Editing Lockheed P-3 Orion (section)

===United States===
[[File:P-3B DN-SC-82-02246.JPEG|thumb|A P-3B of [[VP-6]] near Hawaii]]
[[File:P-3C Orion2.jpg|thumb|A US P-3C Orion of [[VP-8]]]]
[[File:Two man replace a main landing gear tire of a plane.jpg|thumb|Changing a tire on a P-3C]]
[[File:20190401 P-3 Orion Tail 161593 Kadena AB-26.jpg|thumb|A P-3C on final approach at [[Kadena AB]] in 2019|alt=Side-view of a four-engine propeller aircraft in landing configuration.]]

Developed during the [[Cold War]], the P-3's primary mission was to localize [[Soviet Navy]] [[Ballistic missile submarine|ballistic missile]] and [[fast attack submarine]]s detected by [[SOSUS|undersea surveillance]] systems and eliminate them in the event of full-scale war.<ref>{{cite journal |last=Holler |first=Roger A. |date=5 November 2013 |title=The Evolution Of The Sonobuoy From World War II To The Cold War |journal= U.S. Navy Journal of Underwater Acoustics |pages=332–333 |url=https://apps.dtic.mil/dtic/tr/fulltext/u2/a597432.pdf |archive-url=https://web.archive.org/web/20200324114802/https://apps.dtic.mil/dtic/tr/fulltext/u2/a597432.pdf |url-status=live |archive-date=24 March 2020 |access-date=24 March 2020}}</ref><ref name=Whitman>{{cite magazine |last=Whitman |first=Edward C. |date=Winter 2005 |title=SOSUS The "Secret Weapon" of Undersea Surveillance |magazine=Undersea Warfare |volume=7 |issue=2 |url=https://www.public.navy.mil/subfor/underseawarfaremagazine/Issues/Archives/issue_25/sosus.htm |access-date=24 March 2020 |archive-date=24 March 2020 |archive-url=https://web.archive.org/web/20200324114806/https://www.public.navy.mil/subfor/underseawarfaremagazine/Issues/Archives/issue_25/sosus.htm |url-status=dead }}</ref> At its height, the U.S. Navy's P-3 community consisted of twenty-four active duty "Fleet" patrol squadrons home based at air stations in the states of Florida and Hawaii as well as bases which formerly had P-3 operations in Maryland, Maine, and California.

There were also thirteen Naval Reserve patrol squadrons identical to their active duty "Fleet" counterparts, said Reserve "Fleet" squadrons being based in Florida, Pennsylvania, Maryland, Michigan, Massachusetts (later relocated to Maine), Illinois, Tennessee, Louisiana, California and Washington. Two Fleet Replacement Squadrons (FRS), also called "RAG" squadrons (from the historic "Replacement Air Group" nomenclature) were located in California and Florida. The since-deactivated [[VP-31]] in California provided P-3 training for the Pacific Fleet, while [[VP-30]] in Florida performed the task for the Atlantic Fleet. These squadrons were also augmented by a test and evaluation squadron in Maryland, two additional test and evaluation units that were part of an air development center in Pennsylvania and a test center in California, an oceanographic development squadron in Maryland, and two active duty "special projects" units in Maine and Hawaii, the latter being slightly smaller than a typical squadron.

In [[fiscal year]] 1995, the U.S. Navy planned to reduce active-duty patrol squadrons from sixteen to thirteen—seven on the East Coast, six on the West.<ref>Peter Felsted, "Orion Hunts a Different Prey," [[Jane's Defence Weekly]], 12 November 1994, p25.</ref> The patrol squadrons planned to survive were VP-8, 10, 11, and 26 at [[NAS Brunswick]], Maine, and [[VP-5]], 16, and 45 at [[NAS Jacksonville]], Florida. The Pacific squadrons that were to be retained were VP-1, 4, 9, and 47 at Barbers' Point, Hawaii, and 40 and [[VP-46]] at [[NAS Whidbey Island]], Washington. Thus Patrol Squadrons 17, 23, 24, and 49 were to be disestablished, and the remaining units were to operate nine aircraft instead of eight, augmented by VP-30 and the nine-at-the-time USNR P-3 squadrons.

