RV Petrel#Akagi

Prior to 2020, the primary mission of the ship, which was fully funded by Allen's estate, was to explore historically significant wrecks at challenging depths and conditions. A precondition set by Allen was for discovered wrecks to be respected as war graves and their locations kept secret, known to only national governments and museums. In the PBS documentary USS Indianapolis Live from the Deep, Allen said, "We've done a number of these explorations to try to find sunken warships. We try to do these both as really exciting examples of underwater archaeology and as tributes to the brave men [who] went down on these ships".{{Cite web|url=https://www.pbs.org/show/uss-indianapolis/|title=USS Indianapolis LIVE - From the Deep|website=USS Indianapolis LIVE - From the Deep {{!}} PBS|access-date=24 July 2018}} Petrel{{'}}s other mission profile included hosting scientific projects under Allen's mother company, Vulcan Inc.

Petrel explorations were coordinated with organizations around the world. For United States Navy wrecks, the team collaborated with the Naval History and Heritage Command. In the Philippines, the crew worked with the National Museum and the Battle of Surigao Strait Memorial Council.{{Cite news|url=http://news.abs-cbn.com/focus/12/01/17/explorers-who-found-wreck-of-worlds-biggest-battleship-get-national-museum-nod|title=Explorers who found wreck of world's biggest battleship get National Museum nod|work=ABS-CBN News|date=2017-12-01|access-date=24 July 2018}} In 2018, Petrel worked with Australian National Maritime Museum to explore {{HMAS|AE1}}. Robert Kraft, who served as subsea director for Allen, and Paul Mayer, Petrel{{'}}s lead researcher, traveled to Japan to hand over ROV video of Imperial Japanese Navy wrecks to the Yamato Museum.{{citation needed|date=March 2023}}

The project crew was aboard Allen's {{ship||Octopus|yacht|2}} operating the megayacht's crewed-submersible Pagoo, Argus 3000 remotely operated vehicle (ROV) and Bluefin 12D autonomous underwater vehicle (AUV). The 20 civilian marine crew and 10 project crew worked on 12-hour shifts aboard Petrel. The project crew consisted of Kraft the expedition leader, Mayer as lead researcher, four ROV pilots and technicians, one AUV specialist, one multibeam surveyor, one videographer, and one systems support engineer. For each expedition, local historians, scientists, and observers complemented the project crew.

The team, while on board Octopus, mapped {{Convert|380|sqmi|abbr=on}} of Ironbottom Sound in January 2015, identified 29 wreck locations, seven wreck debris fields, and several possible plane locations. Of the 29 wrecks located, six were positively identified and confirmed to be the heavy cruisers {{USS|Astoria|CA-34|6}}, {{USS|Quincy|CA-39|2}}, {{USS|Vincennes|CA-44|2}}, {{USS|Northampton|CA-26|2}}, and {{HMAS|Canberra|D33|6}}, and the light cruiser {{USS|Atlanta|CL-51|2}}. Eleven wrecks were "tentatively" identified to be the Japanese destroyers {{ship|Japanese destroyer|Ayanami|1929|2}}, {{ship|Japanese destroyer|Yūdachi|1936|2}} and {{ship|Japanese destroyer|Fubuki|1927|2}}, and the American destroyers {{USS|Walke|DD-416|6}}, {{USS|De Haven|DD-469|6}}, {{USS|Laffey|DD-459|6}}, {{USS|Monssen|DD-436|6}}, {{USS|Barton|DD-599|6}}, {{USS|Cushing|DD-376|6}}, {{USS|Little|DD-79|6}}, and {{USS|Preston|DD-379|6}}. The identification using the sonar imagery with vessel measurements and historical records is pending confirmation by ROV exploration. The remaining 12 wreck locations were not identified during the expedition and require further study.{{Cite web|url= https://www.oceannews.com/featured-stories/may-feature-story |title=Mapping the Ghost Fleet of Iron Bottom Sound |website=ONT |access-date=2023-03-22 |date=2015-06-01}}

After several years of searching, the same team discovered the {{ship|Japanese battleship|Musashi}} in March 2015.{{Cite web|url=http://www.superyachtnews.com/owner/finding_the_musashi|title=M/Y Octopus finds the Musashi – SuperyachtNews|last=Group|first=The Superyacht|website=Superyacht News|language=en|archiveurl=https://web.archive.org/web/20171210232700/http://www.superyachtnews.com/owner/finding_the_musashi|archivedate=10 December 2017|url-status=live|access-date=10 December 2017|date=9 March 2015}}

