CH-46 Sea Knight // USMC helicopterBoeing CH 46 Sea Knight helicopter model. The CH 46 is used by the Marine Corps to provide all weather, day or night assault transport of combat troops, supplies and equipment. Troop assault is the primary function, and the movement of supplies and equipment is secondary. Additional tasks may be assigned, such as combat support, search and rescue, support for forward refueling and rearming points, aeromedical evacuation of casualties from the field