The Boeing Vertol CH-46 Sea Knight helicopter is one of the largest helicopters in the U.S. Navy and U.S. Marine Corps inventory. The unique tandem-rotor design of the Sea Knight permits increased agility and superior handling qualities in strong relative winds from all directions, allowing, in particular, rapid direction changes during low airspeed maneuvering. This capability has resulted in the safe, efficient and graceful transfer of many millions of tons of cargo and many thousands of passengers over the years.
The CH-46D Sea Knight helicopter is used by the U.S. Navy for shipboard delivery of cargo and personnel. The CH-46E is used by the Marine Corps to provide all-weather, day-or-night assault transport of combat troops, supplies and equipment. For the Marine Corps, the primary mission is assault transport of combat troops, supplies, and equipment during amphibious and subsequent operations ashore with cargo movement 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 and recovery of aircraft and personnel.
Originally designated HRB-1, the first flight of the Sea Knight was in August of 1962. The designation was changed to CH-46A Sea Knight, which was first procured in 1964, and served in Vietnam. The CH-46A Sea Knight was upgraded with weapons and armor, along with higher-powered engines to create the CH-46D model. A further upgrade to the CH-46E came with increased power and fuel capacity. The last newly manufactured CH-46 was built in 1971.
Boeing Vertol CH-46 and UH-46 Sea Knight Helicopters
CH-46A Sea Knight is a twin-turbine powered, dual-piloted, tandem rotor helicopter designed by Vertol, later acquired by Boeing. It can carry 25 combat-loaded Marines, or can be outfitted to carry litters in the MedEvac role. It has the fuel endurance to stay airborne for approximately two hours, or up to three hours with an extra internal tank. The CH-46 Sea Knight has the ability to land and taxi in the water in case of emergency, and is able to stay afloat for up to two hours in two-foot seas.
With protruding side wheels, a nose-up attitude on the ground, and an affinity for water, the CH-46 Sea Knight helicopter earned the affectionate nickname "Phrog" among Marines and Navy personnel.
CH-46 Sea Knight Helicopter Specifications and Performance
45 ft. 3 in.
16 ft. 8 in.
24,300 lbs. max
Two 1,770 hp GE T58-GE-16 turboshaft
CH-46As from Medium Marine Helicopter Squadron (HMM) 265 carries Marines into action north of Phu Bai, South Vietnam, during Operation Hastings, 1966.
USMC CH-46E Sea Knight helicopter operating in Somalia.
Two U.S. Navy CH-46D Sea Knights from the "Gunbearers" of Helicopter Support Squadron One One (HC-11) pass each other during a Vertical Replenishment at sea involving the USS Carl Vinson (CVN 70) and the combat support ship USS Sacramento (AOE 1), 16 November 2002.
CH-46 Sea Knight helicopters in training exercise with ground troops.
CH-46 Sea Knight helicopter retrieving diver from the sea.