Supersonic passenger plane

The invention: 



The first commercial airliner that flies passengers at

speeds in excess of the speed of sound.





The people behind the invention:



Sir Archibald Russell (1904- ), a designer with the British

Aircraft Corporation

Pierre Satre (1909- ), technical director at Sud-Aviation

Julian Amery (1919- ), British minister of aviation, 1962-1964

Geoffroy de Cource (1912- ), French minister of aviation,

1962

William T. Coleman, Jr. (1920- ), U.S. secretary of

transportation, 1975-1977









Birth of Supersonic Transportations



On January 21, 1976, the Anglo-French Concorde became the

world’s first supersonic airliner to carry passengers on scheduled

commercial flights. British Airways flew a Concorde from London’s

Heathrow Airport to the Persian Gulf emirate of Bahrain in

three hours and thirty-eight minutes. At about the same time, Air

France flew a Concorde from Paris’s Charles de Gaulle Airport to

Rio de Janeiro, Brazil, in seven hours and twenty-five minutes.

The Concordes’ cruising speeds were about twice the speed of

sound, or 1,350 miles per hour. On May 24, 1976, the United States

and Europe became linked for the first time with commercial supersonic

air transportation. British Airways inaugurated flights

between Dulles International Airport in Washington, D.C., and

Heathrow Airport. Likewise, Air France inaugurated flights between

Dulles International Airport and Charles de Gaulle Airport.

The London-Washington, D.C., flight was flown in an unprecedented

time of three hours and forty minutes. The Paris-

Washington, D.C., flight was flown in a time of three hours and

fifty-five minutes.





The Decision to Build the SST



Events leading to the development and production of the Anglo-

French Concorde went back almost twenty years and included approximately

$3 billion in investment costs. Issues surrounding the

development and final production of the supersonic transport (SST)

were extremely complex and at times highly emotional. The concept

of developing an SST brought with it environmental concerns

and questions, safety issues both in the air and on the ground, political

intrigue of international proportions, and enormous economic

problems from costs of operations, research, and development.

In England, the decision to begin the SST project was made in October,

1956. Under the promotion of Morien Morgan with the Royal

Aircraft Establishment in Farnborough, England, it was decided at

the Aviation Ministry headquarters in London to begin development

of a supersonic aircraft. This decision was based on the intense competition

from the American Boeing 707 and Douglas DC-8 subsonic

jets going into commercial service. There was little point in developing

another subsonic plane; the alternative was to go above the speed

of sound. In November, 1956, at Farnborough, the first meeting of the

Supersonic Transport Aircraft Committee, known as STAC, was held.

Members of the STAC proposed that development costs would be

in the range of $165 million to $260 million, depending on the range,

speed, and payload of the chosen SST. The committee also projected

that by 1970, there would be a world market for at least 150 to 500 supersonic

planes. Estimates were that the supersonic plane would recover

its entire research and development cost through thirty sales.

The British, in order to continue development of an SST, needed a European

partner as a way of sharing the costs and preempting objections

to proposed funding by England’s Treasury.

In 1960, the British government gave the newly organized British

Aircraft Corporation (BAC) $1 million for an SST feasibility study.

Sir Archibald Russell, BAC’s chief supersonic designer, visited Pierre

Satre, the technical director at the French firm of Sud-Aviation.

Satre’s suggestion was to evolve an SST from Sud-Aviation’s highly

successful subsonic Caravelle transport. By September, 1962, an

agreement was reached by Sud and BAC design teams on a new

SST, the Super Caravelle.

There was a bitter battle over the choice of engines with two British

engine firms, Bristol-Siddeley and Rolls-Royce, as contenders.

Sir Arnold Hall, the managing director of Bristol-Siddeley, in collaboration

with the French aero-engine company SNECMA, was eventually

awarded the contract for the engines. The engine chosen was

a “civilianized” version of the Olympus, which Bristol had been developing

for the multirole TRS-2 combat plane.



The Concorde Consortium



On November 29, 1962, the Concorde Consortium was created

by an agreement between England and the French Republic, signed

by Ministers of Aviation Julian Amery and Geoffroy de Cource

(1912- ). The first Concorde, Model 001, rolled out from Sud-

Aviation’s St. Martin-du-Touch assembly plant on December 11,

1968. The second, Model 002, was completed at the British Aircraft

Corporation a few months later. Eight years later, on January 21,

1976, the Concorde became the world’s first supersonic airliner to

carry passengers on scheduled commercial flights.

Development of the SST did not come easily for the Anglo-

French consortium. The nature of supersonic flight created numerous

problems and uncertainties not present for subsonic flight. The

SST traveled faster than the speed of sound. Sound travels at 760

miles per hour at sea level at a temperature of 59 degrees Fahrenheit.

This speed drops to about 660 miles per hour at sixty-five thousand

feet, cruising altitude for the SST, where the air temperature

drops to 70 degrees below zero.

