{"id":18768,"date":"2021-04-16T02:49:39","date_gmt":"2021-04-16T02:49:39","guid":{"rendered":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/uncategorized\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/"},"modified":"2026-08-08T20:15:18","modified_gmt":"2026-08-08T20:15:18","slug":"what-caused-the-marine-amphibious-assault-sinking-tragedy","status":"publish","type":"post","link":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/","title":{"rendered":"What caused the Marine amphibious assault vehicle sinking tragedy?"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u201cIt\u2019s alright, just calm down \u2014 we\u2019re going to make it back to the ship. Just do me a favor and take a deep breath.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">These were the words a Marine told his <a href=\"https:\/\/www.marinecorpstimes.com\/news\/your-marine-corps\/2021\/03\/31\/its-your-date-of-death-just-finish-this-mission-families-of-fallen-marines-sailor-react-to-investigation-of-tragic-aav-sinking\/\" target=_blank>\u00adamphibious assault vehicle<\/a> rear crewman on July 30, 2020, as reality hit that the AAV they were in was actually sinking.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The water was up to top-of-the-boot level at that point, and the Marines and sailor trapped inside were nervous.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The platoon had been finishing a training raid and was coming from San Clemente Island, California.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Before the mission had even started that \u00admorning another AAV had been pulled for <a href=\"https:\/\/www.marinecorpstimes.com\/news\/your-marine-corps\/2021\/03\/25\/the-marine-corps-amphibious-assault-vehicle-that-sank-and-killed-9-should-never-have-left-the-motor-pool-slides-into-investigation-show\/\" target=_blank>maintenance issues<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">By the end of the mission four out of the 13 AAVs assigned to the 15th Marine Expeditionary Unit had broken down.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">And, by the end of the day, the AAV these \u00adMarines and sailor were in would never make it back to the ship nor the shore.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Catastrophic failures<a href=\"https:\/\/www.marinecorpstimes.com\/news\/your-marine-corps\/2021\/04\/13\/marine-commandant-called-to-testify-on-safety-after-9-deaths-in-amphibious-assault-vehicle\/\" target=_blank> led to its sinking<\/a>, resulting in the deaths of eight Marines and one sailor.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Their deaths were the result of a series of failures, the 2,002 page Marine Corps investigation into the accident found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Failures that day included the choice to use previously deadlined vehicles, the failure to notice significant mechanical issues with the AAV that sank, the failure to properly train the Marines and sailor who died, and the repeated failure to follow standard operating procedures during the exercise, the command investigation found.<\/p>\n\n\n\t<aside class=\"smg-interstitial-link wp-block-smg-interstitial-link\">\n\t\t<a href=\"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/03\/31\/its-your-date-of-death-just-finish-this-mission-families-of-fallen-marines-sailor-react-to-investigation-of-tragic-aav-sinking\/\" class=\"smg-interstitial-link__inner\">\n\t\t\t\t\t\t\t<div class=\"smg-interstitial-link__media\">\n\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"165\" src=\"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/B200812-M-JX780-1239.jpg.jpg?w=300\" class=\"smg-interstitial-link__image wp-post-image\" alt=\"\" \/>\t\t\t\t<\/div>\n\t\t\t\t\t\t<div class=\"smg-interstitial-link__content\">\n\t\t\t\t<span class=\"smg-interstitial-link__kicker\">Related<\/span>\n\t\t\t\t<h3 class=\"smg-interstitial-link__title\">\u2018It\u2019s your date of death, just finish this mission\u2019: Heartbroken families of fallen Marines, sailor react to failures exposed in tragic AAV sinking investigation<\/h3>\n\t\t\t\t\t\t\t\t\t<p class=\"smg-interstitial-link__excerpt\">Anger, disgust and unimaginable grief were some of the words used to describe the emotions felt by some of the families of the nine service members who didn\u2019t survive that day.<\/p>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/a>\n\t<\/aside>\n\t\n\n\n<p class=\"wp-block-paragraph\">The vehicle that sank that day was 36 years old \u2014 more than 14 years older than the oldest Marine killed in the accident. They were Pfc. Bryan J. Baltierra, 18, of Corona, California, a rifleman. Lance Cpl. Marco A. Barranco, 21, of Montebello, California, a rifleman. Pfc. Evan A. Bath, 19, of Oak Creek, Wisconsin, a rifleman. U.S. Navy Hospitalman Christopher Gnem, 22, of Stockton, California, a hospital corpsman. Pfc. Jack Ryan Ostrovsky, 20, of Bend, Oregon, a rifleman. Cpl. Wesley A. Rodd, 22, of Harris, Texas, a rifleman. Lance Cpl. Chase D. Sweetwood, 18, of Portland, Oregon, a rifleman. Cpl. Cesar A. \u00adVillanueva, 21, of Riverside, California, a rifleman. And Lance Cpl. Guillermo S. Perez, 19,  of New Braunfels, Texas, a rifleman.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Marines and sailor who died were all \u00adassigned to Battalion Landing Team 1\/4.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cThe investigation reveals a confluence of human and mechanical failures caused the sinking \u2026 and contributed to a delayed rescue effort,\u201d Lt. Gen. Steven Rudder, commander of Marine Forces Pacific, said in the investigation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cUltimately, this tragic mishap was preventable,\u201d he said.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><b>Mechanical problems<\/b><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">On the day of the incident the vehicle that sank ran into its first mechanical problem while still on the beach of San Clemente Island, California.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It was there on the beach that the AAV crew had discovered oil leaking out of the engine. They eventually added six gallons of oil to the \u00adtransmission, roughly a quarter of the 23 gallons required for it to operate correctly.