Tag Archives: BOAC

19 May 1959

Boeing 707-436 Intercontinental N31241 (Associated Press)

19 May 1959: The first Boeing 707-436 Intercontinental, FAA registration N31241, made a 1 hour, 11 minute first flight from Renton to Boeing Field, Seattle, Washington.  The -436 was a stretched version of the original 707-120, but with Rolls-Royce Conway 508 bypass turbojet engines (now called turbofans) in place of the standard Pratt & Whitney JT3C-6 turbojet engines.

The fuselage and wings of the Intercontinental were lengthened, allowing an increased load and greater fuel capacity. It could carry 189 passengers and had a range 1,600 miles further than the -120. Transoceanic flights without an intermediate fuel stop were possible.

This airplane was the first of 15 which had been ordered by British Overseas Airways Corporation in 1956. It was re-registered G-APFB and delivered to BOAC 9 May 1960.

Boeing 707 Intercontinental “hero shot” from Boeing website. (Boeing)

Initially, British aviation authorities refused to certify the -436 because of low-speed handling concerns. Boeing increased the height of the vertical fin 40 inches and added a ventral fin. These modifications became standard on all future 707s and were retro-fitted to those already manufactured.

G-APFB served BOAC until 1974, and then with other airlines. It was sold to Boeing Commercial Airplane Company in 1976. The forward fuselage and cabin was shipped to Renton for use in Boeing’s E-3A Sentry program. The remainder of the airliner was scrapped in 1978.

The Boeing 707-420 series airliners were 152 feet, 11 inches (46.609 meters) long, with a wingspan of 142 feet, 5 inches (43.409 meters) and overall height 42 feet, 2 inches (12.852 meters) at its operating empty weight. The leading edges of the wings and tail surfaces are swept 35°. The fuselage has a maximum diameter of 12 feet, 8.0 inches (3.759 meters). The 707 International has a typical empty weight of 142,600 pounds (64,682 kilograms), and a maximum takeoff weight (MTOW) of 312,000 pounds (141,700 kilograms). The usable fuel capacity is 23,820 gallons (90,169 liters).

All 707-series aircraft are powered by four jet engines installed in nacelles below and forward of the wings on pylons. The -420 Internationals were powered by Rolls-Royce Conway Mk. 508 engines. The Rolls-Royce Conway (R.Co.12) is a two-spool, axial-flow, low-bypass turbofan engine. The engine has a 7-stage low- and 9-stage high-pressure compressor section, 12 interconnected combustion liners, with a single-stage high- and 2-stage low-pressure turbine. The Mk. 508 has a Maximum Continuous Power rating of 14,625 pounds of thrust (65.055 Kilonewtons), and 17,500 pounds of thrust (77.844 Kilonewtons) at 9,990 r.p.m., for Takeoff. The engine is 3 feet, 6.0 inches (1.067 meters) in diameter, 11 feet, 4.0 inches (3.454 meters) long, and weighs 4,542 pounds (2,060 kilograms).

The -420 series had a maximum cruise speed of 593 miles per hour 954 kilometers per hour) at 30,000 feet (9,144 meters)—0.87 Mach; and economical cruise speed of 550 miles per hour (885 kilometers per hour) at 35,000 feet (10668 meters).

Boeing built 1,010 Model 707 airplanes between 1957 and 1979. Of these, 37 were the 707-420 Intercontinental variant.

A British Overseas Airways Corporation Boeing 707 Intercontinental airliner, similar in appearance to G-APFB. (Travell Update)

© 2018, Bryan R. Swopes

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8 April 1968

Barbara Jane Harrison, GC
Miss Barbara Jane Harrison, British Overseas Airways Corporation
This photograph shows Speedbird 712 over Thorpe, Surrey. The Number two Engine is circled at the lower right.

8 April 1968: British Overseas Airways Corporation Flight 712, call sign Speedbird 712, a Boeing 707-465 Intercontinental registered G-ARWE, departed London Heathrow for Sydney, Australia, with 116 passengers and 11 crew. Approximately 20 seconds after takeoff, there was a loud bang and severe shudder as the Number Two jet engine failed catastrophically. The flight crew started through emergency procedures while calling MAYDAY and turning back toward the airport. The failed engine fell off the left wing which then caught fire as fuel continued to flow. Three minutes, thirty-two seconds after takeoff, Speedbird 712 touched down on Runway 05 and rapidly came to a stop. Fuel continued to burn, and the airliner’s cabin crew began evacuating passengers.

