Supersonic Travel—Is It Here to Stay?
A NEW age in aviation began on January 21, 1976. Two sleek, beak-nosed planes, one in London, the other in Paris, raced down their runways for near-simultaneous takeoffs. Commercial supersonic air travel in the Western world was inaugurated!
The plane taking off from Paris was on its maiden flight to Rio de Janeiro, Brazil, by way of Dakar, Senegal. As the aerial speedometer (called a Machmeter), within view of passengers up front, reached the speed of sound, one of them reported: “There were gasps and cheers. Then came an announcement from the cockpit: ‘Ladies and gentlemen, you have just become the first 100 passengers in the history of the world to pass the speed of sound in a scheduled flight.’”
Actually, the Soviet Union began supersonic service first—with its TU-144, in December 1975—but it was for mail and cargo only. Not until November 1977 did the Soviets commence scheduled supersonic passenger service from Moscow to Alma-Ata in central Asia.
The plane that inaugurated supersonic passenger service is the Concorde, produced jointly by Britain and France. Sixteen Concordes either have been built or are under construction, and nine are now in service.
In their first year the Concordes had 45,000 fare-paying passengers. There would have been many more if it had not been for the great opposition to these planes. Regular flights into the Washington, D.C., area were not permitted until May 24, 1976. And it was another year and a half before scheduled flights were allowed into New York city late in 1977.
Why is there opposition to supersonic passenger jets? Is the continuance of their service really in jeopardy? What are the advantages of supersonic travel?
Faster than Sound
The obvious advantage is speed, getting places faster. Generally, flight in a subsonic jet from Paris to Washington, D.C., takes between seven and eight hours. However, a Concorde passenger observes: “Air France’s Concorde Flight 53 departed Charles de Gaulle Aeroport [Paris] at 8:00 P.M. and touched down at Dulles International Airport [near Washington, D.C.] at 5:55 P.M. . . . The trip had taken precisely 3 hours, 55 minutes.”
That’s right, passengers traveling westward on the Concorde actually reach their destinations at an earlier hour than when they departed. This is because the Concorde flies faster than the sun moves across the sky. Thus, one can leave Europe after watching a sunset and arrive in the United States during daylight and watch the sun set again that same day! Or one can leave Paris during the early morning of, say, January 22, and arrive in New York on the night of January 21.
The Concorde cruises at the approximate speed of a rifle bullet. Less time in flight reduces travel fatigue, and this is cited by passengers as a real advantage. Little passenger comfort is sacrificed; it is comparable to that experienced in other airliners. One traveler declared: “Once you’ve gone Concorde, you’ll never go any other way.”
Public preference has long been for an aircraft with a speed advantage. In the 1930’s the DC-3 made the Boeing 247 obsolete by cutting the flying time across the United States from 19 hours to 15. After World War II, passenger planes kept getting faster and faster. Then, in 1958, when passenger planes began to employ jet propulsion, flying times suddenly were reduced even more, and piston-engined planes became obsolete.
Jet passenger planes soon began approaching the speed of sound. And, in view of the military’s development of supersonic planes, it seemed only logical that civilians, too, should travel faster than sound.
The Sound Barrier
In warm air at sea level sound travels about 760 miles per hour (1,220 kilometers per hour), while at a height of about 37,000 feet (11,200 meters) the speed is only 660 miles (1,060 kilometers) per hour. Air has great elasticity, and when a plane is moving at slower speeds air molecules move fast enough to get out of the plane’s way. But when the speed of sound is reached this is no longer true.
A supersonic aircraft overtakes the moving air molecules and compresses layers of air in its flight. This produces great frictional forces that cause strong vibration and heating of the plane’s outside surface. As a result of the tremendous air resistance, many once thought that there was a so-called “sound barrier” that could not be broken.
However, improved design of aircraft reduced friction and eventually made it possible to surpass the speed of sound. This was first accomplished by a manned aircraft—a rocket plane—on October 14, 1947. But it was not until 1953 that the North American F-100 Super Sabre jet fighter became the first jet to fly faster than sound in level flight. By the late 1950’s, supersonic military planes had come into use. In tests during the early 1960’s, a DC-8 became the first passenger liner to break the sound “barrier.” By that time supersonic passenger planes were already on drawing boards.