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cDuring the time we were on the island I remember &#8230; the driver had mentioned that his transmission oil was running low,\u201d the rear \u00adcrewman in the AAV that day told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The rear crewman, whose name was redacted from the investigation, normally was an AAV mechanic, but was assigned to the AAV that day because the usual rear crewman had tested positive for COVID-19.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">After refilling the vehicle with oil, the crew set off on its return trip to the Somerset, according to the investigation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">No safety boat was in the water that day.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In the morning the safety boat offered by the crew of the Somerset had mechanical issues and was unable to deploy. But, because AAVs can operate as safety boats when no other vehicle is available, the platoon commander designated one of the AAVs as the safety boat for the trip to shore. Though one AAV was designated, two were required by the standard operating procedures \u2014one of the first violations of the day.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For the return trip the commander said he assumed the Navy would be providing safety boats and did not designate any of the vehicles as a \u00adsafety boat, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">As the AAVs headed out to sea they started to experience rougher waters than were permitted by mission\u2019s no-go standards.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cAs soon as we splashed again you knew almost immediately that the sea state was worse,\u201d one of the Marines on the AAV told investigators. \u201cWe were rocking back and forth really hard. We were getting so much water through the hatches on top that I thought it was raining.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Prior to any exercise, AAV leadership is supposed to observe the water to ensure Marines are not operating in unsafe conditions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The last sea state observation that day took place around 12:23 p.m., more than four hours before the AAVs headed back to the Somerset. Though there is no definitive evidence, it is suspected that the sea state \u201cexceeded the no-go decision criteria,\u201d the investigation found.<\/p>\n\n\n<figure class=\"wp-block-smg-jwplayer-video\"><atype-video-jwplayer nostick=\"true\" playlisturl=\"https:\/\/cdn.jwplayer.com\/v2\/playlists\/fCzRqMW8?tags=8c690af7-1852-4411-a3cd-ab2a7a9dbe73\" poster=\"\/wp-content\/uploads\/2026\/08\/video-poster-8c690af7-1852-4411-a3cd-ab2a7a9dbe73.jpg\" aspectratio=\"16 \/ 9\" mute autostart=\"false\"><\/atype-video-jwplayer><figcaption class=\"wp-element-caption\">A report reveals the details of the deadly AAV sinking that killed eight Marines and a sailor least year in a training incident off the California coast.<\/figcaption><\/figure>\n\n\n<p class=\"wp-block-paragraph\">Around 5:30 p.m. the rear AAV crewman in the vehicle that ended up sinking notified the vehicle commander that they were taking on water.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cThanks for letting me know,\u201d the commander said while continuing the trip back to the Somerset.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The water already was high enough that the \u00adMarines should have started preparing to evacuate, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But the vehicle commander told investigators he was not worried about the excess water because at that time the bilge pumps were working and he assumed the excess water came from waves hitting the AAV, not from any internal leak.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cThere was some water in the back, which I was sure was from all the waves that we ate,\u201d the vehicle commander told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Inspection of the vehicle after the incident found several points where water had leaked into the vehicle, including through an improperly installed headlight and the intake and exhaust plenum grills.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The investigation also found the vehicle had \u00adpractically no oil in the transmission.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Shortly after taking on water the voltage in the AAV started to drop, reducing the vehicle\u2019s radio output and preventing the bilge pumps from dumping water out of the AAV fast enough.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Eventually the transmission, low on oil, failed, triggering a chain of events that caused the vehicle to sink, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The transmission failure sent the engine into an idle, which caused the vehicle to stop in the water.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That loss of forward momentum prevented the \u00adforward hydraulic bilge pump from dispelling water. The rising water level in the engine led to water hitting the generator, causing the generator to fail, \u00adeventually leaving the remaining bilge pumps \u00adoperating at a degraded level.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When the rear crewman told the vehicle \u00adcommander that the water inside the vehicle had reached ankle level, the commander started waving the \u201cNovember\u201d flag, indicating that the vehicle was at risk of sinking. The AAV\u2019s radio was not working.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cThe next time I spoke to (the vehicle commander) was when the water was at boot top level,\u201d the rear crewman told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI remember screaming up to (the vehicle commander) water is at boot top, we need to start \u00adthinking about getting these guys out of here.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But the Marine did not give the command to evacuate, as required by the standard operating procedure.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Rudder said the lack of safety boats left the vehicle commander with no good options.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI concur that the order to remove personal equipment and prepare for troop transfer should have been given by the mishap AAV commander,\u201d Rudder said.