In August 2015, the team recovered the bell of {{HMS|Hood}} after obtaining license from the UK Ministry of Defence. The recovery of the bell was performed upon the request of the HMS Hood Association. Only three of HMS Hood{{'}}s crew survived and it was the wish of one of them to recover ship's bell as a memorial to shipmates. The bell from HMS Hood was unveiled by the Princess Royal on 24 May 2016 to mark the 75th anniversary of the Royal Navy's largest loss of life (1,415 sailors) from a single vessel.{{Cite web|url=https://www.telegraph.co.uk/application/errorpages/500/|title=500|website=The Telegraph|archiveurl=https://web.archive.org/web/20171210135352/http://www.telegraph.co.uk/application/errorpages/500/|archivedate=10 December 2017|url-status=dead|access-date=10 December 2017}}

File:Bluefin 12 AUV mapping of seabed around Malta.jpg

While on board Octopus, the project crew deployed a Bluefin 12D AUV and mapped {{convert|630|km2|0|abbr=on}} of seabed around Malta in September 2015. Sonar images of shipwrecks, several aircraft, torpedoes, and debris field were captured by the AUV.

Following the Musashi discovery and the Hood expedition in 2015, Allen bought Petrel in 2016, refitting her as a dedicated research and exploration platform.

Petrel found the Italian Regia Marina World War II destroyer {{ship|Italian destroyer|Artigliere|1937|2}} in March 2017.{{Cite news|url=https://www.foxnews.com/tech/sunken-world-war-ii-italian-warship-artigliere-located-and-explored-for-first-time|title=Sunken World War II Italian warship Artigliere located and explored for first time|date=6 June 2017|work=Fox News|access-date=9 December 2017|language=en-US|url-status=live|archive-url=https://web.archive.org/web/20170820040952/http://www.foxnews.com/tech/2017/06/06/sunken-world-war-ii-italian-warship-artigliere-located-and-explored-for-first-time.html|archive-date=20 August 2017}}

Petrel found {{USS|Indianapolis|CA-35|6}} in August 2017.{{Cite news|url=https://edition.cnn.com/2017/08/19/us/uss-indianapolis-wreckage-found/index.html|title=USS Indianapolis wreckage found 72 years later|first=Emanuella |last=Grinberg|work=CNN|access-date=9 December 2017|url-status=live|archive-url=https://web.archive.org/web/20171204001653/http://edition.cnn.com/2017/08/19/us/uss-indianapolis-wreckage-found/index.html|archive-date=4 December 2017}} Indianapolis was located on 19 August 2017 at a depth of {{convert|5500|m|abbr=on}} in the Philippine Sea. The discovery introduced Petrel as Paul Allen's newest addition to his expedition fleet. Kraft said of the elusive Indianapolis, "We did 18 search grids, each one is about a 120 square kilometers and that took us the course of a couple of months. It was about 26 days of searching".

The Indianapolis wreck is upright with her hull and armaments intact and well preserved in the depth. Her bow number 35 was seen by the ROV. Rusticles or oxidized wrought iron were found by the crew emerging from one of the main guns of the ship.{{Cite news|url=https://news.usni.org/2017/09/14/28213|title=PBS Broadcast Shows USS Indianapolis is a 'Well Preserved' Hull |date=14 September 2017|work=USNI News|access-date=14 December 2017|language=en-US|url-status=live|archiveurl=https://web.archive.org/web/20170914215204/https://news.usni.org/2017/09/14/28213|archivedate=14 September 2017}}

After discovering USS Indianapolis, Petrel sailed to Surigao City in October 2017 to participate in the 73rd commemoration of the Battle of Surigao Strait.{{Cite web|url=http://www.surigaoislands.com/forum/news-announcements/1284-joint-exploration-of-the-surigao-strait-wrecks-wit.html|title=Philippines :: Topic: joint exploration of the Surigao Strait wrecks wit (1/1)|website=www.surigaoislands.com|language=en-gb|access-date=9 December 2017|url-status=live|archiveurl=https://web.archive.org/web/20171215140812/http://www.surigaoislands.com/forum/news-announcements/1284-joint-exploration-of-the-surigao-strait-wrecks-wit.html|archivedate=15 December 2017}} In November 2017, after gaining approval from the Philippines' National Museum, Petrel surveyed Surigao Strait and discovered the wrecks of the Japanese battleships {{ship|Japanese battleship|Yamashiro||2}}, {{ship|Japanese battleship|Fusō||2}}, and the destroyers {{ship|Japanese destroyer|Michishio||2}}, {{ship|Japanese destroyer|Yamagumo|1937|2}}, and {{ship|Japanese destroyer|Asagumo|1937|2}}. Each one was investigated by the ship's ROV and an onboard local historian confirmed the identity of the wreck.{{Cite news|url=https://philippinesgraphic.net/remembering-the-forgotten-fleet/|title=Remembering the Forgotten Fleet|date=4 December 2017|work=The Philippines Graphic|access-date=9 December 2017|language=en-US|url-status=live|archiveurl=https://web.archive.org/web/20171210180324/https://philippinesgraphic.net/remembering-the-forgotten-fleet/|archivedate=10 December 2017}}

