In October 1954, HMR-261 embarked its HRS helicopters on the aircraft carrier USS Saipan and sailed for Haiti where they flew humanitarian assistance/disaster relief missions following Hurricane Hazel.

[6][7] On 15 May 1962 in response to the defeat of Royal Lao Army in the Battle of Luang Namtha in early May by People's Army of Vietnam and Pathet Lao forces, it appeared that a communist invasion of northern Thailand was imminent and the Kennedy Administration ordered US combat forces into Thailand to deter any attack.

[10] Returning to MCAF New River, HMM 261 was deployed to the southern United States during the Civil Rights Movement to support freedom marches in the spring of 1963.

[11] In mid-July the squadron suffered its first aircraft loss in a non-fatal accident 37 miles (60 km) southwest of Da Nang.

The squadron again departed MCAS New River on May 18, 1965 finally arriving at Kadena Air Base in early June.

[15] On June 21, 1965 the squadron was flown to Da Nang Air Base where it replaced HMM-163 and was assigned to Marine Aircraft Group 16 (MAG-16).

[18] At the end of August, MAG-16 moved to the newly completed Marble Mountain Air Facility east of Da Nang.

[21] In December the squadron supported Operation Harvest Moon transporting Marines and Army of the Republic of Vietnam (ARVN) troops.

In October 1983, the squadron had just departed Naval Base Norfolk aboard USS Guam heading toward Beirut, but received word to divert to the Caribbean for the invasion of Grenada, codenamed Operation Urgent Fury.

While providing close air support to Army forces, two AH-1T Cobras were shot down resulting in three squadron pilots being killed.

While stationed off Beirut, the squadron conducted a variety of missions in support of the 22nd Marine Amphibious Unit located ashore, U.S. 6th Fleet and the Department of State (flying diplomats to/from the various meetings and evacuating over 800 American and Lebanese citizens to safety.)

In 1990, the squadron took part in Operation Sharp Edge, which consisted of the evacuation and protection of American citizens in Liberia.

On 15 April 1997 the squadron prepared for a pending Noncombatant Evacuation Operation (NEO) in the country of Zaire, leaving behind a detachment of four CH-46s and two UH-1Ns to board USS Ponce.

The squadron continued to perform direct support missions in the form of casualty evacuation, command and control (C&C) standby, general support, re-supply, troop movements, VIP lifts and tactical recovery of aircraft and personnel (TRAP)/Quick Reaction Force (QRF) during the day and night.

During the deployment, HMM-261 successfully completed over 2,000 Aviation Support Requests (ASRs), transported 8,358 passengers and 815,274 lb of cargo, flew 3,058.2 hours and executed 1,941 sorties, with zero combat casualties or loss of any aircraft.

[26] The squadron finished its latest tour in Iraq in late March 2006, accomplishing 1,845 sorties and over 3,000 combat flight hours providing medevacs and close air support.

The unit was considered enhanced (E-CasEvac) due to the V-22 Osprey’s operational speed and distance superiority over the US Army’s UH-60 Blackhawks (Dustoff) and British CH-47 Chinooks.

[32] On 11 April 2012, a squadron MV-22 crashed near Agadir, Morocco, during a joint training exercise after taking off from USS Iwo Jima.

A Marine Corps investigation later deemed the crash was due to pilot error, not a mechanical or safety problem.