<\/p>\n\n\n\t<aside class=\"smg-interstitial-link wp-block-smg-interstitial-link\">\n\t\t<a href=\"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/13\/marine-commandant-called-to-testify-on-safety-after-9-deaths-in-amphibious-assault-vehicle\/\" class=\"smg-interstitial-link__inner\">\n\t\t\t\t\t\t\t<div class=\"smg-interstitial-link__media\">\n\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"179\" src=\"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/200326-D-BN624-0055.jpg.jpg?w=300\" class=\"smg-interstitial-link__image wp-post-image\" alt=\"\" \/>\t\t\t\t<\/div>\n\t\t\t\t\t\t<div class=\"smg-interstitial-link__content\">\n\t\t\t\t<span class=\"smg-interstitial-link__kicker\">Related<\/span>\n\t\t\t\t<h3 class=\"smg-interstitial-link__title\">Top Marine called to testify on 9 deaths in amphibious assault vehicle accident<\/h3>\n\t\t\t\t\t\t\t\t\t<p class=\"smg-interstitial-link__excerpt\">The Corps\u2019 safety issues go well beyond this one accident, one congressman said.<\/p>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/a>\n\t<\/aside>\n\t\n\n\n<p class=\"wp-block-paragraph\">But the SOP does not account for \u201ca circumstance in which the AAV is in a rough sea state, no safety boats are in the water and the AAV is slowly sinking,\u201d Rudder said.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The vehicle commander told investigators, \u201cI just kept telling him (the rear crewman) to stay calm and that we had to get to the ship.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">One of the survivors later said that it was around this time that the crew of the AAV started to get nervous.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI began to notice that the crew was getting concerned. I could tell the (rear crewman) was freaking out still.\u2019\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">After roughly 20 minutes of waving the November flag, two nearby AAVs finally noticed and started to slowly move toward the sinking AAV.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When the water inside the vehicle reached calf height the rear crewman told the vehicle commander they would need to evacuate.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">At this point the vehicle commander told \u00adinvestigators that he ordered the crew to \u201cdrop their stuff\u201d and open up the cargo hatches.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">All the Marines who died were found wearing their small arms protective insert carriers. Seven still had their Kevlar helmets on and two still had their rifles on their body.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Due to the failure of the emergency egress lighting system the Marines started to prepare for evacuation in near complete darkness, trying to use their \u00adcellphones as flashlights.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A broken handle on the starboard hatch slowed down the process. But eventually it was opened.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The AAV crew started to help the infantry Marines and Navy corpsman evacuate from the vehicle.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But a collision with one of the other AAVs \u00adattempting to help pushed the sinking AAV broadside in the waves.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Soon, a large wave hit the AAV, knocking the few Marines who already had escaped into the water.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cEverything starts to run together in my mind,\u201d the vehicle commander said. \u201cI remember the Marines who are still in the back of the vehicle just looking at me. I remember that I got knocked off by a wave, and I remember swimming over to one of the other tracks.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Once the wave hit the AAV, the vehicle started to rapidly fill with water. It went nose high and sank into the ocean.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI saw Track 5 sinking,\u201d a Marine on an assisting AAV told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cAt the time I didn\u2019t realize how many people were still in Track 5 because they were not trying to get out of the hatch. I assume that the people inside the \u00advehicle were either already drowned or drowning because they were not trying to get out.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><b>\u2018A small bubble of air\u2019<\/b><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Two of the AAV crewman and three of the \u00adembarked Marines made it outside of the vehicle. Eleven went down with it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The AAV driver was the only member of the crew to go down with the vehicle.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When the vehicle started to rapidly sink, he tried to escape through his hatch, but could not get it open, he told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI had a small bubble of air, so I took one breath and then climbed out of the back of the vehicle,\u201d the driver told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">As he was escaping through the passenger area the Marine said he felt the uniform of one of the grunts.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Pulling the Marine out of the cargo hatch the driver inflated the other Marine\u2019s life preserver, which sent him to the water\u2019s surface.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Feeling another Marine bump into him, the AAV driver inflated a second Marine\u2019s life preserver, also sending him to the surface.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">After roughly 45 seconds under the water the Marine said he finally inflated his own life preserver, which sent him to the water\u2019s surface.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI got to within 20 feet of the top and I felt that I wouldn\u2019t make it, and then I blacked out,\u201d he told investigators. \u201cThe next thing I remember when I woke up on the ship.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The three Marines who floated to the surface were pulled on top of the nearby vehicles where Marines started to conduct CPR on them.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">One of the Marines who made it out, Lance Cpl. Guillermo S. Perez, was pronounced dead on the scene after one hour of continuous CPR.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cWhile I\u2019m doing CPR on (one of the rescued Marines) I saw some water come out and then I saw some foam and blood come out,\u201d the vehicle \u00adcommander said. The name of the Marine referred to here was redacted.