Monday, May 2, 2022

The De Havilland Comet—Age of Commercial Jets Stumbles Out of the Gate

BOAC passengers celebrate as they board the Comet's first Transatlantic service in front of a large crowd of dignitaries, DeHavilland and BOAC executives, and the press.

The modern era of passenger jet travel was inaugurated with great celebration on May 2, 1952 by British Overseas Airway Corporation (BOAC) on its long London to Johannesburg route.  They were flying the De Havilland DH 106 Comet

It was an aerodynamically sleek aircraft with four powerful turbojet engines buried in the root of its swept back wings near the commodious fuselage.  It carried 36 passengers with plenty of leg room and reclining seats for the long flights arranged four abreast with a center aisle.  The lucky passenger could view the world far below them through large, square windows.

Soaring above the clouds and foul weather that conventional propeller driven airliners had to fly through, the flight was remarkably smooth.  And quiet.  Despite early fears that the jet engines would be loud, their configuration actually made them quieter than the four heavy engines on most long distance air liners—and with less vibration for the passengers.

The United Kingdom was fairly bursting with pride at the achievement.  They had beaten the Americans whose major aircraft companies were either tied up with military production or complacent with the newest generation of prop planes—the Douglas DC-6 and Lockheed’s mammoth Super Constellation—and perhaps even more satisfactorily the French who were dithering with their own plans.

The country was ready for some good news in those days.  The post-World War II years had been very tough.  Much of its industrial production was damaged, outmoded, or so long converted to military usage that transition back to civilian production was hard.  The second consecutive generation of young men had been decimated as casualties of warLabor discontent was rife. 

Pridefully, the country had declined to participate in the largess of the American Marshal Plan which was rebuilding much of shattered Europe, including former foes Germany and Italy.  West Germany was quickly resuming its place as a center of heavy industry and advanced engineering.  Italy was rising on the strength of extraordinary forward thinking design that was pleasing consumers around the world. Britain slogged along.

Worse, its far flung Empire was unraveling.  India, the crown jewel, was already gone.  The protectorates in the Middle East, and their vast oil reserves lost and dominance over Egypt was swept away by Arab Nationalism. Unrest and simmering revolt stewed in Africa.  Winston Churchill had returned to 10 Downing Street vowing, “I did not become Her Majesty’s First Minister to preside over the dismemberment of the British Empire.”  But, of course, he did.

So, the success of the Comet was looked on as a sign the Britain was resuming her place at the head of nations in industrial and commercial development.

Design plans for the Comet quickly evolved from a small twin-tail mail packet during the war to larger sizes including a radical delta wing versions without a tail horizontal tail stabilizer in 1946 to the final production design in 1947.

The Brits got a head start of jet production because even as the war was raging.  The Brabazon Committee was charged by the Cabinet to plan for the nations post-war civilian aircraft needs. By 1944 the Committee had placed the highest priority on the development of a high speed “mail packet” capable of carrying at least a few passengers and crossing the Atlantic nonstop. Over the next several years conceptual drawings were made that saw the plane grow from a small twin tail boom craft to a much larger, radical design with delta wings and no horizontal tail stabilizer.  A prototype of the latter was ordered for testing in 1946 but proved unstable.  Some engineers wanted to continue to pursue that path, but available jet engines were not deemed powerful enough.

Instead, the committee and De Havilland settled onto a more conventional swept wing design originally intending it for 24 passengers.  As prototypes of that plane began to be tested in 1949, it was decided that improved turbojet engines could accommodate a longer body.

The first production model of the Comet DH-106 took to the air in 1952,

The resulting DH-106 model went into commercial production in 1951 with pre-orders from BOAC and British South American Airways with several other prospective customers in the wings if commercial service proved profitable and successful.  By the end of the year orders were pouring in from France other European countries, and Canada.  At least three U.S. carriers pre-ordered planned second or third generation Comets with expanded passenger capacity.

But thing soon began to go sour.  Within the first year there were three accidents resulting in the loss of aircraft.  Two of them were failures on takeoff resulting in no loss of life, but the third, a new Canadian Pacific Airlines Comet 1A, failed become airborne while attempting takeoff from Karachi, Pakistan, on a delivery flight to Australia on March 3, 1953. The aircraft plunged into a dry drainage canal and collided with an embankment, killing all five crew and six passengers on board.  The Canadian Airline immediately canceled its order for more planes, as did other carriers in a crisis of confidence.

Investigators piecing together of the wreckage of the Karachi crash.

The British government and De Havilland launched a desperate investigation.  After running down several false leads, it was discovered that the then little understood metal fatigue had caused catastrophic hull failure.  Specifically stresses at the corners of the fuselage’s signature square windows caused cracks to develop.

Stress cracks around the corners of the Comet's large square windows resulting from metal fatigue caused the failure of the aircraft.

The discovery was so sensational in Britain that No Highway in the Sky, a popular novel and a film starring James Stewart, Marlene Dietrich, and Glynis Johns was based on it.  The pleas of the company kept the plane in the movie from being a jet.

By 1953 the redesigned Comet 2 with round portal windows and other improvements was introduced.  It severed without the same troubles and got orders.  Two more basic versions were introduced culminating in the Comet 4 in 1959 capable of carrying 99 passengers.  That version remained in commercial service until 1997 and military reconnaissance versions were flown by the British up to 2011.

But the Comet, whatever its virtues and they were many, never really recovered from the stumble out of the starting gate.  It introduction spurred American competitors into high gear in developing their own planes.

The Boing 707, which most Americans will swear was the first jetliner, went into service with TWA and Pan AM in October 1958 followed by the Douglas DC-8 a year later in service with United and Delta.  Together they and their successor aircraft would dominate Western long range civil aviation for two generations.

One possible niche for the smaller Comet 3 to be adapted as a short and medium range jet liner was cut off when French Sud Aviation put their revolutionary Caravelle with its rear mounted engines into production in 1959 with first sales to Scandinavian Airlines.  Soon they did what De Havilland could never accomplish—sell planes to an American carrier when United Airlines ordered 200 of them.

A model kit for a DeHavilland Comet like I assembled as a pre-teen in Cheyenne.

You might wonder about my interest in an aircraft barely acknowledged on this side of the puddle.  It might be because it was the first of many airplane models I ever built as a boy in Cheyenne who used to watch United DC-8s and Caravells practice take-off and landings on the long runway of the airport which ran just behind my house. 


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