Stewardess Barbara Jane Harrison was among the crew members who helped passengers escape from the burning Boeing 707. The exit slide had not deployed correctly and Miss Harrison was encouraging passengers to jump to the runway surface, and in some cases, even pushed them out. She was seen standing in a doorway as the flames and smoke spread, and people below, including the airplane’s captain, Cliff Taylor, shouted at her to jump. Instead, she turned away and went back inside, presumably to help a disabled passenger in a wheelchair. She gave her life to help others. Later, the bodies of Miss Harrison and the disabled passenger were found together in the burned out wreck. Four other passengers also died.

For her gallantry in saving the lives of others at the cost of her own, Queen Elizabeth II awarded the George Cross, for “acts of the greatest heroism or of the most conspicuous courage in circumstances of extreme danger.”

Barbara Jane Harrison was 22 years old.

CENTRAL CHANCERY OF THE ORDERS OF KNIGHTHOOD

ST. JAMES’S PALACE, LONDON S.W.1

8th August 1969.

The QUEEN has been graciously pleased to make the undermentioned award.

GEORGE CROSS

Miss Barbara Jane HARRISON (deceased), Stewardess, British Overseas Airways Corporation.

     On April 8th 1968, soon after take-off from Heathrow Airport, No. 2 engine of B.O.A.C. Boeing 707 G-ARWE caught fire and subsequently fell from the aircraft, leaving a fierce fire burning at No. 2 engine position. About two and a half minutes later the aircraft made an emergency landing at the airport and the fire on the port wing intensified. Miss Harrison was one of the stewardesses in this aircraft and the duties assigned to her in an emergency were to help the steward at the aft station to open the appropriate rear door and inflate the escape chute and then to assist the passengers at the rear of the aircraft to leave in an orderly manner. When the aircraft landed Miss Harrison and the steward concerned opened the rear galley door and inflated the chute, which unfortunately became twisted on the way down so that the steward had to climb down it to straighten it before it could be used. Once out of the aircraft he was unable to return; hence Miss Harrison was left alone to the task of shepherding passengers to the rear door and helping them out of the aircraft. She encouraged some passengers to jump from the machine and pushed out others. With flames and explosions all around her and escape from the tail of the machine impossible she directed her passengers to another exit while she remained at her post. She was finally overcome while trying to save an elderly cripple who was seated in one of the last rows and whose body was found close to that of the stewardess. Miss Harrison was a very brave young lady who gave her life in her utter devotion to duty.

—Supplement to The London Gazette of Thursday, 7th August 1969, Friday, 8th August 1969, No. 44913, at Page 8211, Column 1.

BOAC Flight 712, a Boeing 707-465, G-ARWE, burning on the runway at Heathrow, 8 April 1968.
BOAC Flight 712, a Boeing 707-465, G-ARWE, burning on the runway at Heathrow, 8 April 1968.

Only four women have been awarded the George Cross: Violet Szabó, Odette Sansom, Noor Inayat Khahn, all three secret intelligence agents for England’s Special Operations Executive (S.O.E.) during World War II, and Barbara Jane Harrison.

Barbara Jane Harrison was born at Kingsdale Crescent, Bradford, Yorkshire, England, 14 May 1945. She was the second of two daughters of Alan Frederic Harrison, a police officer, and Lena Veronica Adlard Harrison. Her mother died when she was ten years old. Jane was educated at the Newby County Primary School, Scarborough High School for Girls and Doncaster High School for Girls.

Miss Harrison left the Doncaster School in May 1962 to accept employment with the Martins Bank Limited branch office at Baxter Gate, Doncaster. Later she was employed as a nanny in the United States and in Switzerland. She joined the British Overseas Airways Corporation in June 1966.

Miss Harrison’s remains were interred at Fulford Cemetery, Fulford, North Yorkshire, England. Her George Cross is on display at British Airways’ Speedbird Centre, Harmondsworth, Middlesex, England.

Marker at Fulford Cemetery.
Captain C. W. R. Taylor

Speedbird 712 was under the command of Captain Charles Wilson Ratcliffe Taylor, with Senior First Officer Francis Brendan Kirkland as copilot, and Acting First Officer John Chester Hutchinson as the third, relief, pilot. The flight engineer was Engineer Officer Thomas Charles Hicks. Also in the cockpit was Supervisory Captain Geoffrey Sidney Moss, who was conducting a periodic flight check of the crew.