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cWe felt a light pulse, so I kept doing CPR until I started puking at which point I told (redacted name) to do CPR. We checked his pulse again but couldn\u2019t find anything.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Two Marines were hospitalized due to the accident, the Marine Corps said at the time.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Marines who were on the nearby AAVs, along with those who conducted rescue missions later in the day, said besides the three bodies all they had seen float to the surface were MRE boxes, rucks and inflated floatation devices.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The investigation found that all but one of the service members who went down with the vehicle eventually were able to escape. But the weight of their equipment, added to the depth of the AAV at that point, meant they would never reach the surface alive.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The flotation devices they were using were designed to allow a Marine carrying a full combat load to float on the surface. But the buoyancy provided by the device shrinks the deeper in the ocean a Marine gets \u2014 reducing by more than 50 percent by the time a Marine is 33 feet below the ocean\u2019s surface.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">From when the rear crewman first noticed the excess water to the vehicle going under took a total of roughly 45 minutes, according to the investigation.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><b>Fresh off the deadline lot<\/b><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The 15th MEU originally was slated to receive 13 allegedly well-maintained AAVs that were fresh off a previous deployment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But an unplanned reorganization saw the MEU receive vehicles from the 3rd Assault Amphibian Battalion\u2019s administrative deadline lot.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The seven vehicles sent to the MEU from the lot had not been operated for almost a year, outside of quarterly startups.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">And six of the vehicles required a tow to even make it to the repair shop, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The platoon\u2019s maintenance chief had informed the 3rd AA Battalion that the vehicles were inoperable and the platoon did not have the personnel to fix them in time for the deployment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But instead of replacing the vehicles with \u00adworking AAVs the platoon was sent three additional mechanics, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">As of April 20, 2020, only one of the 13 vehicles slated to be handed over from the 3rd AA Battalion to the 15th MEU was operable.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cThe way I felt about this was that our platoon had always kind of gotten fucked over,\u201d the rear crewman who had been the platoon\u2019s assistant maintenance chief prior to the training accident told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI feel like 3rd Tracks just said, \u2018Fuck you, here\u2019s a bunch of really horrible tracks and old vehicles.\u2019\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Only 11 days earlier the commander of 3rd AA Battalion\u2019s Headquarters and Service company said the platoon had a readiness of 92 percent, according to the investigation.<\/p>\n\n\n\n\n\n<p class=\"wp-block-paragraph\">After finding out so many of the vehicles meant for the MEU were inoperable BLT 1\/4 Commander Lt. Col. Michael Regner met with the then commander of 3rd AA Battalion, Lt. Col. Keith C. Brenize.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">During the meeting Brenize told Regner that the vehicles would be fixed in time for a March exercise.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cWe literally spent two to three weeks going to work at 0500 and getting off at midnight every single day working on those vehicles,\u201d the AAV\u2019s driver told investigators. \u201cI think that some of the battalion maintenance guys were coming in some days to help out, but I\u2019m not sure.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">However, the Marines working to repair the\u00ad \u00advehicles saw a series of delays.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The vehicles still belonged to the 3rd AA Battalion, preventing them from getting priority on replacement parts or financial support from the MEU they were destined for.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">They were able to repair the vehicles enough for land use by May 3, 2020, the investigation found. By May 26, 2020, the vehicles were supposedly suitable for waterborne operations.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Though the vehicles eventually were declared \u00adoperable, an inspection of the fated vehicle after the accident found numerous mechanical problems that should have deadlined it and kept it from ever deploying.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The issues were not unique to the 3rd AA Battalion, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">After the accident, an inspection of all the AAVs in the Marine Corps was conducted with updated watertight integrity requirements and bilge pump functionality.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cA majority of the AAVs failed to meet the new inspection criteria,\u201d Rudder found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The most common failures were, \u201cbilge pump \u00addiscrepancies, inoperable emergency egress lighting systems and plenum leakage,\u201d exactly what had doomed the AAV on July 30, 2020.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The infantry Marines from BLT 1\/4 lacked the \u00adtraining required to be on the water with AAVs.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Only 11 of the 13 service members embarked on the AAV had up-to-date swim qualifications, while the corpsman aboard, Hospitalman Christopher Gnem, may have never passed a swim qualification, his \u00adstepfather, Peter Vienna, told Marine Corps Times.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Only two of the Marines from BLT 1\/4 had genuinely completed the required underwater egress training, but, through a twisted shell game around ambiguous standards, the company commander was able to make it look like they were qualified on paper.