In December 2017, Petrel explored Ormoc Bay and discovered the wrecks of the American destroyers {{USS|Ward|DD-139|6}}, {{USS|Cooper}}, the {{ship|Japanese destroyer|Shimakaze|1942|6}}, and what is believed to be two {{sclass|Yūgumo|destroyer|2}}s. The discovery of the wreck of USS Ward was a central theme for the 76th commemoration of the Attack on Pearl Harbor on 7 December.{{Cite web|url=https://www.paulallen.com/rv-petrel/rv-petrel-explores-wreck-of-uss-ward|title=R/V Petrel Explores Wreck of USS Ward; Fired First American Shot of WWII | PaulAllen.com|website=PAUL ALLEN|accessdate=21 October 2019}}

In early January 2018, Petrel returned to Ormoc Bay and dived one of the Yūgumo-class destroyers found in 2017. Based on the {{convert|127|mm|0|abbr=on}} guns and armament configuration, she was identified to be {{ship|Japanese destroyer|Hamanami||2}}. The identification also validated the final resting places of the other ships of the lost Japanese convoy TA-4: the destroyers {{ship|Japanese destroyer|Shimakaze|1942|2}}, {{ship|Japanese destroyer|Wakatsuki||2}} and {{ship|Japanese destroyer|Naganami||2}}. The convoy was attacked by aircraft from Task Force 38 in the Battle of Ormoc Bay. Petrel and Octopus also dove their crewed submersible Pagoo on USS Cooper.

In February 2018, Petrel, with a US Navy team aboard, located and mapped the wreckage of a Grumman C-2 Greyhound aircraft that crashed into the Philippine Sea en route to {{USS|Ronald Reagan}} on 22 November 2017.{{Cite web|url=https://globaldefensenews.com/u-s-navy-mapped-wreckage-c-2a-greyhound-crashed-ocean|title=U.S. Navy mapped the wreckage of C-2A Greyhound that crashed into the Ocean|website=globaldefensenews.com|language=en-US|access-date=5 March 2018|url-status=usurped|archive-url=https://web.archive.org/web/20180307032733/https://globaldefensenews.com/u-s-navy-mapped-wreckage-c-2a-greyhound-crashed-ocean|archive-date=7 March 2018}}

On 4 March 2018, Petrel explored the Coral Sea and discovered the wreck of the aircraft carrier {{USS|Lexington|CV-2|6}}, which sank during the Battle of the Coral Sea.{{Cite web|url=https://news.usni.org/2018/03/05/video-billionaire-paul-allen-finds-lost-world-war-ii-carrier-uss-lexington|title=VIDEO: Billionaire Paul Allen Finds Lost World War II Carrier USS Lexington|date=5 March 2018}}

On 17 March 2018, Petrel located the wreck of the antiaircraft light cruiser {{USS|Juneau|CL-52|6}}. Juneau was sunk by the {{Ship|Japanese submarine|I-26}} in the aftermath of the first Naval Battle of Guadalcanal, sinking with the loss of 687 men, which included the five Sullivan brothers.{{cite web |url=https://www.paulallen.com/uss-juneau-wreck-located-famous-for-sullivan-brothers/ |title=Sunken USS Juneau Famous for the Sullivan Brothers Discovered on St. Patrick's Day |date=19 March 2018 |work=paulallen.com |publisher=Vulcan Inc. |access-date=19 March 2018 |archive-date=20 March 2018 |archive-url=https://web.archive.org/web/20180320230926/https://www.paulallen.com/uss-juneau-wreck-located-famous-for-sullivan-brothers/ |url-status=dead }}{{cite news |url=https://news.usni.org/2018/03/19/paul-allen-finds-sullivan-brothers-cruiser-uss-juneau |title=Paul Allen Finds Sullivan Brothers' Cruiser USS Juneau |last=LaGrone |first=Sam |date=19 March 2018 |work=USNI News |publisher=U.S. Naval Institute |access-date=19 March 2018}}