Speedbird 712’s Chief Steward, Neville Cearl Davis-Gordon, was awarded the British Empire Medal for Gallantry (Civil Division) for his role in evacuating the passengers from the burning airliner.¹

Air Traffic Control Officer III John Michael Davis, who handled Speedbird 712’s emergency, was appointed an Ordinary Member of the Most Excellent Order of the British Empire (M.B.E.) in the Queen’s Birthday Honours for 1969.²

“Whiskey Echo” (G-ARWE) was a Boeing Model 707-465 Intercontinental airliner, serial number 18373, Boeing line number 302. The 707-465 was a variant of the 707-420 series, which was itself a version of the 707-320, with the primary change being the substitution of Rolls-Royce Conway Mk.508 turbofan engines in place of the standard Pratt & Whitney JT3C-6 turbojet engines. The airliner was operated by a minimum flight crew of three, and could carry 141 passengers with mixed-class seating, or a maximum of 189 passengers.

Boeing 707-465 G-ARWE in Cunard Eagle Airways livery, circa 1962. (www.britisheagle.net)

Whiskey Echo had originally been ordered by Cunard Eagle Airways and registered VR-BBZ (Bermuda). It made its first flight 27 June 1962. Cunard Eagle was taken over by BOAC as BOAC-Cunard in June 1962. Sisterships VR-BBW and VR-BBZ were reregistered in the United Kingdom as G-ARWD and G-ARWE.

A Boeing 707 Intercontinental (-420 series) airliner in BOAC-Cunard livery. (jjPostcards)

At the time of the accident, Whiskey Echo had flown 20,870 hours (TTAF).

Whiskey Echo’s  Number 2 engine was built in 1961 and had 14,917 hours total time since new (TTSN). It was last overhauled in March 1965 and had been flown 4,346 hours (TSIO) at the time of the accident. The engine had a normal time between overhauls (TBO) of 5,500 hours. The engine was removed from service due to excessive vibration in May 1965. Inspection revealed a fatigue failure of the Stage 8 high-pressure compressor stage. The engine was repaired, but during test runs, was still producing vibrations and was rejected based on BOAC standards. The vibrations did not exceed Rolls-Royce limits, though, and the engine was accepted for service. It was installed on another Boeing 707 and run for 1,415 hours, when it was removed for modification of turbine seals. The engine was installed at the Number 2 position on G-ARWE on 5 April 1968, three days before the accident.

The accident investigation found that the engine had suffered a fatigue failure of the Stage 5 low-pressure compressor wheel. Fragments of the wheel rim and blades were found inside the airport perimeter at the departure end of Runway 28 Left.

The engine’s 1¾-inch-diameter (44.45 millimeters) fuel supply line was severed by flying fragments. Jet fuel was pumped out of the open line at a rate of about 50 gallons (189 liters) per minute.

About 90 seconds after the fire started, Whiskey Echo’s Number 2 engine and part of its pylon fell away from the left wing.

According to the accident investigation report,

“Having initially started an Engine Failure Drill, the Flight Engineer changed directly to the Engine Fire Drill. According to his evidence, having completed Phase 1 of the Engine Fire Drill, which is required to be done from memory, he subsequently used his own copy of the check list to complete Phase II of the drill, including operation of the fire extinguisher transfer switch and pushing the discharge button for the second shot thirty seconds after the first. When the First Officer started to read the check list the Flight Engineer told him the check was already completed. . . .”

CIVIL AIRCRAFT ACCIDENT, Report on the Accident to Boeing 707-465 G-ARWE at Heathrow Airport, London, on 8th April 1968. ACCIDENTS INVESTIGATION BRANCH, Civil Accident Report No. EW/C/0203, Section 1.1 at Page 3

The engineer officer had failed to pull the fire fuel shut-off valve while following the emergency procedures check list. With the valve closed, the fuel in the supply line beyond the valve would have sustained the fire for only a few seconds. The airliner’s fire extinguisher bottles can only be discharged after the fire shut-off handle has been pulled.

Whiskey Echo had previously sustained an uncontained turbine blade failure. While taking off from Honolulu International Airport, Oahu, Hawaii, 21 November 1967, fragments of the turbine blades punctured a fuel tank, resulting in a fire. The takeoff was aborted, and emergency personnel at the airport put out the fire. The airplane was repaired, all four engines changed, and G-ARWE was returned to service.

