Category FLIGHT and M ОТІOIM

he term air traffic refers to all air­craft in the air, about to fly, or just landed. Air traffic control is per­formed by people on the ground whose job is to ensure air safety at all times. Safety is a matter of concern for all fliers, whether they are piloting private airplanes, military jets, or airliners. Pilots have the final responsibility for the safety of any aircraft, but they must also follow instructions given by con­trollers on the ground.

Air traffic controllers make sure that aircraft of all sizes move safely around in the sky. Their work is of special importance around airports, where the sky is often crowded with airplanes. Air traffic control makes sure that planes taking off and landing do so in a safe, orderly, and efficient manner.

From the 1940s to the 1960s, U. S. engi­neers built a series of research airplanes to explore supersonic flight. These craft included the Bell X-1, Bell X-2, Douglas Skyrocket, and X-15—all were record breakers. Their flights helped engineers design supersonic jet fighters and manned spacecraft. The British Fairey Delta 2 (FD-2) set a world airspeed record of over 1,000 miles per hour (1,609 kilometers per hour) in 1956. The small FD-2 had the same delta wings

SECRET EXPERIMENTATION

Research flying is often secret. Developed in secret between 1975 and 1982 by Lockheed for the U. S. Defense Advanced Research Agency, the F-117 Nighthawk was in U. S. Air Force service years before it was revealed to the public.

Phantom Works, a project division of McDonnell Douglas (now part of Boeing), tested a different aircraft, the Bird of Prey, from 1996 to 1999. Termed an "invisible airplane," the Bird of Prey was hard to detect because of its shape, the way it was painted, and stealth specifications similar to those of the F-117.

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and drooping nose made familiar by Concorde in the 1980s.

Not all experimental airplanes fly higher or faster. The Altus is a civilian version of the military Predator, a U. S. drone used after 2000 in wars in Afghanistan and Iraq. Altus carries scientific instruments to sample the atmosphere, flying at only 80 miles per hour (129 kilometers per hour), but it is able to stay in the air for up to 24 hours. The Proteus airplane can also stay in the air for up to a day. It is designed by Burt

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Rutan, innovative designer of Voyager, an airplane that flew nonstop around the world (in 9 days) in 1986. Rutan also produced SpaceShipOne, the world’s first successful private spacecraft.

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SEE ALSO:

• Bell X-1 • Concorde • Engine

• Glider • Jet and Jet Power • Kitty Hawk Flyer • Rocket • Wright,

Orville and Wilbur

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Airports have fuel stores and hangars, which are like giant garages for air­planes. Hangars are also workshops in which aircraft can be serviced or repaired between flights. Other areas of the airport include the aircraft parking area, or loading apron. Here, a plane is refueled, and airport workers load cargo, baggage, and supplies.

Airports that handle passengers have passenger terminals of various sizes. Airports lease space to airlines for offices, ticket counters, and baggage areas. They also rent space to restau­rants, stores, car rental agencies, and other businesses within the airport.

The airport management may also run parking lots. Most big airports have
huge parking zones around the airport for short-stay and long-stay parking and for car rentals.

Large airports have separate cargo terminals for incoming and outgoing cargo. Airfreight often needs quick, careful handling, because it may include delicate equipment or foods and flowers that spoil quickly. Many airliners use big cargo planes with wide-opening doors into which containers and packages are loaded from forklift trucks and elevated loading bays. Security is strict, because airfreight often includes such high-value items as bank bonds or gold.

Aircraft use an instrument called an altimeter to measure altitude. Airplanes have two different types of altimeters. The pressure altimeter measures a plane’s altitude above mean sea level. As an airplane climbs higher in the atmos­phere, the air pressure falls. Measuring the air pressure shows how high the plane is. A pressure altimeter, or baro­metric altimeter, is accurate to within about 20 feet (6 meters).

MEASURING ALTITUDE WITH SATELLITES

Airliners fitted with satellite naviga­tion can use it to measure altitude. Radio signals received from naviga­tion satellites are used to measure the distance between the plane and the satellites. (The positions of the satellites used are precisely known.) Signals received from three satellites enable a plane to determine its posi­tion on a map. Adding a signal from a fourth satellite also enables the plane to figure out its altitude.

