Their distinctive engines and rotors can be heard above the din of snarled traffic and the scream of sirens at a traffic accident. They're often in news stories from the White House to war zones. In fact, helicopters have become so much a part of contemporary life that their unique design and functions are hardly noticed anymore!

A helicopter is an aircraft that is lifted and propelled by one or more horizontal rotors, each rotor consisting of two or more rotor blades. Helicopters are classified as rotorcraft or rotary-wing aircraft to distinguish them from fixed-wing aircraft because the helicopter achieves lift with the rotor blades, which rotate around a mast.

A French inventor, Gustave de Ponton d'Amecourt in 1861, first conceived the helicopter. He coined the French name hélicoptère, from Greek words, helix/helik meaning "spiral" or "turning" and pteron meaning "wing." Although helicopters were developed and built during the first half-century of flight, it wasn't until 1942 that a helicopter designed by Igor Sikorsky reached full-scale production. Sikorsky's design, with a single main rotor balanced by an anti-torque tail rotor, became the worldwide standard for helicopter design.

A helicopter has a great advantage over a fixed-wing aircraft because it doesn't need forward movement to generate lift. This means it can take off and land vertically without a runway. It also can hover over one area more efficiently than other forms of vertical takeoff and landing (VTOL) aircraft. Its main drawback in comparison to fixed-wing aircraft is speed. In other words, what a helicopter loses in speed it makes up for in vertical maneuverability.

Helicopters were initially deployed as a military aircraft. They were first used extensively in the Korean War, where they often served as flying ambulances to bring wounded soldiers from the front back to mobile army surgical units behind the lines. Helicopters' use as military craft was greatly expanded during the Vietnam War, when they not only served again as flying ambulances but also as gun ships to fire on enemy positions.

Their wartime uses prompted civilian and business functions for helicopters as well. In fact, "helicopters for sale" ads can be found in both print and online publications.
 
Helicopters are used today by law enforcement agencies for both patrol and pursuit. The flying ambulance concept of wartime was transformed into a civilian function in the 1980s. Today every major city has a "Flight for Life" flying ambulance service that brings seriously injured or ill patients to area hospitals.

Business uses for helicopters have expanded far beyond their military capabilities. Helicopters now serve to transport business executives around urban centers where traffic congestion means precious minutes lost in traffic. Helicopters have become flying taxis, bringing passengers from busy airports to downtown hotels or company headquarters. Some corporations and news organizations keep their own helicopters and pilots on standby for when an important event occurs.

Helicopters also are used for recreation, such as flying tours for sightseers and the practice of accessing remote mountain slopes for "heli-skiing."  Think of all the new business opportunities that await if you decide to jump at the chance when you do find a helicopter for sale!