A BOAC Boeing 707-436 Intercontinental, G-APFD, similar in appearance to 707-465 G-ARWE. (Pinterest)

The Boeing 707-420 series airliners were 152 feet, 11 inches (46.609 meters) long, with a wingspan of 142 feet, 5 inches (43.409 meters) and overall height 42 feet, 2 inches (12.852 meters) at its operating empty weight. The leading edges of the wings and tail surfaces are swept 35°. The fuselage has a maximum diameter of 12 feet, 8.0 inches (3.759 meters). The 707 International has a typical empty weight of 142,600 pounds (64,682 kilograms), and a maximum takeoff weight (MTOW) of  312,000 pounds (141,700 kilograms). The usable fuel capacity is 23,820 gallons (90,169 liters).

All 707-series aircraft are powered by four jet engines installed in nacelles below and forward of the wings on pylons. The -420 Internationals were powered by Rolls-Royce Conway Mk. 508 engines. The Rolls-Royce Conway (R.Co.12) is a two-spool, axial-flow, low-bypass turbofan engine. The engine has a 7-stage low- and 9-stage high-pressure compressor section, 12 interconnected combustion liners, with a single-stage high- and 2-stage low-pressure turbine. The Mk. 508 has a Maximum Continuous Power rating of 14,625 pounds of thrust (65.055 Kilonewtons), and 17,500 pounds of thrust (77.844 Kilonewtons) at 9,990 r.p.m., for Takeoff. The engine is 3 feet, 6.0 inches (1.067 meters) in diameter, 11 feet, 4.0 inches (3.454 meters) long, and weighs 4,542 pounds (2,060 kilograms).

The -420 series had a maximum cruise speed of 593 miles per hour 954 kilometers per hour) at 30,000 feet (9,144 meters)—0.87 Mach; and economical cruise speed of 550 miles per hour (885 kilometers per hour) at 35,000 feet (10668 meters).

Boeing built 1,010 Model 707 airplanes between 1957 and 1979. Of these, 37 were the 707-420 International variant.

A British Overseas Airways Corporation Boeing 707 International (-420 series) airliner, similar in appearance to G-ARWE. (Travel Update)

¹ Supplement to The London Gazette of Thursday, 7th August 1969. Friday, 8th August 1969, No. 44913, at Page 8212, Column 1.

² Supplement to The London Gazette of Friday, 6th June 1969. Saturday, 14th June 1969, No. 44863, at Page 5975, Column 1

© 2018, Bryan R. Swopes

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8 April 1954

De Havilland DH.106 Comet 1 G-ALYY, 1953. (Zoggavia)
De Havilland DH.106 Comet 1 G-ALYY, 1953. (Zoggavia)

8 April 1954: South African Airways Flight 201, a chartered British Overseas Airways Corporation de Havilland DH.106 Comet 1, aircraft registration G-ALYY, departed Rome at 1832 UTC, bound for Cairo. The Comet was under the command of Captain Wilhelm K. Mostert, with First Officer Barent J. Grove, Navigator Albert E. Sissing, Radio Officer Bertram E. Webstock, and Flight Engineer August R. Lagesen. Air Hostess Pamela L. Reitz and Flight Steward Jacobus B. Hok were in the passenger compartment with the 14 passengers.

As the airliner climbed toward 35,000 feet (10,668 meters), they made several position reports. Last heard from at 1907 UTC, radioing an expected arrival time at Cairo, the Comet disintegrated in flight and fell into the Tyrrhenian Sea. Searchers found a debris field and floating bodies the next day near the volcanic island of Stromboli. All 21 persons aboard were killed.

This was the second catastrophic failure of a DH.106 in just three months. BOAC immediately grounded its entire Comet fleet, and the British Air Ministry revoked the airliner’s certificate of airworthiness. Production of the airliner at de Havilland was halted.

The first crash had been presumed to be a result of an in-flight fire, and the second, an uncontained turbine engine failure. But an extensive investigation eventually determined that the cause of both crashes was the in-flight break up of the fuselage pressure hull. Metal fatigue of the fuselage was caused by the repeated expansion and contraction of pressurization cycles. Cracks in the aluminum skin formed at corners of the passenger compartment windows and then spread outward. This resulted in catastrophic explosive decompression.

The DH.106 Comet 1 was the first production version and was very similar to the two prototypes. It can be visually identified by its square passenger windows. It was flown by a pilot, co-pilot, flight engineer and navigator. The airliner could carry up to 44 passengers.

