- The Marine Corps released the investigation into the AAV that sank and killed nine last summer.
- Research shows that failure after failure has led to tragedy.
- At one point, soldiers used phones to open the escape hatch because the emergency lights were off.
- See more stories on the Insider business page.
The US Marine Corps (AMAV) assault vehicle accident last summer, which killed nine soldiers, was a disaster in which failure after failure led to tragedy, a newly released investigation revealed.
Many things have gone wrong. At one point, just minutes before the vehicle sank, the troops on board were using their cell phones as flashlights to try to open one of the escape hatches because the emergency lighting system was not working. This was just one of the many problems encountered by the investigation.
An AAV is a fully tracked heavy amphibious landing vehicle, commonly known as “amtrac” or “runway”, which carries up to two dozen soldiers between ships at sea and on the coast.
Last July, an AAV assigned to the Bravo Company, Battalion Landing Team 1st Battalion, 4th Marines, part of the 15th Marine Expeditionary Expeditionary Unit, sank off the California coast as it returned to the USS Somerset amphibious transport pier on San Clemente Island .
The accident carried three AAV crew members, 12 Marines and a Navy officer. Eight Marines on board and the Navy sailor died, making this incident the deadliest AAV training accident in the vehicle’s history.
Subsequently, the Marine Corps suspended its entire fleet of AAVs by launching an investigation into what exactly happened. Maritime operations have not yet resumed.
The US Marine Corps Pacific commander blamed the sinking and deaths resulting in “a confluence of human and mechanical failures” in a statement attached to the investigation. He added that “this tragic accident was preventable.”
Marines board an amphibious assault vehicle.
US Army National Guard photo by Cpl. Katharine Silent Water
‘Human and mechanical failures’
The command’s investigation found that the accident was caused by maintenance failures, delays in evacuation orders and failure to properly train personnel on board AAV security procedures, among other problems.
When the 26-ton amphibious vehicle returned to Somerset after an exercise on land on July 30, water was leaking into the hull of the AAV from various locations. All AAVs leak, but more water was leaking than normal due to several maintenance failures.
At around 5:30 pm local time, the aft crew member informed the vehicle commander that the water inside the AAV had reached the deck plate. The commander would have replied, “Thanks for letting me know.”
The standard operating procedure is for personnel on board to prepare for water operations when the water reaches the deck plate. Evacuation should begin when the water reaches the level of the boot’s ankle, but it did not and the results were fatal.
In addition to several leakage integrity failures, the vehicle also suffered several other serious mechanical failures, from the transmission to the generator, which impacted the four sewage pumps in place to push the water out of the vehicle. The communication system was also affected.
When the water reached the level of the boot’s ankle, the commander of the vehicle started waving the November flag, a blue and white flag signaling that a watercraft is in danger and needs immediate assistance, but no evacuation orders have been given, said the investigation.
As for the boarded personnel who were traveling in the back, the investigation said they “were not properly trained and did not realize how dire the situation was … when the water was at the ankle of the boot”.
Not only did they not receive adequate safety instructions before maritime operations, but the investigation also found that many of the soldiers on board had not completed the necessary training on how to get out of the vehicle in an emergency.
The commander waved the blue and white distress flag for 20 minutes, but did not make use of the available pyrotechnic signaling options.
Due to a communication failure, there were no safety boats or support AAVs in the water at the time of the accident, although two other AAVs maneuvered to help.
By 6:05 pm, the water in the AAV was almost at the calf and the rear crew member recommended evacuation to the vehicle commander. The order to open the starboard cargo hatch and start the evacuation did not come until the water reached the benches.
The troops in the back moved to open the cargo hatch at the top, but things did not go well due to the lack of training and reduced visibility. It was “extremely dark” inside the AAV.
The command’s investigation said that “personnel on board were using cell phones as a source of illumination due to the non-functioning of the Emergency Exit Lighting System and the fact that no chemical light was used to mark the hatch handles.” EELS had been inexplicably disabled.
By the time they opened the hatch and started taking people out, the AAV was just 15 centimeters from the water, which made him extremely vulnerable. To make matters worse, an auxiliary AAV collided with the accident vehicle, knocking it aside.
When a wave hit the struggling AAV, water entered the open hatch, flooding the vehicle.
Some soldiers were standing on the benches along the interior of the vehicle when “the force of running water knocked over all the personnel”, leaving the soldiers shocked and disoriented, the investigation said.
Minutes later, around 6:15 pm, the vehicle, which had been slowly sinking for about 45 minutes, tilted and slid down the surface, falling to a depth of 385 feet.
All but one soldier managed to get out of the AAV, but seven soldiers who managed to escape drowned before reaching the surface. A military man made it to the surface, but died of drowning.
The command’s investigation said that all deceased military personnel were wearing bulletproof vests. Some troops appear to have tried to remove their equipment, but the life jacket has negatively impacted those efforts.
For those who never made it to the surface, lifeguards were less effective in depth, especially due to the excess weight the troops carried.
The soldiers who died when their vehicle sank last summer were Lance Cpl. Guillermo Perez, Pfc. Bryan Baltierra, Lance Cpl. Marco Barranco, Pfc. Evan Bath, Pfc. Jack Ryan Ostrovsky, Cpl. Wesley Rodd, Lance Cpl. Chase Sweetwood and Cpl. Cesar Villanueva and Hospitalman Christopher Gnem.
The Marine Corps said in a statement on Thursday that its loss continues to be felt throughout the service.
Marines aboard an amphibious assault vehicle prepare for an amphibious assault.
US Army National Guard photo by Spc. Emily Eppens
‘A tragic accident was preventable’
The commander of the Marine Expeditionary Force said in a statement that “this whole accident could have been prevented and lives saved if the commander of the vehicle had followed [standard operating procedures] and ordered the onboard personnel to remove their equipment and evacuate the AAV accident at the appropriate time. “
But, there were also problems at other levels. He noted that, at the platoon level, “discipline and combat effectiveness were seriously compromised.”
The Marine Corps has already removed senior commanders from the 1st BLT Battalion, 4th Marines and 15th MEU. The commander of the Bravo Company was also fired. Unspecified disciplinary action has also been recommended for some others in the chain of command.
In the wake of the deadly accident last summer, the Corps adjusted the inspection standards for its AAVs. He also halted all AAV maritime operations until the entire fleet of about 800 vehicles could be inspected. The investigation said that “most AAVs did not meet the new inspection criteria.”
The AAV that sank and killed eight Marines and a sailor was not the only vehicle that encountered problems during last summer’s training exercise.
A little more than a dozen AAVs were involved in the training. One had to be left on the ship because it was inoperable, another had to be picked up on San Clemente Island by a Landing Craft aerial cushion after the malfunction, and one lost maneuverability and had to be towed back to the island .
An inspection of participating vehicles after the accident found that most were in “poor condition”.
A veteran of the Navy Insider spoke earlier about the problems with AAVs, said the vehicles “are deadly traps and need to be updated, if not completely eradicated from the Marine Corps.”
Marine Corps officers insist that vehicles are safe, provided the procedures are properly followed.
The Corps is in the process of eliminating its AAVs and replacing them with the new Amphibious Combat Vehicle (ACV). The service is also making dozens of changes to the way it maintains and operates amphibious vehicles to ensure that nothing like what happened last summer happens again.