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The training would have them use a submerged vehicle egress trainer, or SVET, which simulates what it is like inside a sinking AAV in a safe environment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But, between COVID-19 restrictions and mechanical issues with the trainer, the Marines never had the opportunity to take part in the training.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Instead, the Marines used a shallow water egress training, or SWET, chair. In the SWET chair a \u00adMarine straps themselves in and is surrounded by bars. The Marine is flipped into the water and works on getting out of their harness in a shallow pool.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The SWET chair is considered a valid replacement for the Modular Amphibious Egress Trainer, or MAET, commonly known as the helo dunker, which simulates escape from a helicopter crashed into water. It is considered a valid replacement for the SVET.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Bravo Company commander said that because SWET can substitute for MAET, and MAET can substitute for SVET, that he was within regulation to substitute SVET for SWET, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cWhile it is clearly not the intent of the policy to dispose of both SVET and MAET and pronounce personnel fully (underwater egress) trained through SWET training alone, the ambiguity in the policy makes that a possible interpretation,\u201d Rudder said.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">He recommended that the ambiguity be fixed.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The infantry Marines were not the only ones missing the required training when the vehicle went down.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The entire AAV platoon assigned to the 15th MEU was missing required training before the deployment. Several of the crews had been hastily thrown together and none had spent much time in the water in the months leading up to the sinking.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When the platoon was assigned to the MEU in \u00adJanuary 2020 Marines only had four months to prepare before coming under the MEU\u2019s command.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cI did not feel that my platoon was ready to become part of the 15th MEU, at least no right off the bat in January,\u201d the AAV platoon sergeant told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Despite the approaching deployment, the priority from the 3rd AA Battalion seemed to be on Native Fury, a joint exercise that took place in the United Arab Emirates in March 2020, the platoon commander said.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The focus on Native Fury prevented the platoon from scheduling much of the training needed before the \u00adplatoon deployed on the MEU, the investigation found.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cThe platoon would be conducting the same training requirements throughout the exercise as they would here in CONUS,\u201d Brenize told investigators.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ultimately only half the platoon deployed to Native Fury, as COVID-19 restrictions led to canceled flights.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Those who did deploy to Native Fury were forced to conduct two weeks of quarantine before they resumed training.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">While on the exercise the Marines never took their AAVs into the water, the investigation said.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><b>Final evaluation<\/b><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The AAV crew on the sinking AAV had only been put together on July 27 \u2014 three days before the sinking \u2014 because the normal rear crewman in the vehicle tested positive for COVID-19.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Prior to any deployment Marines are expected to go through a Marine Corps combat readiness evaluation, which ensures the Marines are fully capable of doing their jobs in combat.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The evaluation is especially important for MEUs, as they are the Marine Corps\u2019 expeditionary response force, supposedly prepared for any situation, from war to humanitarian aid, that the Corps could be called to respond to.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In September 2001, elements of the 15th MEU were in East Timor rendering humanitarian aid, while others were in Darwin, Australia. Two months later they were part of the initial invasion into Afghanistan.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The responsibility to hold the \u00adevaluation fell on the commander of the 1st Marine Division, then Maj. Gen. Robert Castellvi and commander of the 3rd AA Battalion, Brenize.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Brenize told investigators that he \u00adbelieved the platoon met all training and readiness standards and that a MCCRE was not required because it was only a platoon and not a company or larger size force.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The AAV platoon commander told investigators that he was not aware that a MCCRE was necessary before his \u00adMarines joined the MEU.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In fact, he told investigators that no one from the 3rd AA Battalion ever asked him for a training plan or even a brief on his platoon\u2019s readiness and capabilities prior to the deployment.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The platoon commander had told the Bravo BLT 1\/4 commander about his concerns and the two talked about potential extra training that could be conducted, but between COVID-19 restrictions and \u201c\u00adother reasons,\u201d the training never \u00admaterialized, the investigation found.