On 11 April 2018, Petrel located the wreck of the light cruiser {{USS|Helena|CL-50|6}}. Helena was sunk during the Battle of Kula Gulf in 1943 by three torpedoes fired from a Japanese destroyer with a loss of 168 of her crew.{{cite web |url=https://www.paulallen.com/uss-helena/ |title=USS Helena Discovered: A Story of Valor and Perseverance |website=paulallen.com |date=11 April 2018 |accessdate=11 April 2018}}

The Royal Australian Navy's submarine {{HMAS|AE1}}, which was lost at sea with all hands on 14 September 1914, and only discovered in December 2017 on the seafloor off the Duke of York Islands in Papua New Guinea (PNG), was visited by Petrel{{'}}s ROV. Petrel{{'}}s crew devised a close-up camera to view details inside the torpedo tube and engine telegraph. This exploration published on 23 April 2018, was supervised by Find AE1 Ltd in partnership with the Australian National Maritime Museum, the Royal Australian Navy, Curtin University, the Western Australian Museum, and the Submarine Institute of Australia. The approval for the survey was granted by Papua New Guinea National Museum and Art Gallery.

Petrel found the wreck of the {{ship|Japanese destroyer|Niizuki}} upright in {{convert|745|m|ft|abbr=on}} of water in January 2019. While the wreck was heavily damaged, her mast is still attached and complete. The find of Niizuki was noteworthy because she was credited for sinking {{USS|Strong|DD-467|6}} with the longest torpedo shot ever, with estimates ranging from {{convert|7|to|11|nmi}}.{{Cite web|url=https://www.facebook.com/rvpetrel/videos/586982841782188/|title=IJN Niizuki|website=RV Petrel-Facebook|language=en|date=2019-04-17|access-date=2019-04-27}} Niizuki{{'}}s discovery is also noteworthy as the photos of the wreck are the first photos of the ship to exist; no photos of her in service are known to have been taken.

In February 2019, the {{ship|Japanese cruiser|Jintsū}}'s wreckage was discovered by Petrel near the mouth of Kula Gulf in the Solomon Islands. The broken cruiser rests in {{convert|900|m|ft|abbr=on}} of water. Her bow section is lying on its port side and the stern section is upright.{{Cite web|url=https://www.facebook.com/rvpetrel/videos/321737998511513/|title=IJN Jintsu|website=RV Petrel-Facebook|language=en|date=2019-04-26|access-date=2019-04-27}}

On 6 February 2019, the discovery of the {{ship|Japanese battleship|Hiei}} was announced, the first Japanese battleship sunk in World War II. According to Petrel, Hiei now lies upside down in {{convert|900|m|abbr=on}} of water northwest of Savo Island in the Solomon Islands. Hiei is the fourth Japanese battleship found by Petrel{{'}}s crew. The {{ship|Japanese battleship|Musashi}} was found in March 2015, and the {{sclass|Fusō|battleship|2}}s {{ship|Japanese battleship|Fusō||2}} and {{ship|Japanese battleship|Yamashiro||2}} were found in November 2017. Petrel was also able to survey another {{sclass|Kongō|battlecruiser|1}}, {{ship|Japanese battleship|Kirishima||2}}, in a separate mission. Lead researcher Paul Mayer said that Hiei lies {{convert|4|nmi|lk=in}} away from Kirishima.{{Cite web|url=https://www.facebook.com/rvpetrel/videos/318434312141233|title=Hiei-Kirishima|website=RV Petrel-Facebook|language=en|date=2019-02-02|access-date=2019-04-27}}

On 12 February 2019, the crew announced they had located the wreck of the aircraft carrier {{USS|Hornet|CV-8|6}} at a depth of more than {{convert|17700|ft|abbr=on}} off the Solomon Islands.{{cite news|title=Wreckage of World War II aircraft carrier USS Hornet discovered|url=https://www.cbsnews.com/news/uss-hornet-wreckage-world-war-two-warship-discovered/|website=cbsnews.com|date=12 February 2019|accessdate=12 February 2019}} She is in remarkably good condition. She sits right-side up with her island still in place. A portion of her flight deck has collapsed due to the fire that raged on her decks during the battle. A portion of her stern is torn away, but the hull remains mostly intact. Several aircraft are scattered among the wreck.