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As an airplane descends for landing, however, it is more important to know its height above the ground than its pressure altitude. The radio altimeter is switched on when a plane descends below 2,500 feet (762 meters). The altimeter aims radio waves at the ground and measures the time it takes for them to reach the ground and travel back up to the airplane. It uses the measurement to calculate the distance between the plane and the ground. The radio alti­meter can measure a plane’s height above the ground to within about 2 feet (0.61 meters).

SEE ALSO:

• Air and Atmosphere • Pressure

vionics is the name for an air­craft’s electronic equipment and electrical systems. Avionics have become so important in modern aviation that they can account for more than half the multimillion-dollar price of a modern aircraft.

Avionics Development

Until the 1940s, the most complicated electronic equipment carried by any air-

О Sensors constantly monitor for problems and are crucial to safety in spaceflight. These NASA astronauts and technicians are examining a sensor system installed on the Space Shuttle Discovery in 2005. The system, a long boom with camera and lasers on the end, is used to inspect the Space Shuttle’s heat shield for damage while in space.

craft was probably a radio. Then radar was developed to detect aircraft a long distance away. Radar soon became small enough and light enough to be carried by aircraft. The amount of electronic equipment in aircraft increased rapidly. The word avionics has been used to describe an aircraft’s electronic systems since the 1970s.

At first, an aircraft’s avionics were a collection of separate electrical and electronic circuits, each with its own wiring. Today, all the various circuits and systems work together, connected to an information highway called a data – bus. The databus carries information around an aircraft’s avionics systems in the same way that a computer’s databus carries information between the key­board, processor, memory, monitor, and other parts.

A lot of work goes into making sure that the different pieces of avionics equipment will work together in an aircraft without inter­fering with each other. This process is called systems integration. A big project, such as a new airliner, often has hundreds of engineers working on systems integration.

By late 1947 the X-1 was ready to show what it could do. On October 14, 1947, Major Charles “Chuck” Yeager sat in the cockpit of the orange-painted X-1 air­plane, which he had named Glamorous Glennis for his wife. He had to be helped into his seat because he had two broken ribs from a horse-riding acci­dent. A B-29 lumbered down the run­way, with the X-1 locked to its belly, and slowly climbed to 25,000 feet (7,620 meters). Then the signal came— release! For a moment, the airplane appeared to drop like a stone. Major Yeager then switched on the rocket engine to burn, and the X-1 took off.

That day, the X-1 reached a speed of 679 miles per hour (1,093 kilometers per hour). At 42,000 feet (12,802 meters), this speed is equal to Mach 1.05, or just above the speed of sound. Yeager had become the first person to fly at supersonic speed in level flight.

A few days later, the X-1 rocketed to a height of 70,119 feet (21,372 meters), setting a new world altitude record. The X-1 flew seventy-eight missions, reaching a top speed of 957 miles an hour (1,540 kilometers per hour) in March 1948.

After the X-1

Chuck Yeager went on to test the X-1’s successor, the X-1 A. Flying the new rocket plane, he set a world speed record of 1,650 miles per hour (2,655 kilometers per hour) or Mach 2.4, on December 12, 1953.

Two later and more advanced models of the X-1 (the X-1B and X1-E) were used to study specific areas of high­speed flight, including thermal (or heat) effects and different wing designs, adding to the data about supersonic per­formance. The only casualty of the test program was the X-1D. The aircraft was destroyed in 1951 after it had to be jet­tisoned from its B-50 “mother plane” following an explosion.

The Bell X-1 was followed by air­planes that flew faster and higher still, such as the Douglas Skyrocket. The Skyrocket was the first to fly at Mach 2 (1953). The Bell X-2 broke the Mach 3 barrier in 1956. The North American X – 15 was the ultimate in rocket planes. Like its predecessor the X-1, the X-15 was also launched from beneath a bomber. It broke record after record, and in 1967 flew at Mach 6.7—4,534 miles per hour (7,295 kilometers per hour), flying so high it was almost in space.

SEE ALSO:

• Air and Atmosphere • Aircraft,

Experimental • Aircraft Design

• Altitude • Engine • Jet and Jet

Power • Supersonic Flight

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Date of birth: July 1, 1872.

Place of birth: Cambrai, France.

Died: August 2, 1936.

