so the two finalists could each build sixteen of their vehicles for competitive testing that began in 2016.

The winning design was from European defense firm BAE and it is a variant of an existing vehicle; the SuperAV 6x6 used by the Brazilian Army as the VBTP-MR Guarani. The ACV version is an 8x8 vehicle weighing 31.5 tons and carrying 13 marines plus 3 crew. Other modifications the marines required included amphibious capability the use of lighter modular composite armor including ceramics, and have features that make them equal, if not better at resisting mine and IED explosions than MRAP (Mine Resistant Ambush Protected) vehicles using steel armor. ACV had an improved V shaped hull design with additional blast protection features for the floors as well as blast resistant seats attached to the troop compartment’s ceiling instead of the bottom of the vehicle’s hull. All these features had already been found, by trial and error in Iraq and Afghanistan, to greatly reduce casualties for vehicles attacked by landmines or roadside bombs.

The initial production contract is for 30 ACV 1.1 vehicles that will be delivered by late 2019 and most of the remaining 184 vehicles over the next few years. Each ACV 1.1 will cost about $5.9 million. The speed with which the ACV 1.2 modifications are implemented, to produce a better protected and more lethal ACV, are partly driven by how much the marines can afford to spend on the project.

As good as the ACV sounds this was not how it was supposed to be. In 2014 the marines revised its view of the future. Gone were the prospects of large (with hundreds or thousands of landing craft) amphibious operations that occurred in great numbers during World War II. The last operation of this type (Inchon, Korea) occurred in 1950, nearly 70 years ago. Now the marines expect to conduct raids, from ships up to 200 kilometers off shore. No amphibious armored vehicles could handle that, so landing tactics have to be changed. This resulted in major revisions to the specs for the new marine ACV amphibious armored vehicle.

The 2015 reality turned out to be different, and better. Given the prototypes offered and growing budget reductions it looked like the ACV 1.1 finalist would have the capability of moving from 20 kilometers off shore under its own power. To accomplish this the marines had to accept a vehicle that carried fewer marines and was somewhat less capable in the water. The AAV7 has 30 percent reserve buoyancy enabling it to cross 36 kilometers of water in sea state 5 at speeds of up to 12 kilometers an hour. The ACV 1.1 has 21 percent reserve buoyancy enabling it to cross 36 kilometers of water in sea state 3 at speeds of up to 11 kilometers an hour. On the plus side the ACV has wheels, not a track laying system and can do 105 kilometers an hour on roads versus 72 for the AAV7. In addition wheeled armored vehicles require far less maintenance that tracked ones (which need their tracks replaced far more frequently than wheels wear out.)

Meanwhile the marines refurbished the existing, 1970s era AAV7 amphibious armored vehicles to prolong service life until ACV can replace them. In addition to better protection the elderly AAV7s will be refurbished so they can remain in use until the mid-2020s. The marines never expected the AAV7s to last this long but several attempts to develop a replacement came up short. Thus the need to extend the life of their thousand AAV7 amphibious armored vehicles. These entered service in the 1970s and are falling apart. Moreover, some two thirds of the AAV7s saw service in Iraq, where they got as much use in two months as they normally did in two years of peacetime operations. Some 400 AAV7s are already scheduled for refurbishing, which begins this year and finishes in the early 2020s. Thus the AAV7s can still be used into the 2030s, or whenever the ACV are available in large enough numbers to replace them. With the acceptance of a final design for ACV 1.1 it looks like the AAV7s will be needed for about five more years.

The 29 ton AAV7s has a crew of four (driver, commander, gunner and rear crewman) and carries 25 combat ready marines as passengers. The vehicle is armed with a 40mm automatic grenade launcher and a 12.7mm machine-gun. When new their top land speed was 72 kilometers an hour on roads, 32 off road and 13 in water.

Back in 2011 the marines gave up on high-speed (sea skimming) amphibious assault vehicles. It then turned to a new ACV design to replace the AAV7s. DARPA (the Defense Advanced Research Projects Agency) was called in to help design the new vehicle. This may sound either very innovative or very desperate, and in reality it was both. In part because the marines had spent three billion dollars in an unsuccessful attempt (the EFV or Expeditionary Fighting Vehicle) to design and develop a high-speed amphibious vehicle and partly because that failure made it clear that some original thinking was required. In the end the ACV was the EFV without most of the expensive stuff that didn't work. In effect, the ACV was be a 21st century version of the AAV7, optimized to pass all its development tests and get into service as quickly as possible. DARPA quickly did its job but the resulting ACV was still more expensive ($12 million) than the shrinking marine budget could handle. The ACV design was tweaked until an affordable price was achieved.

In retrospect, the marines could have just built the EFV without the high-speed capability but that was eventually considered technically and politically impractical. The problem remains that the technology simply does not yet exist yet to make the high-speed capability workable. The budget situation is grim, leaving the usually unstoppable Marine Corps running into an immovable object and improvising as best they can. The marines had asked the navy to develop a high speed amphibious craft (or “connector”) to get ACVs to shore quickly but the navy budget is also shrinking and proved unable to handle the cost of developing and building the connector. Some marine analysts point out that the need for moving amphibious vehicles 200 kilometers from ship to shore is probably unrealistic for any likely future marine operations.