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via BJ Sigman
Marine Medium Helicopter Training Squadron 402 was activated on 30 June 1969 at New River, NC, and assigned to Marine Helicopter Training Group 40. The mission of the squadron was to provide transitional training to new CH-46 pilots, and refresher training for pilots returning to the type. The squadron also used modified CH-46s to help train new AV-8 "Harrier" pilots
HMMT-402 deactivated on 1 May 1972. Personnel and aircraft were used to form HMT-204
Activated 30 June 1969 as Marine Medium Helicopter Training Squadron 402, and assigned to Marine Helicopter Training Group 40, 2d Marine Aircraft Wing, Fleet Marine Force Atlantic.
Deactivated 1 May 1972.