Development
The Soviet Union, the United States, Britain and France were all interested in building such a plane. Due to the size of the undertaking, Britain and France signed an agreement on November 29, 1962, to coordinate their efforts. At the time it was anticipated that there would be a world market for up to 500 supersonic passenger planes. A British Aircraft Corporation sales manager was predicting sales of 225 Concordes by 1975.
In time, preproduction models of the Concorde were produced. The first one flew on March 2, 1969, and in 1970 supersonic speeds were first attained. But there were problems that kept running up production costs. At the same time, opposition to the whole idea of supersonic flight became very strong. Thus in the spring of 1971 the U.S. scrapped its plans for the project when, after spending nearly $1 billion, Congress cut off all further government funding.
The hoped-for sales of the Concorde did not materialize. The highest number of options to buy them was only 74. Then, on January 21, 1973, a major blow came when Pan American World Airways and Trans World Airlines canceled their options to buy 13 planes. Other carriers later also dropped options to buy. Thus, besides British Airways and Air France, which are the only airlines that have Concordes, only Red China and Iran National Airlines still have orders to buy them.
Another major blow fell in June 1973. It occurred during the Paris Air Show. The Soviets were demonstrating a preproduction TU-144 supersonic plane when it crashed and killed at least 13 persons. This worried those who still had options to buy Concordes; they wondered about its safety too. Also, the Soviet program was set back, so that the Soviets were eventually almost two years behind the British and French in initiating supersonic passenger service.
On December 6, 1973, the first production Concorde began flying. Flight tests took it all over the world. It visited over 40 countries and landed at 70 international airports. After over 5,000 flying hours the plane was given a certificate of airworthiness and, as already noted, began regular air service in January 1976.
Travel by Concorde means that a person is less than 12 hours away from practically any place on earth. It often cuts in half the time it takes other planes to get to places. Why, then, is there such strong opposition to its operation?
Possible Atmospheric Damage
At a height of about six miles (10 kilometers) over the poles and 10 miles (16 kilometers) over the equator the stratosphere begins. From there the stratosphere extends up to about 30 miles (50 kilometers). Its lower layer remains cold and clear, and this is where the supersonics fly. Scientists, however, see the possibility of the planes’ polluting this atmosphere, perhaps disastrously affecting life on earth.
Some have said that nitric oxides emitted by the jet exhausts could degrade the stratosphere’s ozone. The ozone provides a protective umbrella to prevent excessive ultraviolet radiation from the sun from reaching the earth. According to some estimates, only a small decrease in the ozone could result in a big increase in the amount of ultraviolet radiation reaching earth. With what consequences?
Food crops, forest ecology, insect life, plankton in the oceans and, of course, human life could be adversely affected. In fact, some have feared that even a limited six flights a day of the Concorde could lead to an increase of skin cancer. Of course, this is only a speculation, but certainly it is one for consideration.
A U.S. senator, however, notes that military planes have made more than a million supersonic flights without any apparent damage to the ozone layer. If supersonic flights are really a serious potential danger, why not ban military supersonics? The following letter to the New York Times makes a worthwhile point about this:
“It is with some amazement that I realize the Senators and Representatives who voted to ban the SST [Supersonic Transport] because of its effect on the ozone layer are the same people, by and large, who have voted to approve funds for the B-1 bomber—$21 billion for the production of 244 supersonic bombers. The media also has kept a low profile on the fact that for more than a decade there have been regular and very numerous supersonic military flights . . . It seems very hypocritical to me to vote to ban one without banning the other.”
However, the opposition to the Concorde—which has taken the form of demonstrations that clogged roads leading to New York’s Kennedy Airport for hours—is based primarily on another objection—Noise.
Noise Pollution
Anyone who has spent time close to a modern airport can surely sympathize with persons who have to live close to one. The whining and screaming of modern jets can be deafening. And the Concorde has the reputation of being the loudest of them all, although its noise is somewhat different.
“It’s a lower, deeper sound,” observes Dexter Davis, manager of Dulles Airport near Washington, D.C. “I find it much less irritating than a whining sound.” A resident near London’s Heathrow Airport says: “I know when it’s a Concorde. The noise is totally different. The windows shake in our porch from vibration. And when I am at my friend’s house in Hatton Cross I have to cover my ears with my hands.”