<\/p>\n\n\n\t<aside class=\"smg-interstitial-link wp-block-smg-interstitial-link\">\n\t\t<a href=\"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/06\/marine-corps-launches-a-third-investigation-into-deadly-amphibious-assault-vehicle-accident\/\" class=\"smg-interstitial-link__inner\">\n\t\t\t\t\t\t\t<div class=\"smg-interstitial-link__media\">\n\t\t\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"300\" height=\"169\" src=\"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/marines_beach.jpg.jpg?w=300\" class=\"smg-interstitial-link__image wp-post-image\" alt=\"\" \/>\t\t\t\t<\/div>\n\t\t\t\t\t\t<div class=\"smg-interstitial-link__content\">\n\t\t\t\t<span class=\"smg-interstitial-link__kicker\">Related<\/span>\n\t\t\t\t<h3 class=\"smg-interstitial-link__title\">Marine Corps launches a third investigation into deadly amphibious assault vehicle accident<\/h3>\n\t\t\t\t\t\t\t\t\t<p class=\"smg-interstitial-link__excerpt\">This time the focus is on the 15th Marine Expeditionary Unit.<\/p>\n\t\t\t\t\t\t\t<\/div>\n\t\t<\/a>\n\t<\/aside>\n\t\n\n\n<p class=\"wp-block-paragraph\">The Marine Corps has not said whether any punishment will be \u00adhanded out to Brenize or Castellvi, both of whom have moved on from their previous commands.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Castellvi is now the inspector general of the Marine Corps, in charge of the \u00adorganization that inspects training \u00adfailures like the sinking of the AAV.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Rudder recommended that \u00adCastellvi receive no disciplinary actions \u00adbecause even though he sent Marines to a \u00addeployment without the proper training, the MEU could have made up the training lapses after it received the Marines and because, \u201che was not the on-scene commander during the mishap.\u201d<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A copy of the investigation has been sent to Training and Education \u00adCommand, where Brenize is assigned, for action.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cDisciplinary action may become a matter of public record whereas adverse administrative measures typically do not,\u201d said Capt. Andrew Wood, a spokesman for Headquarters Marine Corps.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u201cSome adverse administrative measures are included in the service member\u2019s personnel record and have lasting adverse impacts on future promotion and career advancement,\u201d he added.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The Marine Corps is in the process of taking 54 actions to ensure that this training accident will not happen again.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Of those actions, 22 are \u201cinstitutional\u201d while 32 are up to \u201cthe Fleet Marine Forces, supporting establishments and\/or Logistics Command,\u201d to complete, Wood told Marine Corps Times.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Of the institutional tasks five have been completed, 12 are in progress while the last five have been started, Wood said.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>A look inside the investigation:<\/p>\n","protected":false},"author":7,"featured_media":34025,"comment_status":"open","ping_status":"open","sticky":false,"template":"single-post-featured-layout","format":"standard","meta":{"_acf_changed":false,"_yoast_wpseo_meta-robots-noindex":"","_yoast_wpseo_meta-robots-nofollow":"","_yoast_wpseo_canonical":"","_acf":"","_yoast_wpseo_primary_category":69,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","_smg_distribution_targets":{"2":{"categories":["your-military","news","disaster","left-column","home"],"primary_category":"your-military"},"7":{"categories":["your-navy","news","daily-news-roundup","newsletters","disaster","middle-column","home"],"primary_category":"your-navy"}}},"categories":[101,22,12,25,69],"tags":[],"coauthors":[3097],"class_list":["post-18768","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-daily-news-roundup","category-disaster","category-news","category-newsletters","category-your-marine-corps"],"acf":{"subheadline":"","legacy_arc_id":"IHMLWBBEPJCCFIWJ5KTSD7NSQI","arc_canonical_url":"\/news\/your-marine-corps\/2021\/04\/15\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/","remove_feature_photo":false,"is_sponsored":false,"subtype":"featured-layout","redirect_url":"","disable_inline_ads":false,"native_logo_pretext":"Presented By:"},"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v26.0 (Yoast SEO v28.1) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>What caused the Marine amphibious assault vehicle sinking tragedy? - Marine Corps Times<\/title>\n<meta name=\"description\" content=\"A look inside the investigation:\" \/>\n<meta name=\"robots\" content=\"noindex, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"What caused the Marine amphibious assault vehicle sinking tragedy?\" \/>\n<meta property=\"og:description\" content=\"A look inside the investigation:\" \/>\n<meta property=\"og:url\" content=\"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/\" \/>\n<meta property=\"og:site_name\" content=\"Marine Corps Times\" \/>\n<meta property=\"article:published_time\" content=\"2021-04-16T02:49:39+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-08-08T20:15:18+00:00\" \/>\n<meta name=\"author\" content=\"Philip Athey\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Philip Athey\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"19 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\n\t    \"@context\": \"https:\\\/\\\/schema.org\",\n\t    \"@graph\": [\n\t        {\n\t            \"@type\": \"Article\",\n\t            \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#article\",\n\t            \"isPartOf\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/\"\n\t            },\n\t            \"author\": {\n\t                \"name\": \"migration\",\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#\\\/schema\\\/person\\\/cc76c831bb37a926738c8391fca7a3b1\"\n\t            },\n\t            \"headline\": \"What caused the Marine amphibious assault vehicle sinking tragedy?