A little more than a century ago, Wilbur and Orville Wright achieved the first powered, sustained, and controlled flight of an airplane, an experiment that changed the world. However, the principles of flight were established well before then, studied and tested by explorers and inventors worldwide. From the ancient Greek inventor Archimedes to the Wright brothers and beyond, humankind has sought to unlock the secrets of flight, finding a way for humans to defy gravity and slip the bonds that keep us earthbound. The History of Flight examines the origins of this quest, explains the mechanisms by which flight is possible, and tells the story of how aviation has evolved.
The earliest forays into human flight were in balloons. Balloon flight is possible because of buoyancy, which allows a balloon to carry a weight that is less than or equal to the difference between the weight of the balloon (and its enclosed gas) and that of the air that it displaces. A balloon’s buoyancy can be controlled by changing the amount of gas in the envelope (in the case of a gas balloon) or by changing the temperature of the air within the envelope (in the case of a hot-air balloon), thereby changing its weight relative to the amount of air it displaces. In addition to an envelope and a heat source, hot-air balloons designed for travel have a basket, or gondola, for the passengers and instruments, and an air-release system for controlled descent and landing.
The Montgolfier brothers of late 18th-century France were the fathers of hot-air ballooning. In a smallish balloon of their own creation—with an envelope of cloth and paper enclosing air heated by burning straw—they made the first successful unmanned balloon flight in June of 1783. In November of that year, fellow Frenchmen Jean-François Pilâtre de Rozier and François Laurent, marquis d’Arlandes achieved a 10-mile manned flight over Paris, witnessed by France’s King Louis XVI and American inventor and statesman Benjamin Franklin.
Over the next two centuries, fuel sources for hot-air balloons moved from the Montgolfiers’ original burning straw to include coal gas, petroleum, and propane. Envelope design evolved as well, moving from cloth and paper to include silk and nylon, and, in the case of super-pressure balloons, polyester. Propane burners and nylon or polyester envelopes remain popular in hot-air ballooning today.
Ballooning in the 20th century pushed the boundaries of the craft. The development of pressurized suits and cabins allowed for high-altitude flight. High-altitude balloons have specific practical applications, for example, aerial photography and cosmic ray research. Modern-day adventurers pushed the limits of ballooning, including Steve Fossett, who made the first solo balloon flight around the world in 2002. Ballooning also has become a popular leisure activity. Commercial hot-air balloons can carry as many as 20 passengers.
Flight via airships enjoyed a brief popularity in the first decades of the 20th century. There are three types of airships. Non-rigid airships, commonly called “blimps,” are made of material similar to that used for the envelopes of gas balloons. Rather than a basket, however, an airship envelope is attached to a car that has rudders and a set of propellers driven by engines. Semi-rigid airships also are similar to blimps but have a metal keel running the length of the balloon’s base.
Finally, rigid airships are made of a fabric envelope supported on a frame of metal. This type of aircraft saw some success as a means of transport in the 1920s and ’30s. Dirigibles designed by (and named after) Ferdinand von Zeppelin were used for military purposes during World War I by both Germany and the Allies. The famous Hindenburg—the largest dirigible ever constructed—made a series of cross-Atlantic passenger trips in the 1930s, culminating in a spectacular crash on May 6, 1937, in New Jersey. The ship ignited and burned upon landing, killing 36 of its 97 occupants.
Dirigibles became obsolete not only because of their limitations and safety concerns, but also due to the advancements in heavier-than-air craft, or airplanes. At the dawn of the 20th century, three obstacles to airplane flight remained—lift, propulsion, and control. The solution to the first problem, lift, lay in the design of wings for the aircraft. The earliest aircraft wing designs mimicked the flapping motion of birds. In the early 1880s, Englishman George Cayley designed an aircraft wing patterned after the shape, rather than the motion, of a bird’s wing, which led to the creation of the first cambered, or arched, airplane wing. German mechanical engineer Otto Lilienthal compiled data on Cayley’s design, which led him to build and successfully fly a number of gliders. The Wright brothers used Lilienthal’s data in their plane designs.
The next obstacle was propulsion. Until the late 19th century, machines with adequate power to propel an aircraft were too heavy. By the end of the century, however, internal-combustion engines had solved this problem. The Wright flyer of 1903, Orville and Wilbur’s first plane, had a lightweight 12-horsepower, four-cylinder engine designed by the Wright brothers’ machinist, Charles Taylor.
Regarding the matter of control—the last problem to be solved—a successful flight system had to take into account full control over the balance and steering of the airplane in all three dimensions: roll (the banking of the plane), pitch (the direction of the nose up or down), and yaw (the direction of the nose to right or left). The Wrights’ solution included “wing-warping,” or changing the angle of the wings to control the plane’s roll, an elevator to control pitch, and a rudder to control yaw. In 1903, having surmounted the roadblocks to construction of a controllable flying machine, the Wright brothers debuted their plane at Kill Devil Hills, near Kitty Hawk in North Carolina. The age of airplane travel had begun.
