Modern Airplane Technology: 1950-1999

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Modern Airplane Technology: 1950-1999

Overview

From the moment Orville and Wilbur Wright (1871-1948 and 1867-1912, respectively) took their famous flight at Kitty Hawk, North Carolina, the world fell in love with the idea of the airplane. But man's fascination with flight goes back even further. As early as ancient Greece, people gazed in wonder at birds' flight, wishing they too could reach those soaring heights. Of course, for the mythological figure Icarus that wish turned fatal when he flew too high and too close to the sun; the wings his father had created out of feathers and wax melted, sending him crashing to his death.

Background

Many times throughout history, man has tried to copy birds' flight and failed. Leonardo da Vinci (1452-1519) sketched flying machines in the 1500s and even made some models. The first successful flights, however, were not taken until the early 1780s, and they were not in flying machines but in hot-air balloons. In the late 1850s balloons were enhanced with steam engines to create airships.

In the 1800s the aeronautical pioneer Sir George Cayley (1773-1857) solved many of the technological questions that airplane flight posed. In 1853 his glider was the first aircraft to take a man into the air. But credit for the first sustained flight belongs solely to the Wright Brothers, who by 1905 could keep their plane airborne for a distance of more than 20 miles (32 km). The next three decades saw numerous improvements to the airplane and the distances that could be flown.

World War I called for more durable and maneuverable planes, ones capable of speeds in excess of 130 miles per hour (209 kph). In 1927 aviator Charles Lindbergh (1902-1974) took his much-celebrated flight, crossing the Atlantic from New York to Paris in just under 34 hours in his specially designed plane, The Spirit of St. Louis. In 1932 Amelia Earhart (1898-1937) became the first woman to cross the Atlantic alone, only to disappear five years later while attempting to cross the Pacific.

In the 1920s and 1930s planes became bigger, stronger, and faster, reaching speeds of up to 300 miles per hour (483 kph). But the turning point came in the late 1930s with British engineer Frank Whittle's (1907-1996) invention of the jet engine, which used a mixture of fuel and air to create a powerful forward thrust. The first flight of a turbojet aircraft came with the Heinkel HE-178 in 1939. Suddenly, airplanes could fly at more than 500 miles per hour (805 kph) and the aerotechnology race had begun.

Impact

Airplane production during World War II numbered in the tens of thousands across the United States, Great Britain, Germany, Russia, and Japan. But because such a large number of planes was required for the war effort, the emphasis was on building conventional propeller planes, rather than jet-powered ones. Although the jet engine was faster and more powerful, its development was essentially put on hold during the 1940s. After the war, the jet needed numerous refinements before it was ready to be used commercially.

The first jet passenger service was available in May 1952 with the launch of the British De-Havilland DH 106 Comet. The new aircraft was able to cut travel time in half from that of the previous piston-engine planes. The Comet offered a smooth, quiet flight with a pressurized cabin that allowed it to be flown in all types of weather conditions. The Comet, proved short-lived, however when it fell victim to several accidents. In 1958 a revised version, the Comet 4, was introduced. It could accommodate up to 44 passengers with a four-person crew and had more commercial success than its predecessor.

The first truly successful passenger airplane was the Boeing 707-121, which took its inaugural flight in 1954. Its earliest incarnation was powered by four jet engines, each producing 13,000 pounds of thrust. The wing span was 130 feet (40 m) across, and it could cruise at speeds of 585 miles per hour (941 kph). The 707 held 189 passengers and by 1958 was able to make nonstop flights across the Atlantic. The jet age was inaugurated on October 26, 1958, with a flight from New York to Paris on a Boeing 707-121. Six weeks later came the first commercial jet flight in the U.S., from New York to Miami.

By the mid 1950s the number of passengers traveling annually was multiplying. Part of this rise in air travel was a result of the reduced cost of flying. In 1929 the cost per passenger mile was 12 cents as compared with 5.1 cents more than a decade later. The number of people traveling jumped from 2.5 million in 1937 to 45 million in 1952 and 90 million by 1957.

There were also advancements made to jet fighter aircraft in the 1950s. Jet planes used in the Korean War (1950-1953) achieved much greater speeds than those used in World War II. Over the next decade jets were able to fly at twice the speed of sound (Mach 2). Bomber and transport jet aircraft were also able to fly at supersonic speeds. The most impressive, however, was the air-launched X-15, developed by the National Advisory Committee for Aeronautics (NACA) and debuted in the early 1960s. Dropped from the B-52 bomber, this impressive machine could travel at speeds of up to Mach 6.04—over 4,000 miles per hour (6,437 kph)—and at heights of more than 67 miles (108 km) above the earth.

Aircraft instrumentation and automation also evolved significantly throughout the years following World War I. While early pilots had to rely on a magnetic compass, barometric altimeter, and an anemometer to indicate airspeed, subsequent airplanes saw numerous technological advances. From World War II until the mid-1960s, radio altimeters, weather radar, alarms for fuel, temperature and landing-gear status, as well as airspeed and altitude indicators were added. The 1950s saw the first automatic pilots, which were able to maintain speed and direction. Between 1965 and 1980, improvements included mechanized flight directors, automatic landing systems, and digital computers for monitoring the status of hydraulic and electrical systems. Several digital displays were added in the 1980s as well as moving-map displays, collision-avoidance systems, and flight-management systems. In the 1980s and 1990s global positioning navigation systems were able to guide airplanes.

In the 1960s two more successful Boeing models were released. The 727, launched in February 1963, carried 189 passengers and went on to become the second bestseller of all time. In 1967 the most successful jet of all was introduced—the two-engine Boeing 737, which would make up close to a quarter of all U.S. commercial airplanes by the 1990s.

The introduction of large, jet-powered passenger aircraft in the 1960s ushered in a new era for air travel. In early 1969 Boeing introduced its jumbo jet airliner, the first in its 747 series. The most remarkable thing about the plane was its enormous size, making it tower over every other airplane that came before it. The 747 boasted a 185-foot-long (56 m), 20-foot-wide (6.1 m) passenger cabin, which could seat eight or ten people across with plenty of headroom and comfortable seating. The first 747s went into service on Pan American's New York-to-London route in January 1970 with 324 passengers. Over the next two decades the company added eight models to its fleet of 747s and made significant improvements to the design each year.

In 1970 the McDonnell Douglas DC-10 was introduced as a competitor to the 747. This powerful plane could carry up to 380 passengers and traveled at 587 miles per hour (945 kph). By 1974 more than 90 percent of flights were taken on jet aircraft. Then in 1976 came a dramatic new entry into the field of flight—the British-French Concorde, which was able to travel at twice the speed of sound (1,320 mph/2,124 kph). Unfortunately, the Concorde, never saw widespread commercial use because of the high cost of constructing and operating the aircraft.

The early 1980s saw the release of Boeing's twin-engine 757 and 767 models, which were more fuel efficient and filled the gap between small planes and the enormous 747. In the 1990s McDonnell Douglas introduced its MD-11, which was longer and more aerodynamic than the DC-10. In 1994 Boeing countered with its 777 model, which could carry between 292 and 500 passengers and used two Pratt and Whitney engines that could generate over 70,000 pounds of thrust. The 777 was the first plane to be built entirely by computer blueprint. It also achieved the lowest passenger-per-mile cost and the greatest fuel efficiency of any passenger jet.

In the late twentieth century the emphasis in jet building was not only to improve passenger safety but to accommodate a growing number of travelers and to meet the insatiable need for greater speed and reduced travel time. New frontiers in aeronautic technology promise to take man to greater speeds and heights than ever before experienced.

STEPHANIE WATSON