Overview
Marine One is the call sign of any United States Marine Corps aircraft carrying the president of the United States. It usually denotes a helicopter operated by Marine Helicopter Squadron One (HMX-1) "Nighthawks", consisting of either the large Sikorsky VH-3D Sea King or the newer, smaller VH-60N "White Hawk". Both helicopters are called "White Tops" because of their livery. Any Marine Corps aircraft carrying the vice president of the United States without the president has the call sign Marine Two.
History
The first use of a helicopter to transport the president was in 1957, when President Dwight D. Eisenhower traveled on a Bell UH-13J Sioux. The president wanted a quick way to reach his summer home, in Pennsylvania. Using Air Force One would have been impractical over such a short distance, and there was no airfield near his home with a paved runway to support fixed-wing aircraft, so Eisenhower instructed his staff to investigate other modes of transport and a Sikorsky UH-34 Seahorse helicopter was commissioned. The early aircraft lacked the amenities of its modern successors, such as air conditioning and an aircraft lavatory for use in flight.
In 1958, the H-13 was replaced by the Sikorsky H-34, which was succeeded in 1961 by the VH-3A.
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