\",\n\t            \"datePublished\": \"2021-04-16T02:49:39+00:00\",\n\t            \"dateModified\": \"2026-08-08T20:15:18+00:00\",\n\t            \"mainEntityOfPage\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/\"\n\t            },\n\t            \"wordCount\": 3777,\n\t            \"commentCount\": 0,\n\t            \"publisher\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#organization\"\n\t            },\n\t            \"image\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#primaryimage\"\n\t            },\n\t            \"thumbnailUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/aav-facebook-v2.jpg.jpg\",\n\t            \"articleSection\": [\n\t                \"Daily News Roundup\",\n\t                \"Disaster | Advertiser Safety\",\n\t                \"News\",\n\t                \"Newsletters\",\n\t                \"Your Marine Corps\"\n\t            ],\n\t            \"inLanguage\": \"en-US\",\n\t            \"potentialAction\": [\n\t                {\n\t                    \"@type\": \"CommentAction\",\n\t                    \"name\": \"Comment\",\n\t                    \"target\": [\n\t                        \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#respond\"\n\t                    ]\n\t                }\n\t            ]\n\t        },\n\t        {\n\t            \"@type\": \"WebPage\",\n\t            \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/\",\n\t            \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/\",\n\t            \"name\": \"What caused the Marine amphibious assault vehicle sinking tragedy? - Marine Corps Times\",\n\t            \"isPartOf\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#website\"\n\t            },\n\t            \"primaryImageOfPage\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#primaryimage\"\n\t            },\n\t            \"image\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#primaryimage\"\n\t            },\n\t            \"thumbnailUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/aav-facebook-v2.jpg.jpg\",\n\t            \"datePublished\": \"2021-04-16T02:49:39+00:00\",\n\t            \"dateModified\": \"2026-08-08T20:15:18+00:00\",\n\t            \"description\": \"A look inside the investigation:\",\n\t            \"breadcrumb\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#breadcrumb\"\n\t            },\n\t            \"inLanguage\": \"en-US\",\n\t            \"potentialAction\": [\n\t                {\n\t                    \"@type\": \"ReadAction\",\n\t                    \"target\": [\n\t                        \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/\"\n\t                    ]\n\t                }\n\t            ]\n\t        },\n\t        {\n\t            \"@type\": \"ImageObject\",\n\t            \"inLanguage\": \"en-US\",\n\t            \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#primaryimage\",\n\t            \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/aav-facebook-v2.jpg.jpg\",\n\t            \"contentUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/08\\\/aav-facebook-v2.jpg.jpg\"\n\t        },\n\t        {\n\t            \"@type\": \"BreadcrumbList\",\n\t            \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/2021\\\/04\\\/16\\\/what-caused-the-marine-amphibious-assault-sinking-tragedy\\\/#breadcrumb\",\n\t            \"itemListElement\": [\n\t                {\n\t                    \"@type\": \"ListItem\",\n\t                    \"position\": 1,\n\t                    \"name\": \"Home\",\n\t                    \"item\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/\",\n\t                    \"ad_zone\": \"home\"\n\t                },\n\t                {\n\t                    \"@type\": \"ListItem\",\n\t                    \"position\": 2,\n\t                    \"name\": \"News\",\n\t                    \"item\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/\",\n\t                    \"ad_zone\": \"news\"\n\t                },\n\t                {\n\t                    \"@type\": \"ListItem\",\n\t                    \"position\": 3,\n\t                    \"name\": \"Your Marine Corps\",\n\t                    \"item\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/news\\\/your-marine-corps\\\/\",\n\t                    \"ad_zone\": \"your-marine-corps\"\n\t                },\n\t                {\n\t                    \"@type\": \"ListItem\",\n\t                    \"position\": 4,\n\t                    \"name\": \"What caused the Marine amphibious assault vehicle sinking tragedy?\"\n\t                }\n\t            ]\n\t        },\n\t        {\n\t            \"@type\": \"WebSite\",\n\t            \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#website\",\n\t            \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/\",\n\t            \"name\": \"Marine Corps Times\",\n\t            \"description\": \"Marine Corps - Independent News For Marines | Marine Corps Times\",\n\t            \"publisher\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#organization\"\n\t            },\n\t            \"potentialAction\": [\n\t                {\n\t                    \"@type\": \"SearchAction\",\n\t                    \"target\": {\n\t                        \"@type\": \"EntryPoint\",\n\t                        \"urlTemplate\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/?s={search_term_string}\"\n\t                    },\n\t                    \"query-input\": {\n\t                        \"@type\": \"PropertyValueSpecification\",\n\t                        \"valueRequired\": true,\n\t                        \"valueName\": \"search_term_string\"\n\t                    }\n\t                }\n\t            ],\n\t            \"inLanguage\": \"en-US\"\n\t        },\n\t        {\n\t            \"@type\": \"Organization\",\n\t            \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#organization\",\n\t            \"name\": \"Marine Corps Times\",\n\t            \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/\",\n\t            \"logo\": {\n\t                \"@type\": \"ImageObject\",\n\t                \"inLanguage\": \"en-US\",\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#\\\/schema\\\/logo\\\/image\\\/\",\n\t                \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/marine-logo-white.png\",\n\t                \"contentUrl\": \"https:\\\/\\\/one.sightlinemg.