Neil Alden Armstrong

Building such behemoths presented few major challenges to aviation engineers, but in other areas of flight the engineering innovations have continued. As longer range became more important in commercial aviation, turbojet engines were replaced by turbofan engines, which greatly improved propulsive efficiency by incorporating a many-bladed fan to provide bypass air for thrust along with the hot gases from the turbine. Engines developed in the last quarter of the 20th century further increased efficiency and also cut down on air pollution.

Computers entered the cockpit and began taking a role in every aspect of flight. So-called fly-by-wire control systems, for example, replaced weighty and complicated hydraulic and mechanical connections and actuators with electric motors and wire-borne electrical signals. The smaller, lighter electrical components made it easier to build redundant systems, a significant safety feature. Other innovations also aimed at improving safety. Special collision avoidance warning systems onboard aircraft reduce the risk of midair collisions, and Doppler weather radar on the ground warns of deadly downdrafts known as wind shear, protecting planes at the most vulnerable moments of takeoff and landing.

• Computers entered the cockpit and began taking a role in every aspect of flight. So-called fly-by-wire control systems, for example, replaced weighty and complicated hydraulic and mechanical connections and actuators with electric motors and wire-borne electrical signals. The smaller, lighter electrical components made it easier to build redundant systems, a significant safety feature. Other innovations also aimed at improving safety. Special collision avoidance warning systems onboard aircraft reduce the risk of midair collisions, and Doppler weather radar on the ground warns of deadly downdrafts known as wind shear, protecting planes at the most vulnerable moments of takeoff and landing.

General aviation, the thousands of private planes and business aircraft flown by more than 650,000 pilots in the United States alone, actually grew to dwarf commercial flight. Of the 19,000 airports registered in the United States, fewer than 500 serve commercial craft. In 1999 general aviation pilots flew 31 million hours compared with 2.7 million for their commercial colleagues. Among the noteworthy developments in this sphere was Bill Lear's Model 23 Learjet, introduced in 1963. It brought the speed and comfort of regular passenger aircraft to business executives, flew them to more airports, and could readily adapt to their schedules instead of the other way around. General aviation is also the stomping ground of innovators such as Burt Rutan, who took full advantage of developments in composite materials (see High Performance Materials) to design the sleek Voyager, so lightweight and aerodynamic that it became the first aircraft to fly nonstop around the world without refueling.

• General aviation, the thousands of private planes and business aircraft flown by more than 650,000 pilots in the United States alone, actually grew to dwarf commercial flight. Of the 19,000 airports registered in the United States, fewer than 500 serve commercial craft. In 1999 general aviation pilots flew 31 million hours compared with 2.7 million for their commercial colleagues. Among the noteworthy developments in this sphere was Bill Lear's Model 23 Learjet, introduced in 1963. It brought the speed and comfort of regular passenger aircraft to business executives, flew them to more airports, and could readily adapt to their schedules instead of the other way around. General aviation is also the stomping ground of innovators such as Burt Rutan, who took full advantage of developments in composite materials (see High Performance Materials) to design the sleek Voyager, so lightweight and aerodynamic that it became the first aircraft to fly nonstop around the world without refueling.

Efforts to tackle the engineering problems associated with powered flight began well before the Wright brothers' famous trials at Kitty Hawk. In 1804 an English baronet, Sir George Cayley, launched modern aeronautical engineering by studying the behavior of solid surfaces in a fluid stream and flying the first successful winged aircraft of which we have any detailed record. And of course Otto Lilienthal's aerodynamic tests in the closing years of the 19th century influenced a generation of aeronautical experimenters.

• Efforts to tackle the engineering problems associated with powered flight began well before the Wright brothers' famous trials at Kitty Hawk. In 1804 an English baronet, Sir George Cayley, launched modern aeronautical engineering by studying the behavior of solid surfaces in a fluid stream and flying the first successful winged aircraft of which we have any detailed record. And of course Otto Lilienthal's aerodynamic tests in the closing years of the 19th century influenced a generation of aeronautical experimenters.

• 1901 First successful flying model propelled by an internal combustion engine Samuel Pierpont Langley builds a gasoline-powered version of his tandem-winged "Aerodromes." the first successful flying model to be propelled by an internal combustion engine.  As early as 1896 he launches steam-propelled models with wingspans of up to 15 feet on flights of more than half a mile.

• 1903 First sustained flight with a powered, controlled airplane Wilbur and Orville Wright of Dayton, Ohio, complete the first four sustained flights with a powered, controlled airplane at Kill Devil Hills, 4 miles south of Kitty Hawk, North Carolina. On their best flight of the day, Wilbur covers 852 feet over the ground in 59 seconds. In 1905 they introduce the Flyer, the world’s first practical airplane.