Europe eagerly embraced airplane research and development in the years leading up to World War I. During the war, investors began to explore the nonmilitary applications of planes as a means of travel. Surplus military planes were employed for passenger travel and mail delivery in the postwar years. Competition, both commercial and personal, led to longer flights, across continents and oceans, with European and American aviators trying to best duration and speed records through the 1920s and ’30s. Government-subsidized airlines were founded in Britain and France; operations in the Netherlands, Germany, and the Soviet Union weren’t far behind.
Meanwhile, in the United States, decommissioned military planes were at first used primarily for airmail service. The United States encouraged private development of its airplane industry, and the competition among private entrepreneurs ultimately improved the design and safety of planes. Boeing and the Douglas Aircraft Company, with its DC line, were dominant players in the burgeoning U.S. airplane industry.
With the arrival of passenger air travel came the need for regulation and safety standards. In the United States, a number of organizations were created to investigate airplane accidents and determine their causes.
In the 1920s, a private organization called the Daniel Guggenheim Fund for the Promotion of Aeronautics conducted experiments with instrumentation and “blind flight,” supported advances in the meteorological sciences, and established university programs in aeronautical engineering.
World War II temporarily stalled the private air industry, as airplanes were appropriated for military use. The United States provided nearly all of the planes for the Allies during the war, due mainly to the reliability of planes such as the DC-3, as well as the country’s ability to meet production quotas. The U.S. Army Air Force Air Transport Command (ATC) created airfields, communication centres, and weather forecasting stations around the world. Using the ATC as a model, the International Civil Aviation Organization (ICAO) was founded after the war, in 1947. An arm of the United Nations, the ICAO standardized aviation terminology, safety procedures, and equipment, and established English as the universal language for global flights.
Airlines flourished after the war. Flying became the premiere mode of travel, with airlines booking more passengers than railways and ships by the 1950s. Due to an uptick in business, fares were lowered and flights became an affordable means of transportation for the average citizen. The use of aircraft for personal, business, and “utility” (surveying, crop dusting, etc.) purposes also increased. Together, all modes of air transportation not connected to military or scheduled airline flights were referenced under the term “general aviation.”
As piston engines reached the limits of their performance, airplane designers turned to jet engines, which were simpler in design, longer-lasting, and more efficient at high altitudes. Jet engines had been around since the late 1930’s but came into common usage by the 1950s. The switch to jet engines necessitated changes to the design of airplanes. Airlines restocked their fleets with jet planes such as the American DC-8 and the French Caravelle. Jet technology proved expensive, so booking more passengers was required to make it economically feasible for the airlines to make the switch. Other aviation changes and improvements during the “jet age” included the addition of the “black box” data recorders and satellite navigation.
Other means of air travel were developed or refined in the 20th century, including hang gliders and ultralight airplanes. There also were aircraft that operated using vertical lift. The gyroplane was first successfully launched in 1907 by the Brequet brothers in France. It only rose two feet off of the ground and was tethered due to its lack of control, but it was successful enough to serve as something of a prototype. From there two distinct machines were created—the autogiro and the helicopter.
Using motor-driven horizontal rotors, helicopters could take off vertically, thus eliminating the need for runways. However, these machines required a more developed structure and finely tuned control than a plane. By 1941, the first modern helicopter had appeared, complete with a three-blade main rotor for lift and a small vertical tail rotor to counteract torque. The development of controls—collective pitch, throttle, antitorque, and cyclic-pitch—allowed for smooth liftoffs, flights, and landings. Modern helicopters also feature retractable landing gear, navigational equipment, and instruments similar to those in airplanes.
Before World War II, planes only needed runways of about 2,000 feet—and those were rarely paved. Airports were located near city centres and frequently near water as well, for seaplane landings. Today’s 100 or so large hub airports around the world are vast operations, with extensive space dedicated to paved runways and operational facilities. More than half of these larger airports are located in the United States.
The operations of an airport have two basic divisions—the airside and the landside. Airside facilities include the runways and plane taxi areas, air traffic control and navigation, emergency services, and maintenance. Landside facilities include the passenger terminal, cargo areas, and access roads. Airports are often managed by independent agencies licensed by the government, although many of the services within are provided by other agencies, public and private. When selecting a site for a new airport, location and the airport’s effect on surrounding areas are carefully considered. Accessibility, noise, and terrain are some of the factors that determine airport placement.
In response to a number of hijackings and other terrorist threats to commercial aircraft during the 1960s and ’70s, the International Civil Aviation Organization issued several recommendations aimed at air travel. However, compliance with the ICAO measures varied. Essentially the only solid standards were that passenger belongings were screened, and the public was denied access to certain areas. Since the attacks of September 11, 2001, however, airport design and operation have undergone major changes. Scrutiny of passengers and their belongings has intensified, creating a massive expansion of security personnel and equipment, and necessitating that passengers arrive well ahead of scheduled flights to allow enough time for screening. Additional attention has been paid to locating parking and loading areas outside of the airport, to reduce the damage caused by vehicular explosions.
Human life has been irrevocably altered since the advent of flight. Before airplane travel was common, an individual who moved far from home might never have returned. Mail sent long distances could take weeks to arrive. Nations at war could wait as long as a month for supplies and troops to arrive. Air travel has made our world more accessible, and thus more interdependent. The History of Flight details the fascinating journey that has brought the nations and peoples of the world closer together.