Marines with the 31st Marine Expeditionary Unit's Maritime Raid Force perform Helocast training at Kin Blue Beach, Okinawa, Japanbr br During Helocast, a Combat Rubber Raiding Craft is launched from the rear of a rotary-wing aircraft, followed by Marines and Sailors who jump from the aircraft and board the CRRC to perform amphibious reconnaissance missions. The 31st MEU, the Marine Corps’ only continuously forward-deployed MEU, provides a flexible force ready to perform a wide range of military operations (U.S Marine Corps Motion Imagery by Lance Cpl.