There are differences of opinion regarding the objectionableness of the supersonics as compared with other jets. The Wall Street Journal commented editorially: “Those of us who have heard the Concorde land and take off can distinguish very little difference between its noisiness and the noisiness of a 707.”
However, the Concorde often registers more noise than other jets. Yet the New York Post of November 4, 1977, reports: “The Federal Aviation Administration said yesterday that the average noise level at each of seven locations where it took readings during test flights [of the Concorde] was within acceptable limits.”
Surely, though, this is little comfort to persons living near airports. Already they suffer with noise that they, and probably anyone else living where they do, would consider unacceptable. And now the prospects of an aircraft, even noisier, landing and taking off is understandably a reason for them to wish they could move away.
Sonic Boom
Opposers of the Concorde also point to the sonic boom it produces. As military supersonics have demonstrated, the “booms” can be strong enough to shatter glass. “They sound very much like exploding bombs,” writes one person, “causing the curtains of my bungalow to blow inward and parts of the building to creak.”
Sonic boom is caused as an aircraft traveling faster than sound compresses the air. This suddenly compressed air forms shock waves that can be heard and felt miles away. It is similar to thunder; in fact, the noise caused by a lightning stroke is also a sonic boom.
A common misconception about an aircraft’s sonic boom is that it is produced only at the moment that the plane passes the “sound barrier.” Actually, as the plane travels along at supersonic speeds, the boom is continuous. It can be heard on the ground 10 miles (16 kilometers) below by persons who happen to be living in a wide area along the flight path of the plane.
Obviously sonic boom can be very objectionable. So Concordes fly principally over oceans where the shock waves do not disturb anyone or cause damage. When the planes near populated areas they slow down to below the speed of sound in order to avoid producing sonic boom. Thus the Concorde is limited principally to overseas routes. Because of this limitation, other jets can provide service about as fast over populated land areas, and for a much cheaper fare.
Here to Stay?
This is a meaningful question, and principally because of this very matter of money. Over the years the French and British governments have spent over $3 billion to develop the Concorde. One now costs about $80 million, or almost twice as much as a jumbo jet. Further, for the number of passengers carried, it also is more costly to operate a Concorde than other jets.
A Concorde is only a third the size of the jumbo 747 jet, and carries fewer than a third the passengers. So the cost is about 20 percent more to fly on the Concorde than to fly first class on other jets. A round-trip flight between New York and London is $1,586, compared to first-class round-trip seats on other jets for $1,312, and about $700 for tourist-class fare.
The question is: Will persons be willing to pay the extra money to get places faster? So far it has not looked good. Supersonic flights have not made money. In fact, in 1976, the two airlines flying Concordes lost a combined total of $54 million!
A particular problem is that presently few routes are serviced by the Concorde. British Airways has flights to Washington, D.C., to Singapore and to Bahrain, on the Persian Gulf. And Air France has been flying to Washington, D.C.; Caracas, Venezuela; and Rio de Janeiro, Brazil. Only since November 1977 have the two airlines been able to begin flights between their national capitals and New York city.
It is obvious that to remain operational the Concorde needs regular routes to important business and population centers such as New York. But a major shortcoming is Concorde’s lack of range. With a capacity load of about 100 passengers, it can barely carry fuel sufficient to make it from Paris to Washington, D.C.
Thus the problems of the Concorde are serious. It probably means that no more than the 16 Concordes will be built. Yet, because of public preference for speed advantage, it seems likely that supersonic aircraft will continue to fly. In fact, in November 1977 the U.S. National Aeronautics and Space Administration awarded Lockheed-California Company a new $270,000 federal contract to study the design of a yet more advanced type of supersonic aircraft.
The proposed new plane would carry 200 passengers at a cruise speed of 4,000 miles (6,440 kilometers) per hour. Its range would be 6,000 miles (9,660 kilometers), and it would fly at about 120,000 feet (36,500 meters), at which altitude the sonic boom would not be objectionable by the time it reaches earth. It will be interesting to follow further developments in supersonic travel.
[Picture on page 17]
The “sonic boom” is heard along the flight path wherever the shock wave intersects with the ground