On 26 February 2019, the crew announced they had located the wreck of the destroyer {{USS|Strong|DD-467|6}}, resting at a depth of {{convert|1,000|ft|m|abbr=on}}.{{Cite web|url=https://www.geekwire.com/2019/lost-1943-uss-strong-found-paul-allens-petrel-research-vessel/|title=Lost in 1943, the USS Strong is found again by Paul Allen's Petrel research vessel|date=25 February 2019|website=GeekWire}} She rests in pieces, the largest of which is the heavily damaged forward section of the ship lying on its port side. The rest of the ship was largely fragmented by the detonation of her depth charges and lies in a compact debris field that includes the ship's boilers, propellers, and wheelhouse.{{cite web |url=https://www.facebook.com/rvpetrel/videos/368327814005027/?f=AbqfsxM3nkY5jdqQSVeO-NpY9RmwAsyIN1hfCmvkFX-_L_VXzskB8iwWqT435W2SsExQn2CtUGKZDikvRI9MIyn_uCp79vSbaKdG5o7F0HI5tg1ePHNk5kh8EylXJ1WTq5I&filters=eyJycF9hdXRob3IiOiJ7XCJuYW1lXCI6XCJteV9ncm91cHNfYW5kX3BhZ2VzX3Bvc3RzXCIsXCJhcmdzXCI6XCJcIn0ifQ%3D%3D&epa=SEE_MORE |title=USS Strong DD-467 |website=facebook.com |date=27 February 2019 |access-date=20 February 2022}}{{reliable source|date=February 2022}}

On 13 March 2019, the crew announced they had located the wreck of the aircraft carrier, {{USS|Wasp|CV-7|6}} resting at a depth of {{convert|13,800|ft|m}}.{{Cite web|url=http://warbirdsnews.com/aircraft-restoration/paul-g-allen-expedition-discovers-the-sunken-uss-wasp-and-her-aircraft.html|title=Paul G. Allen Expedition Discovers the Sunken USS Wasp and Her Aircraft|date=13 March 2019}} The ship sits upright, though appears to have broken in two places, just forward and just aft of the island, apparently on impact with the seabed. The island itself is still in place, though the funnel structure was ripped off during the sinking. Several aircraft were also found in the debris field, including Dauntlesses and Avengers.{{Cite web|url=https://www.facebook.com/rvpetrel/videos/uss-wasp-cv-7/268156990763206/|title=USS Wasp CV-7 | A video of the USS Wasp CV-7 with (Ret.) Adm. Sam Cox, the Director of the Naval History and Heritage command talking about the Wasp. | By RV Petrel | Facebook|website=www.facebook.com}}

On 4 May 2019, the crew announced they had located the wreck of the Japanese heavy cruiser {{ship|Japanese cruiser|Furutaka||2}} at a depth of {{convert|4600|ft|m|abbr=on}}. She lies in two sections, with the bow sitting near the main part of the wreck, which is upright and the bridge is about {{convert|2000|ft|m|abbr=on}} away.{{Cite web|url=https://www.facebook.com/rvpetrel/posts/2340052046030263|title=RV Petrel|website=www.facebook.com|accessdate=21 October 2019}}{{Cite web|url=http://www.combinedfleet.com/furuta_t.htm|title=Imperial Cruisers|website=www.combinedfleet.com|accessdate=21 October 2019}}

On 1 July 2019, it was announced that the wreck of the {{ship|Japanese cruiser|Maya}} had been found off the coast of the Philippine island of Palawan. She is mostly intact, with the exception of her forward bow, which broke off and is lying upside down just astern of the rest of the ship. Her bridge and guns are also intact. She lies in {{convert|1850|m|ft|abbr=on}} of water.{{Cite web|url=https://www.facebook.com/pages/category/Science--Technology---Engineering/rvpetrel/photos/|title=RV Petrel|website=www.facebook.com|accessdate=21 October 2019}}

On 9 September 2019, it was announced that the wreck of the {{ship|Japanese cruiser|Mogami|1934|6}} had been found in the Bohol Sea. She lies mostly intact, with the exception of her forward bow, which has been blown off, but lying nearby. She sits straight side up at a depth of {{convert|1450|m|ft|abbr=on}}.{{Cite web|url=https://www.facebook.com/rvpetrel/|title=RV Petrel|website=www.facebook.com|accessdate=21 October 2019}}

On 10 October 2019, it was announced that the wreck of the escort carrier, {{USS|St. Lo}}, the first ship to have been sunk by a kamikaze, had been discovered on 25 May. She lies at a depth of {{convert|15,538|ft|m}} on the edge of the Philippine Trench off the coast of Samar. She sits upright relatively intact, with notable battle damage. She is the first escort carrier to have been found.

