The U.S. Marine Corps has stopped sending its new amphibious combat vehicles into the water while it investigates a disastrous training exercise that took place Tuesday. Two of the tank-like machines ran into trouble off the coast of Southern California in unusually high waves caused by a storm in the southern hemisphere. One of the vehicles rolled over in the surf, though thankfully no troops were injured. Another was left completely disabled in the choppy eight-foot swells. Personnel involved in the accident had to swim to shore at Marine Corps Base Camp Pendleton around 20 miles north of San Diego. The new amphibious vehicles had been brought in to replace Vietnam War-era hardware that had been involved in a 2020 sinking that left eight Marines and one sailor dead.