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/marine-logo-white.png\",\n\t                \"caption\": \"Marine Corps Times\"\n\t            },\n\t            \"image\": {\n\t                \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#\\\/schema\\\/logo\\\/image\\\/\"\n\t            }\n\t        },\n\t        {\n\t            \"@type\": \"Person\",\n\t            \"@id\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/#\\\/schema\\\/person\\\/cc76c831bb37a926738c8391fca7a3b1\",\n\t            \"name\": \"migration\",\n\t            \"image\": {\n\t                \"@type\": \"ImageObject\",\n\t                \"inLanguage\": \"en-US\",\n\t                \"@id\": \"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=gcf4cb6ee0ec29e49e7a963234e4340ec\",\n\t                \"url\": \"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g\",\n\t                \"contentUrl\": \"https:\\\/\\\/secure.gravatar.com\\\/avatar\\\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g\",\n\t                \"caption\": \"migration\"\n\t            },\n\t            \"url\": \"https:\\\/\\\/one.sightlinemg.com\\\/marinecorpstimes\\\/author\\\/migration\\\/\"\n\t        }\n\t    ]\n\t}<\/script>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"What caused the Marine amphibious assault vehicle sinking tragedy? - Marine Corps Times","description":"A look inside the investigation:","robots":{"index":"noindex","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"og_locale":"en_US","og_type":"article","og_title":"What caused the Marine amphibious assault vehicle sinking tragedy?","og_description":"A look inside the investigation:","og_url":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/","og_site_name":"Marine Corps Times","article_published_time":"2021-04-16T02:49:39+00:00","article_modified_time":"2026-08-08T20:15:18+00:00","author":"Philip Athey","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Philip Athey","Est. reading time":"19 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"Article","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#article","isPartOf":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/"},"author":{"name":"migration","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#\/schema\/person\/cc76c831bb37a926738c8391fca7a3b1"},"headline":"What caused the Marine amphibious assault vehicle sinking tragedy?","datePublished":"2021-04-16T02:49:39+00:00","dateModified":"2026-08-08T20:15:18+00:00","mainEntityOfPage":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/"},"wordCount":3777,"commentCount":0,"publisher":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#organization"},"image":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#primaryimage"},"thumbnailUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/aav-facebook-v2.jpg.jpg","articleSection":["Daily News Roundup","Disaster | Advertiser Safety","News","Newsletters","Your Marine Corps"],"inLanguage":"en-US","potentialAction":[{"@type":"CommentAction","name":"Comment","target":["https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#respond"]}]},{"@type":"WebPage","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/","url":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/","name":"What caused the Marine amphibious assault vehicle sinking tragedy? - Marine Corps Times","isPartOf":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#website"},"primaryImageOfPage":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#primaryimage"},"image":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#primaryimage"},"thumbnailUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/aav-facebook-v2.jpg.jpg","datePublished":"2021-04-16T02:49:39+00:00","dateModified":"2026-08-08T20:15:18+00:00","description":"A look inside the investigation:","breadcrumb":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/"]}]},{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#primaryimage","url":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/aav-facebook-v2.jpg.jpg","contentUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/aav-facebook-v2.jpg.jpg"},{"@type":"BreadcrumbList","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/2021\/04\/16\/what-caused-the-marine-amphibious-assault-sinking-tragedy\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/","ad_zone":"home"},{"@type":"ListItem","position":2,"name":"News","item":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/","ad_zone":"news"},{"@type":"ListItem","position":3,"name":"Your Marine Corps","item":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/news\/your-marine-corps\/","ad_zone":"your-marine-corps"},{"@type":"ListItem","position":4,"name":"What caused the Marine amphibious assault vehicle sinking tragedy?"}]},{"@type":"WebSite","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#website","url":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/","name":"Marine Corps Times","description":"Marine Corps - Independent News For Marines | Marine Corps Times","publisher":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#organization","name":"Marine Corps Times","url":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#\/schema\/logo\/image\/","url":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/06\/marine-logo-white.png","contentUrl":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/06\/marine-logo-white.png","caption":"Marine Corps Times"},"image":{"@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#\/schema\/logo\/image\/"}},{"@type":"Person","@id":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/#\/schema\/person\/cc76c831bb37a926738c8391fca7a3b1","name":"migration","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/secure.gravatar.com\/avatar\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=gcf4cb6ee0ec29e49e7a963234e4340ec","url":"https:\/\/secure.gravatar.com\/avatar\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/9e8d47be443ce94ce7fc357677b5f9c70235bb1f59e7267a102a74af58c04f59?s=96&d=mm&r=g","caption":"migration"},"url":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/author\/migration\/"}]}},"jetpack_sharing_enabled":true,"distributor_meta":false,"distributor_terms":false,"distributor_media":false,"distributor_original_site_name":"Marine Corps Times","distributor_original_site_url":"https:\/\/one.sightlinemg.com\/marinecorpstimes","push-errors":false,"jetpack_featured_media_url":"https:\/\/one.sightlinemg.com\/wp-content\/uploads\/2026\/08\/aav-facebook-v2.jpg.jpg","_links":{"self":[{"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/posts\/18768","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/comments?post=18768"}],"version-history":[{"count":2,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/posts\/18768\/revisions"}],"predecessor-version":[{"id":94513,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/posts\/18768\/revisions\/94513"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/posts\/34025"}],"wp:attachment":[{"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/media?parent=18768"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/categories?post=18768"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/tags?post=18768"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/one.sightlinemg.com\/marinecorpstimes\/wp-json\/wp\/v2\/coauthors?post=18768"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}