On 18 October 2019, Petrel announced they had discovered the wreck of the {{ship|Japanese aircraft carrier|Kaga}}, off the coast of Midway Atoll. She lies right side up, but with heavy battle damage, {{convert|5400|m}} below the surface. She is the first Japanese aircraft carrier to have been found.{{Cite web|url=https://www.maritime-executive.com/article/sunken-japanese-fleet-carrier-kaga-discovered|title=Sunken Japanese Aircraft Carrier Kaga Discovered|website=The Maritime Executive|accessdate=21 October 2019}}

On 20 October 2019, the director of undersea operations Rob Kraft and Naval History and Heritage Command historian Frank Thompson aboard Petrel identified the wreck of the {{ship|Japanese aircraft carrier|Akagi}} using high-frequency sonar. Located {{convert|1300|mi}} north west of Pearl Harbor, Hawaii, Akagi was found at a depth of {{convert|18011|ft|m}}. It is reported that the wreck is upright, on her keel, and is largely intact.{{Cite web|url=https://www.theguardian.com/world/2019/oct/21/humbling-wreckage-of-japanese-ships-from-battle-of-midway-found-in-pacific|title='Humbling' wreckage of Japanese ships from battle of Midway found in Pacific|first=Peter|last=Beaumont|date=21 October 2019|access-date=21 October 2019|work=The Guardian }} Due to damage sustained by the ROV during recovery from the preceding survey of Kaga, and a number of other factors, Petrel was unable to conduct a photographic survey of Akagi.{{cite web | url-access=limited |archive-url = https://ghostarchive.org/iarchive/facebook/1510752248960251/2669615386407259 |archive-date = 2022-04-30| url = https://www.facebook.com/rvpetrel/posts/2669615386407259?__xts__[0]=68.ARCVkS5bgVyTHTmKFZYZk_S3aSc9lz7wHo71hwgAgbY5cbxVIbhfDGULNggWlWrcOnBujTMB6H35FGzqQMa5cg97ji1rQ1bEvV6fiA8mA13-rgb7tqiZ5cRSISIgsWdHcGInZjbtJqG1PeXwFYcznr69ISCO6oAQLxWPWxce0nsWnsBp29Gj-Ozf6HP0ZU7ZmtLSQv2UPHbeQEs9LTabqCovB8CHQAuovacsgdyPXphycUkUIpGlVd8CXcL7g2IXdhi-aYeQyb-TV_egUs5v8YouMi5SOfOSD7QPj1dV9DbpdZ8lIfe0xVCBPje_VpYIhn9GGYvGrUGVtsck688wvI8A&__tn__=-R |title = RV Petrel on Facebook |website=Facebook}}{{cbignore}}{{reliable source|date=April 2021}}{{User-generated source|certain=yes|date=March 2022}}

On 26 October 2019, the search team announced they had discovered, on 5 May earlier in the year, the wreck of the {{ship|Japanese cruiser|Chōkai}} on the edge of the Philippine Deep. She lies upright with her bow section torn off, {{convert|5173|m}} deep.{{Cite web|url=https://www.facebook.com/rvpetrel/videos/706071753222186/|title=Announcement of discovery|website=Facebook|accessdate=27 October 2019}}

On 30 October 2019, it was announced that the wreckage of a destroyer believed to be {{USS|Johnston|DD-557|6}} had been located. She was believed to have been the deepest ever located shipwreck, estimated at {{convert|20,406|ft|m}} deep.{{cite news |url=https://www.foxnews.com/science/wwii-shipwreck-discovered-philippine-sea-is-the-deepest-ever-found |title=US WWII shipwreck discovered in the Philippine Sea is the deepest ever found |first=James |last=Rogers |date=30 October 2019 |work=Fox News |access-date=30 October 2019}} Her identity was confirmed on 31 March 2021, when the submersible DSV Limiting Factor of Caladan Oceanic surveyed and photographed the deeper main wreck. The visible hull number, 557, confirmed the identity of the ship as Johnston. She sits upright and well-preserved at a depth of {{cvt|21,180|ft|m}}.{{cite web |url=https://www.bbc.com/news/science-environment-56608713 |author-link=Rebecca Morelle |title=USS Johnston: Sub dives to deepest-known shipwreck |work=BBC News |last=Morelle |first=Rebecca |date=2 April 2021 |access-date=17 April 2021 }}{{cite web |url=https://www.popularmechanics.com/military/navy-ships/a36028231/uss-johnston-wreck-explorers-find-remains-sunken-wwii-destroyer/ |title=Explorers Just Found the Remains of a WWII Hero Destroyer |last=Mizokami |first=Kyle |work=Popular Mechanics |date=6 April 2021 |access-date=17 April 2021 }} The record was broken when the wreck of USS Samuel B. Roberts (DE-413) was found the following year, lying at a depth of {{cvt|22,621|ft|m}}.{{cite news |last1=Amos |first1=Jonathan |title=USS Samuel B Roberts: World's deepest shipwreck discovered |url=https://www.bbc.co.uk/news/science-environment-61925862 |access-date=10 June 2023 |work=BBC News |date=24 June 2022}}