The airplane was 93 feet (28.346 meters) long with a wingspan of 115 feet (35.052 meters) and overall height of 29 feet, 6 inches (8.992 meters). The Comet 1 had a maximum takeoff weight of 110,000 pounds (49,895 kilograms). It was powered by four de Havilland Engine Company Ghost 50 centrifugal flow turbojet engines, producing 5,000 pounds of thrust, each. This gave it a cruising speed of 460 miles per hour (740 kilometers per hour) and cruise altitude of 42,000 feet (12,802 meters). The airliner’s range was 1,500 miles (2,414 kilometers).

Twelve DH.106 Comet 1 airliners were built.

The de Havilland Comet was the first commercial jet airliner and its introduction had revolutionized the industry. The two disasters were a blow from which the company never really recovered.

The first production de Havilland DH.106 Comet 1, G-ALYP, in formation with the two prototypes, G-ALVG and G-ALZK. G-ALYP also broke up in flight, 10 January 1954. (Ed Coates Collection)
The first production de Havilland DH.106 Comet 1, G-ALYP, in formation with the two prototypes, G-ALVG and G-ALZK. G-ALYP also broke up in flight, 10 January 1954. (Ed Coates Collection)

© 2016, Bryan R. Swopes

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5 March 1966

British Overseas Airways Corporation's Boeing 707-436 Intercontinental, G-APFE. (BOAC)
British Overseas Airways Corporation’s Boeing 707-436 Intercontinental, G-APFE. (British Airways)

5 March 1966: British Overseas Airways Corporation Speedbird 911, an around-the-world flight, departed Tokyo-Haneda Airport (HND) at 1:58 p.m., enroute Hong Kong-Kai Tak (HKG), with 113 passengers and 11 crew members. The airliner was a Boeing 707-436 Intercontinental, serial number 17706, with British registration G-APFE. It was nearly six years old, having been delivered 29 April 1960, and had 19,523 hours on the airframe.

Shortly before takeoff, the flight crew requested a change from an IFR flight plan to VFR, with a course that would take the airliner near Mount Fujiyama. The 707 climbed to an altitude of 16,000 feet (4,875 meters) as it approached the mountain from the southwest. The weather was very clear. A weather station on Mount Fuji recorded wind speeds of 60–70 knots (111–130 kilometers per hour).

Speedbird 911, Boeing 707 G-APFE, in a flat spin. The tail section and engines are missing, the right wing is broken and the airplane is trailing fuel vapor from ruptured tanks.
Speedbird 911, Boeing 707 G-APFE, in a flat spin. The tail section and engines are missing, the right wing is broken and the airplane is trailing fuel vapor from ruptured tanks. (JSDF)

Flying upwind toward Fujiyama at 320–370 knots (592–685 kilometers per hour), Speedbird 911 encountered severe Clear Air Turbulence that resulted in a catastrophic structural failure of the airframe. The vertical fin attachment failed and as it fell away, struck the left horizontal stabilizer, breaking it off. Next, the ventral fin and all four engine pylons failed due to extreme side loads. The 707 went in to a flat spin, trailing fuel vapor from ruptured tanks. The entire tail section broke away, the right wing failed, and the nose section came off.

The 707 left a debris field  that was 10 miles (16 kilometers) long. Speedbird 911 crashed in a forest on the lower flanks of Mount Fujiyama at about the 3,500 foot (1,066 meter) level. The forward section crashed about 1,000 feet (300 meters) away from the main wreckage. All 124 persons aboard were killed.

Disintegrating Speedbird 911 trails fuel vapor as it falls toward Mount Fujiyama, 5 March 1966.
Disintegrating Speedbird 911 trails fuel vapor as it falls toward Mount Fujiyama, 5 March 1966. (JSDF)

PROBABLE CAUSE: “The aircraft suddenly encountered abnormally severe turbulence over Gotemba City which imposed a gust load considerably in excess of the design limit.”

The accident was photographed by the Japanese Self Defense Forces from the East Fuji Maneuver Area, located in the foothills of the volcano. A passenger aboard Speedbird 911 had been filming with an 8 mm movie camera. The camera and film were recovered from the wreckage and the film was developed as part of the investigation. The film showed that the aircraft had experienced severe turbulence immediately before the accident.

A U.S. Navy Douglas A-4 Skyhawk was sent to look for the accident site. When the fighter approached Mount Fujiyama, it also encountered severe turbulence, to the point that the pilot feared the small fighter would break up in flight. After returning to base, the A-4 was grounded for inspection. Its accelerometer indicated that it had experienced acceleration forces ranging from +9 Gs to -4 Gs.