Major contributions: First person to fly across the English Channel; first person to fly with two passengers; developer of the system for controlling direction and elevation; director of a company that produced an important fighter plane of World War I.

Awards: Member of France’s Legion d’Honneur.

hen he was a young man, Louis Bleriot made a small fortune by manufacturing headlights for automobiles. He then became fascinated by aviation.

Early Attempts

Beginning in 1900, Bleriot tried various aircraft designs, including one with bat­like wings flapped by the engine, several biplanes (with two sets of wings), a monoplane (single wing), and a design that had one wing set behind another. All of these test planes crashed.

Bleriot returned to a single-wing design and developed an airplane-the Bleriot Vl-with a modern appearance. The engine was in front, with large wheels underneath. The rudder and ele­vator were in the rear, and a smaller wheel was mounted below the tail. The plane’s body was completely covered, and there were no support wires visible on the exterior.

Bleriot flew the plane 240 feet (73 meters) before it crashed, and he decid­ed to perfect the design. As he tinkered, he developed a joystick to adjust eleva­tion and a bar under his feet to change direction. Similar systems are still used in aircraft today.

By 1909, Bleriot’s fortune was nearly gone, but he did not give up. Spurring him on was a large cash prize offered by the Daily Mail, a British newspaper, to the first person to fly across the English Channel (the stretch of water between England and France).

When the space race between the V United States and the Soviet Union began in 1957, the first U. S. rockets were launched from Cape Canaveral. Titan and Delta rockets are still launched from the same launch pads today.

In the early 1960s, the first U. S. manned spaceflights were launched from Cape Canaveral for the newly founded National Aeronautics and Space Administration (NASA). The first two manned suborbital Mercury flights were launched from Launch Complex 5 in 1961. Four manned orbital Mercury flights took off from Launch Complex 14 in 1961 and 1963. All ten manned Gemini missions began from Launch Complex 19. The Gemini missions took place in 1965 and 1966.

Manned launches switched to the nearby Kennedy Space Center when the Apollo missions began in 1967, but the Kennedy Space Center and the Cape Canaveral Air Force Station continue to work closely together. Unmanned launches, including those of NASA

space probes-the Mars Pathfinder, for example-take place at the Air Force Station. The station also fulfills its role as one of the two main U. S. military spaceports. (The other is Vandenberg Air Force Base in southern California.)

The economies of Cape Canaveral, neighboring Merritt Island (home to the Kennedy Space Center), and the sur­rounding towns now depend on the space industry and the millions of tourists it attracts. The Cape Canaveral area has become known as Florida’s “Space Coast.”

SEE ALSO:

• Kennedy Space Center • NASA

• Rocket • Space Probe

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NASA communicates with its deep-space probes in a different way, by using the Deep Space Network. When radio signals from distant space probes arrive at Earth, they are very weak. Huge radio dishes are needed to

collect the signals. The dishes are too big to be launched into space, but a big dish on Earth cannot stay in constant contact with a space probe. For half of every day, the dish would be on the wrong side of Earth.

NASA uses three huge dishes to stay in touch with space probes all over the Solar System. The dishes, each 230 feet (70 meters) across, are spaced equally around the world. One dish is located at Goldstone, California. The second is near Madrid, Spain, and the third is near Canberra, Australia. At busy times, a 210-feet (64-meter) dish at Parkes, Australia, is also used.

The dishes must be big because the radio signals they receive are very weak.

If the signals from the farthest space probes were saved up for one billion years, there still would not be enough energy to power a light bulb. These dish­es, however, can lock onto the tiny radio signal from a space probe 10 billion miles (16 billion kilometers) from Earth!

SEE ALSO:

• Air Traffic Control • Avionics

• Satellite • Sound Wave

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Concorde

Type: Commercial transport, supersonic airliner.

Manufacturer: Aerospatiale (France) and British Aerospace.

First flight: March 2, 1969.

Primary users: Air France,

British Airways.

oncorde was a supersonic

transport (SST) that flew at Mach

2, which is twice the speed of sound. Tech­nically, it was a remark­able airplane, and its

passengers were thrilled by the experience of

speeding through the strato­sphere faster than a bullet.

Concorde began passenger services in 1976 and was retired in 2003.