On 19 December 2019, it was announced that Petrel had located and surveyed the wrecks of the Philippine ferry, {{MV|Doña Paz}} and the oil tanker {{ship|MT|Vector}}. Both wrecks were found {{convert|2200|m|ft}} apart at a depth of {{convert|500|m}} in the Sibuyan Sea.{{cite web |url=https://www.geekwire.com/2019/paul-allens-research-vessel-surveys-wreckage-asias-titanic-1987-ferry-sinking-killed-4300/ |title=Paul Allen's research vessel surveys wreckage of 'Asia's Titanic' — 1987 ferry sinking killed 4,300 |work=geekwire.com |date=19 December 2019 |accessdate=21 December 2019}} Both wrecks sit right side up and are in good condition.

On 24 December 2019, news came out that Petrel and a team from University of Hawaii School of Ocean and Earth Sciences and Technology (UH-SOEST) located and successfully recovered the latter's lost ROV named Luu'kai{{cite web |url=http://www.soest.hawaii.edu/UMC/cms/h6000-rov/ |title=Lu'ukai ROV |publisher=University of Hawaii at Manoa |url-status=dead |archive-url=https://web.archive.org/web/20200225025915/http://www.soest.hawaii.edu:80/UMC/cms/h6000-rov/ |archive-date=25 February 2020}} north of Oahu at a depth of {{cvt|4,720|m}}. The drone had broken its tether and was lost on the ocean floor on 20 July 2019. To retrieve Luu'kai, the team lowered a lift elevator and Petrel{{'}}s ROV worked on the recovery procedure. Luu'kai was recovered by the joint team on 29 August 2019.{{Cite web|url=https://www.hawaiipublicradio.org/post/microsoft-co-founders-vessel-finds-lost-uh-undersea-drone|title=Microsoft Co-Founder's Vessel Finds Lost UH Undersea Drone|last=Cruz|first=Catherine|website=www.hawaiipublicradio.org|date=24 December 2019|access-date=2020-03-14}}

After finding Kaga and Akagi, Petrel crossed the Pacific in the fourth quarter of 2019 and stationed in the Atlantic Ocean to launch Deep Argo floats beginning January 2020. Through several weeks in January 2020, in the Brazil Basin of the Atlantic, Petrel and National Oceanic and Atmospheric Administration (NOAA) deployed a number of standard Navis floats (2000-m profiles), and deep SOLO floats (6000-m profiles).

As part of the Deep Argo project, a multiyear partnership between the NOAA Pacific Marine Environmental Laboratory (NOAA PMEL) and the Paul G. Allen Family Foundation, the project aimed for a final deployment of Deep Argo floats aboard Petrel. Thousands of these floats are freely drifting around the globe to measure the temperature, salinity, and turbidity of the upper ocean, at depths down to {{cvt|2,000|m|abbr=on}} and deeper to {{cvt|6,000|m|abbr=on}}.{{Cite web|url=https://sea-technology.com/paul-allen-commits-4-million-to-jump-start-deep-ocean-monitoring|title=Paul Allen Commits $4 Million to Jump-start Deep Ocean Monitoring Sea Technology magazine|date=2018-05-17|website=Sea Technology magazine|language=en-US|access-date=2020-03-11}} The Foundation committed $4 million to NOAA to help implement the Deep Argo effort.{{Cite web|url=https://research.noaa.gov/article/ArtMID/587/ArticleID/2390/Paul-Allen-visionary|title=Paul Allen: technologist, visionary, supporter of ocean science - Welcome to NOAA Research|website=research.noaa.gov|access-date=2020-03-11}}

In June 2020, Petrel had a Kongsberg EM124 1°x2° full ocean MBES installed. A sub-bottom profiler, a Kongsberg SBP 29 6° system, was also installed on the ship. Both were tested in the Atlantic Ocean, giving detailed bathymetry readings from {{cvt|400|to|4800|m|abbr=on}} depths.