Reconnaissance missions in international waters led to occasions where Soviet fighters would "bump" a P-3, either operated by the U.S. Navy or other operators such as the [[Royal Norwegian Air Force]]. On 1 April 2001, [[Hainan Island incident|a midair collision]] between a United States Navy EP-3E ARIES II signals surveillance aircraft and a [[People's Liberation Army Navy]] [[Shenyang J-8|J-8II]] jet fighter-interceptor resulted in an international dispute between the U.S. and the People's Republic of China (PRC).<ref>{{cite web |url=https://abcnews.go.com/GMA/story?id=126584&page=1 |title='Born to Fly,' by Lt. Shane Osborn |archive-url=https://web.archive.org/web/20110129141835/https://abcnews.go.com/GMA/story?id=126584&page=1 |archive-date=29 January 2011 |website=abcnews.go.com |date=6 January 2006 |access-date=28 July 2010 |url-status=live}}</ref>

More than 40 P-3 variants have demonstrated the type's rugged reliability, commonly flying 12-hour plus missions {{convert|200|ft|m|abbr=on}} over water.{{Citation needed|date=January 2023}} Versions were developed for the [[National Oceanic and Atmospheric Administration]] (NOAA) for research and hurricane hunting/hurricane wall busting, for the [[U.S. Customs Service]] (now [[U.S. Customs and Border Protection]]) for drug interdiction and aerial surveillance mission with a rotodome adapted from the [[Grumman E-2 Hawkeye]] or an [[AN/APG-66]] radar adapted from the [[General Dynamics F-16 Fighting Falcon]], and for [[NASA]] for research and development.

The U.S. Navy remains the largest P-3 operator, currently distributed between a single fleet replacement (i.e., "training") patrol squadron in Florida (VP-30), 12 active duty patrol squadrons distributed between bases in Florida, Washington and Hawaii, two [[United States Navy Reserve|Navy Reserve]] patrol squadrons in Florida and Washington, one [[active duty]] special projects patrol squadron (VPU-2) in Hawaii, and two active duty test and evaluation squadrons.{{nu|date=April 2024}} One additional active duty fleet reconnaissance squadron (VQ-1) operates the [[EP-3 Aries]] [[signals intelligence]] (SIGINT) variant at Naval Air Station Whidbey Island, Washington.

In January 2011, the U.S. Navy revealed that P-3s have been used to hunt down "third generation" [[narco-submarine]]s.<ref>{{cite web |url=http://defensetech.org/2011/01/14/p-3-subhunters-pressed-into-service-to-find-narco-subs/ |title=P-3 Subhunters Using ASW Gear to Find Narco-Subs? |archive-url=https://web.archive.org/web/20110119025007/http://defensetech.org/2011/01/14/p-3-subhunters-pressed-into-service-to-find-narco-subs/ |archive-date=19 January 2011 |newspaper=defensetech.org |date=14 January 2011 |access-date=25 January 2011 |url-status=usurped}}</ref> This is significant because as recently as July 2009, fully submersible submarines have been used in smuggling operations.<ref>Page, Lewis. [https://www.theregister.co.uk/2010/07/06/true_sub_captured_from_drug_smugglers/ "First true submarine captured from American drug smugglers."] {{Webarchive|url=https://web.archive.org/web/20101105220635/http://www.theregister.co.uk/2010/07/06/true_sub_captured_from_drug_smugglers/ |date=5 November 2010 }} ''The Register,'' 6 July 2010. Retrieved: 25 January 2011.</ref> As of November 2013, the US Navy began phasing out the P-3 in favor of the newer and more advanced Boeing P-8 Poseidon.

In May 2020, [[VP-40 (1951-present)|Patrol Squadron 40]] completed the transition to the P-8, marking the retirement of the P-3C from U.S. Navy active duty service. The last of the active-duty P-3Cs, aircraft 162776, was also delivered to the [[National Museum of Naval Aviation|Naval Aviation Museum]] in [[Pensacola, Florida]]. Two Navy Reserve squadrons, [[Air Test and Evaluation Squadron 30]] and One Active duty Squadron ([[VQ-1]]) continued to fly the P-3C.<ref name=":0">{{cite web |url=https://www.navytimes.com/news/your-navy/2020/06/04/fair-winds-and-following-seas-to-the-navys-p-3c/ |title=Fair winds and following seas to the Navy's P-3C |newspaper=[[Navy Times]] |date=4 June 2020 |first=Geoff |last=Ziezulewicz}}</ref> In February of 2025 VQ-1 retired their final EP-3E Aries II and P-3C, leaving VX-30 and VXS-1 as the only squadrons operating the P-3 in U.S. Navy service.<ref>{{cite web | url=https://scramble.nl/military-news/sundown-for-fleet-air-reconnaissance-squadron-one | title=Sundown for Fleet Air Reconnaissance Squadron One | date=18 February 2025 }}</ref>