The U.S. Marine Corps is upgrading its 1970s era AAV7 amphibious armored vehicles. In addition to better protection the elderly AAV7s will be refurbished so they can remain in service another decade or more. The marines never expected the AAV7s to last this long but several attempts to develop a replacement have come 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 will begin in 2018 and complete in the early 2020. Thus the AAV7s can still be used into the 2030s, or whenever a permanent replacement can be found.
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. Top land speed is 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 Amphibious Combat vehicle (ACV) 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 recently blew 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. The $12 million 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 marines have another replacement vehicle projects as well. The MPC (Marine Personnel Carrier) is a $4.5 million wheeled, amphibious armored vehicle. This would be similar to the Stryker but a bit larger and modified for amphibious operations. This project is proceeding because it is low-risk (in the technology department) and the marines need some kind of armored vehicle to replace AAV7s that are dying of old age. The marines do not want to be reminded of the EFV. But they cannot afford the ACV and the MPC, while affordable, is not as amphibious as the AAV7. The marines apparently felt they could get by with half as many new amphibious armored vehicles because future wars are likely to be more dependent on delivering troops by air or moving them around in armored hummers. While there was some thought of dispensing entirely with vehicles like this, which were first used in 1943, more traditionalist minds prevailed. That may change, especially since the cheaper MPC is more likely to survive the budget battles than the ACV.
In retrospect, the marines could have just built the EFV without the high-speed capability but too late they discovered that the technology simply did not 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 have asked the navy to develop a high speed amphibious craft (or “connector”) to get MPCs to shore quickly but the navy budget is also shrinking and probably unable to handle the cost of developing and building the connector.