In the 1950s, engineers began drawing up plans for a new generation of high-speed

О As Concorde prepares to land in 2003, the world’s only supersonic passenger service was coming to an end. When Concorde landed, the aircraft pointed upward, but its droop – snoop nose tipped downward to help the pilot’s view.

airliners. Development costs were so high that the French aerospace company Aerospatiale joined forces with British Aerospace to build a supersonic airliner. Two Concorde prototypes were built, one at Toulouse, in France, and the other at Filton, near Bristol in England. Concorde 001 first flew on March 2, 1969, in France. Concorde 002s first flight was on April 9, 1969, at Bristol.

Concorde was an instantly recogniz­able delta-wing airplane. It was powered by four Rolls-Royce/SNECMA Olympus turbojet engines, each producing 38,050 pounds (169 kilonewtons) of thrust. The plane cruised at just over Mach 2 at 51,000 feet (15,545 meters), equivalent to 1,354 miles per hour (2,179 kilometers per hour). This made it twice as fast as the first – generation jet airliners, such as the 707, that were in service when Concorde took to the skies. Concorde’s normal range was 3,870 miles (6,227 kilometers).

Much of the fuel was stored in the wings. The fuel acted as a coolant, helping to reduce the wing temperature when the aircraft was flying supersonic. When coming in to land, Concorde had a steep angle of attack, meaning that it pointed upward. To give the pilot a better view of the runway, Concorde had a “droop snoop,” a nose that could be lowered.

The passenger cabin was slimmer than the cabin of its wide-bodied trans­atlantic rival, the Boeing 747, which also flew for the first time in 1969. While the 747 could carry up to four times as many passengers, Concorde was expected to attract people willing to pay for a faster flight—New York to London in about 3 hours. Maximum seating in Concorde allowed for 144 passengers.

Air France and British Airways began scheduled passenger services simultane­ously on January 21, 1976. There were objections from U. S. environmental groups, however, which complained about Concorde’s noise and its “sonic boom.” They argued that Concorde would damage buildings, frighten livestock, and disturb sleepers at night. Environmental fears halted plans to fly Concorde supersonic across the United States, and without U. S. airline sales, Concorde’s commercial prospects were damaged. By the 1970s, air travel was a mass-market business. Airlines were eager to fill the 300 to 400 seats of jumbo jets and less eager to buy an air­plane that provided expensive, high­speed travel.

CONCORDSKI

No U. S. manufacturer ever built a supersonic transport. The Soviet Union, however, produced the Tupolev Tu-144, the first SST ever to fly (on December 31, 1968). Nicknamed ”Concordski” because of its close resemblance to Concorde with its drooping nose, the Tu-144 cruised at 1,550 miles per hour (2,500 kilome­ters per hour). Passenger services lasted only from November 1977 to June 1978, when the aircraft was withdrawn after a crash.

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On July 25, 2000, an Air France Concorde crashed after takeoff from Charles de Gaulle Airport in Paris. All 100 passengers, nine crew, and four peo­ple on the ground were killed. Accident investigators found that a tire had burst after hitting an object on the runway. The debris had fractured a fuel tank, causing a fire in one engine. In April 2003, the two airlines announced that they were retiring Concorde. In 2003, with several Concorde farewell flights, the first era of supersonic passenger transport came to an end.

SEE ALSO:

• Aircraft, Commercial • Aircraft Design • Supersonic Flight

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Charles Lindbergh made his famous solo flight across the Atlantic Ocean in 1927. That feat stirred heiress Amy Phipps Guest to strive to be the first woman to make that flight. She bought an air­plane, but her family would not permit her to make the trip. Determined to see a woman achieve her goal, Guest asked publisher George Palmer Putnam to help her find someone who was willing and able to do so.

Earhart was recommended to Put­nam, who took a liking to her. (Later, the two were married.) Earhart later recalled her feelings when offered the chance to take part: “How could I refuse such a shining adventure!”

The flight took place on June 4, 1928. Earhart did none of the flying— two male pilots handled that chore. But the mere fact of her having been the first woman to cross the ocean gained her fame. She was heralded as “Lady Lindy” and treated to parades and banquets.

Earhart was determined to use her fame to promote flying for women. In 1929 she helped lead the effort to found an organization, the Ninety-Nines, which aimed to bring more women into aviation. The group’s name came from

the fact that it included ninety-nine of the 117 American women who held pilot’s licenses at the time.