On 11 June 2020, the Petrel{{'}}s Facebook page announced that the vessel was going to be moored indefinitely. The announcement read:{{Cite web|title=RV Petrel|url=https://www.facebook.com/rvpetrel/|access-date=2020-09-10|website=www.facebook.com|language=en}}

{{Blockquote|The impact of the COVID-19 crisis has changed the world for the long term in ways that we never could have imagined. As a result of operational challenges from the pandemic, R/V Petrel will be placed into long-term moorage and she will not be deployed for the foreseeable future. We were tasked with a monumental mission — discover, educate, and honor — and we're hopeful we will eventually be back in service". Robert Kraft, subsea director, said, "I am proud of the successful Petrel missions that have brought information and closure to so many families and friends of WWII heroes. I am hopeful that Petrel will eventually be back in service, supporting the collection of ocean data and science".}}

After a drydocking in Florida, Petrel sailed for Leith, Scotland, on 16 August 2020 and arrived on 3 September to be laid up.{{Cite web|url=https://www.marinetraffic.com/en/ais/details/ships/shipid:201267/mmsi:235102789/imo:9268629/vessel:PETREL|access-date=2020-09-10|website=www.marinetraffic.com|title=Petrel |archive-url=https://web.archive.org/web/20210524063500/https://www.marinetraffic.com/en/ais/details/ships/shipid:201267/mmsi:235102789/imo:9268629/vessel:Petrel |archive-date=24 May 2021}}

In October 2022, Petrel was purchased by the United States Navy for its Naval Facilities Engineering and Expeditionary Warfare Center (NAVFAC EXWC), to be operated by the American company Oceaneering International.{{Cite news |date=2023-03-22 |title=Multiple injuries after ship tips over at Edinburgh dockyard |language=en-GB |work=BBC News |url=https://www.bbc.com/news/technology-65038617 |archive-url=https://web.archive.org/web/20230322202320/https://www.bbc.com/news/technology-65038617 |archive-date=2023-03-22|access-date=2023-03-22}} The ship, plus associated spare parts, was purchased for $12,400,000.{{cite web |title=Contracts for September 29, 2022 |url=https://www.defense.gov/News/Contracts/Contract/Article/3175072/ |website=U.S. Department of Defense |access-date=24 March 2023}}

On 22 March 2023, whilst dry-docked at Imperial Dock in Leith, Edinburgh, the vessel became dislodged from her holdings in strong winds and toppled over to an angle of 45 degrees. This resulted in 33 people being injured, with 21 taken to hospital and 12 treated at the scene. Police Scotland were alerted to the incident at 8:35am local time, with Scottish emergency services declaring a major incident shortly thereafter. Several specialist medical and rescue teams mobilised during the operation including HM Coastguard, NHS Lothian medical personnel and two Scottish Air Ambulances.{{cite news |title=Leith Imperial Dock: Serious incident as ship topples over in dry dock |url=https://www.heraldscotland.com/news/homenews/23403769.leith-docks-major-incident-declared-ship-topples-dry-dock/ |work=Herald Scotland |access-date=22 March 2023}}{{cite news |last1=Davies |first1=Caroline |title=Twenty-one people taken to hospital after ship topples over at Leith dry dock |url=https://www.theguardian.com/uk-news/2023/mar/22/ship-topples-over-in-terrifying-incident-at-leith-dry-dock |access-date=22 March 2023 |work=The Guardian |date=22 March 2023}} Winds gusting between {{convert|38|and|44|mph}} were recorded around the time of the incident.

A few weeks later, Petrel was successfully righted and refloated.{{Cite web |title=Navy Research Vessel R/V Petrel Righted and Refloated |url=https://news.usni.org/2023/05/04/navy-research-vessel-r-v-petrel-righted-and-refloated}}

{{reflist}}

{{Commons category-inline|IMO 9268629}}

{{Vulcan Inc.}}

{{2023 shipwrecks}}

{{DEFAULTSORT:Petrel, RV}}

Category:2002 ships

Category:Research vessels of the United Kingdom

Category:Ships built by Fincantieri

Category:Ships built in Norway

Category:Maritime incidents in 2023

Category:Merchant ships of the Isle of Man

Category:Research vessels of the United States Navy