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Via Allyn Hinton
Marine Medium Helicopter Squadron 561 was activated 31 January 1967 and was assigned to Marine Aircraft Group 56. It's assigned mission was to provide refresher training to Marines who would be joining UH-34D squadrons in Vietnam. It also was called on to conduct local Search and Rescue missions, provide VIP transport, and other commitments as required by local commands.
Due to a lack of personnel and aircraft to man the squadron, HMM-561 remained in cadre status until formally activated 8 May 1967. At this time there were 62 Officers and 242 Enlisted assigned to the squadron. 24 UH-34Ds were also assigned at this time.
In January 1969, WestPac requirements for UH-34s were curtailed as the UH-34D began to be phased out and replaced by the CH-46. Squadron strength dropped to 26 Officers, 287 Enlisted, and 12 aircraft. HMM-561 conducted a 12-aircraft flyby of El Toro and Santa Ana on 14 October 1969. On 27 October 1969,HMM-561, the last operational UH-34D squadron in the Fleet Marine Force, was deactivated.
On December 2, 2010, VMM-561 was re-activated, becoming the third West Coast MV-22 squadron. According to the 2010 Marine Corps Aviation Plan, VMM-561 will initially be assigned to MAG-16, then relocate, probably to Okinawa, in 2013/14, although according to squadron personnel, "Pale Horse" may be relocating to Hawaii instead.
Activated 31 January 1967 as Marine Medium Helicopter Squadron 561, Marine Aircraft Group 56, 3d Marine Aircraft Wing, FMF
Officially activated 8 May 1967
Deactivated 27 October 1969.
Reactivated 2 December 2011 as Marine Medium Tiltrotor Squadron 561, Marine Aircraft Group 16, 3d Marine Aircraft Wing, FMF