Ten Technologies: A Brief Look at Military Evolution — Helicopters

Learn more about Vietnam War technology from the best Vietnam War books written by the heroes who served there.

By Carla Voorhees,

Defense Media Activity

This is the sixth in a series of 10 technologies integral to the United States military since World War I.

The helicopter was rapidly developed for the United States military after Igor Sikorsky, a Russian-American, found a way to compensate for the torque effect (where the body tends to rotate opposite the direction of the rotors) in the late 1930s. The first military design was designated the Sikorsky Aircraft Corporation’s R-4, and was used primarily for rescue operations performed by the Army Air Forces Air Rescue Service, starting in 1944.

Between the end of World War II and the beginning of the Vietnam War, helicopter use and technology exploded, especially by the U.S. Marine Corps. The helicopter allowed for a quick-moving, agile force that could react to enemy offensives, like airborne cavalry, and deposit troops, weapons, and supplies in the field even in difficult terrain.

Variants include the CH-47 Chinook transport helicopters, which can handle up to 19,500 lbs, and the CH-54 Skyhook – essentially a flying crane.

The U.S. Army benefits from helicopters, too, with a Program Executive Office Aviation that works exclusively on helicopters, aviation systems, UAVs, and non-standard rotary-wing aircraft.

Ten Technologies: A Brief Look at Military Evolution — Radio Equipment

By Carla Voorhees,
Defense Media Activity

This is the second in a series of 10 technologies integral to the United States military since World War I.

In the early twentieth century, radio was considered a wonder – it allowed long distance communication without wires, known as “wireless telegraphy.” Morse code was transmitted via electromagnetic waves without the need to lay miles of wires. Although there were drawbacks to the initial technology, such as interference and a lack of security, the technology evolved into the radio we know today.

The Army Signal Corps is the best-known military developer of radio technology. A list of equipment used by the Army Signal Corps can be seen here.

During World War II, radio technology evolved from simply a wireless communications tool to a hybrid approach including teletype and telephone equipment. The Army-Navy Transportable Radio Communications system (AN/TRC) was a game-changer. It could be installed much faster and with fewer personnel than traditional wire-based systems and was small enough to fit into a truck and a trailer. AN/TRC could also transmit facsimile (fax) transmissions of text, pictures, and drawings.

Additionally, during WWII, a radio technology offshoot – RADAR (essentially a tiny Doppler radio) became a critical component in the development of the proximity fuse. This allowed shells equipped with RADAR to sense the target and detonate over the target, rather than on impact, improving the accuracy of artillery fire.

Radio continued to play an integral part throughout WWII, the Korean War, Vietnam War, Cold War, and does so to this day.