The Concorde was designed to fly at a maximum of 1,450 miles

per hour. The European designers could use an aluminum alloy

construction and stay below the critical skin-friction temperatures

that required other airframe alloys, such as titanium. The Concorde

was designed with a slender curved wing surface. The design incorporated

widely separated engine nacelles, each housing two Olympus

593 jet engines. The Concorde was also designed with a “droop

snoot,” providing three positions: the supersonic configuration, a

heat-visor retracted position for subsonic flight, and a nose-lowered

position for landing patterns.





Impact



Early SST designers were faced with questions such as the intensity

and ionization effect of cosmic rays at flight altitudes of sixty to

seventy thousand feet. The “cascade effect” concerned the intensification

of cosmic radiation when particles from outer space struck a

metallic cover. Scientists looked for ways to shield passengers from

this hazard inside the aluminum or titanium shell of an SST flying

high above the protective blanket of the troposphere. Experts questioned

whether the risk of being struck by meteorites was any

greater for the SST than for subsonic jets and looked for evidence on

wind shear of jet streams in the stratosphere.

Other questions concerned the strength and frequency of clear air

turbulence above forty-five thousand feet, whether the higher ozone

content of the air at SST cruise altitude would affect the materials of

the aircraft, whether SST flights would upset or destroy the protective

nature of the earth’s ozone layer, the effect of aerodynamic heating

on material strength, and the tolerable strength of sonic booms

over populated areas. These and other questions consumed the designers

and researchers involved in developing the Concorde.

Through design research and flight tests, many of the questions

were resolved or realized to be less significant than anticipated. Several

issues did develop into environmental, economic, and international

issues. In late 1975, the British and French governments requested

permission to use the Concorde at New York’s John F.

Kennedy International Airport and at Dulles International Airport

for scheduled flights between the United States and Europe. In December,

1975, as a result of strong opposition from anti-Concorde

environmental groups, the U.S. House of Representatives approved

a six-month ban on SSTs coming into the United States so that the

impact of flights could be studied. Secretary of TransportationWilliam

T. Coleman, Jr., held hearings to prepare for a decision by February

5, 1976, as to whether to allow the Concorde into U.S. airspace.

The British and French, if denied landing rights, threatened

to take the United States to an international court, claiming that

treaties had been violated.

The treaties in question were the Chicago Convention and Bermuda

agreements of February 11, 1946, and March 27, 1946. These

treaties prohibited the United States from banning aircraft that both

France and Great Britain had certified to be safe. The Environmental

Defense Fund contended that the United States had the right to ban

SST aircraft on environmental grounds.

Under pressure from both sides, Coleman decided to allow limited

Concorde service at Dulles and John F. Kennedy airports for a

sixteen-month trial period. Service into John F. Kennedy Airport,

however, was delayed by a ban by the Port Authority of New York

and New Jersey until a pending suit was pursued by the airlines.

During the test period, detailed records were to be kept on the

Concorde’s noise levels, vibration, and engine emission levels. Other

provisions included that the plane would not fly at supersonic

speeds over the continental United States; that all flights could be

cancelled by the United States with four months notice, or immediately

if they proved harmful to the health and safety of Americans;

and that at the end of a year, four months of study would begin to

determine if the trial period should be extended.

The Concorde’s noise was one of the primary issues in determining

whether the plane should be allowed into U.S. airports. The Federal

Aviation Administration measured the effective perceived noise

in decibels. After three months of monitoring the Concorde’s departure

noise at 3.5 nautical miles was found to vary from 105 to 130

decibels. The Concorde’s approach noise at one nautical mile from

threshold varied from 115 to 130 decibels. These readings were approximately

equal to noise levels of other four-engine jets, such as

the Boeing 747, on landing but were twice as loud on takeoff.





The Economics of Operation



Another issue of significance was the economics of Concorde’s

operation and its tremendous investment costs. In 1956, early predictions

of Great Britain’s STAC were for a world market of 150 to

500 supersonic planes. In November, 1976, Great Britain’s Gerald

Kaufman and France’s Marcel Cavaille said that production of the

Concorde would not continue beyond the sixteen vehicles then contracted

for with BAC and Sud-Aviation. There was no demand by

U.S. airline corporations for the plane. Given that the planes could

not fly at supersonic speeds over populated areas because of the

sonic boom phenomenon, markets for the SST had to be separated

by at least three thousand miles, with flight paths over mostly water

or desert. Studies indicated that there were only twelve to fifteen

routes in the world for which the Concorde was suitable. The planes

were expensive, at a price of approximately $74 million each and

had a limited seating capacity of one hundred passengers. The

plane’s range was about four thousand miles.

These statistics compared to a Boeing 747 with a cost of $35 million,

seating capacity of 360, and a range of six thousand miles. In

addition, the International Air Transport Association negotiated

that the fares for the Concorde flights should be equivalent to current

first-class fares plus 20 percent. The marketing promotion for

the Anglo-French Concorde was thus limited to the elite business

traveler who considered speed over cost of transportation. Given

these factors, the recovery of research and development costs for

Great Britain and France would never occur.



See also : Airplane; Bullet train; Dirigible; Rocket; Stealth aircraft;

                 Supersonic transport











Further Reading