Mount Fujiyama, an active stratovolcano, i steh tallest mountain in Japan, at 12,389 feet (3,776.24 meters). It i sapproximately 62 miles (100 kilometers) southwest of Tokyo on the island of Hinshu.
Mount Fujiyama, an active stratovolcano, is the tallest mountain in Japan, at 12,389 feet (3,776.24 meters). It is approximately 62 miles (100 kilometers) southwest of Tokyo on the island of Honshu. (Alpsdake)

© 2017, Bryan R. Swopes

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10 January 1954

The first production de Havilland DH.106 Comet 1, G-ALYP, in formation with the two prototypes, G-ALVG and G-ALZK. G-ALYP also broke up in flight, 10 January 1954. (Ed Coates Collection)
The first production de Havilland DH.106 Comet 1, G-ALYP, in formation with the two prototypes, G-ALVG and G-ALZK. (Ed Coates Collection)

10 January 1954: British Overseas Airways Corporation Flight 781 departed Ciampino Airport, Rome, Italy, at 0931 UTC, enroute to Heathrow Airport, London, England. The airliner was the first production de Havilland DH.106 Comet I, G-AYLP, serial number 06003. The flight crew were Captain Alan Gibson, First Officer William John Bury, Engineer Officer Frances Charles McDonald and Radio Officer Luke Patrick McMahon. There were two flight attendants, Frank L. Saunders and Jean Evelyn Clark, and 29 passengers. After departure began climbing toward its cruise altitude of 27,000 feet (8,230 meters).

At 0951 UTC, 20 minutes after takeoff, Captain Gibson was conversing by radio with another BOAC flight. It is presumed that Flight 781 had reached its cruise altitude. Captain Gibson was heard to say, “George How Jig from George Yoke Peter [the phonetic alphabet call signs for Argonaut G-ALHJ and Comet G-AYLP] did you get my—” and the transmission suddenly ended. Nothing more was heard from Flight 781 and it did not arrive at its destination.

Several fishermen had seen the airliner crash into the Mediterranean Sea near the island of Elba and recovered bodies of the victims, which were found to have suffered the effects of explosive decompression.

Wreckage of Comet G-AYLP was found on the sea floor, 12 February 1954, and it was apparent that the airliner had broken up in flight. Consideration was given to the possibility of a bomb having been placed aboard, or that an uncontained turbojet engine failure had penetrated the pressure cabin resulting in a structural failure of the fuselage through explosive decompression.

De Havilland Comet 1 G-AYLP (Crash-aerien)
De Havilland Comet 1 G-AYLP (www.crash-aerien.news)

After two prototypes, G-AYLP was the first production Comet. It was the fourth DH.106 to be lost in just over fourteen months. With the cause of Flight 781’s crash undetermined, B.O.A.C. grounded its remaining Comet airliners. De Havilland engineers recommended more than 60 modifications to improve perceived weaknesses in the Comet fleet.

Extensive testing by the Royal Aircraft Establishment determined that the Comet’s pressurized fuselage could be expected to fail from metal fatigue after 1,000 pressurization/depressurization cycles. G-AYLP had experienced 1,290 pressurization cycles during the 3,681 hours it had flown since its first flight, 9 January 1951.

The Royal Aircraft Establishment placed DH.106 Comet I G-AYLU in a water tank to conduct pressurization tests. (lessonslearned.faa.gov)
The Royal Aircraft Establishment placed DH.106 Comet I G-AYLU in a water tank to conduct pressurization tests. (lessonslearned.faa.gov)

Reconstruction of G-ALYP’s fuselage revealed that a fatigue crack had begun at a rivet hole of a square opening for the airplane’s automatic direction finder antenna. With the differential in pressure from inside and outside the passenger cabin, this crack had spread along the top of the fuselage through a passenger window and back to to the elevators at the tail. The fuselage structure then failed explosively and the airplane’s tail section came off. The wings then failed and fuel carried inside caught fire. The cockpit section tore away from the remaining fuselage section.

In reporting the Probable Cause of the destruction of G-AYLP, the committee wrote,

We have formed the opinion that the accident at Elba was caused by structural failure of the pressure cabin, brought about by fatigue. We reach this opinion for the following reasons:

(i) The low fatigue resistance of the cabin has been demonstrated by the test described in Part 3, and the result is interpretable as meaning that there was, at the age of the Elba aeroplane, a definite risk of fatigue failure occurring.

(ii) The cabin was the first part of the aeroplane to fail in the Elba accident.

(iii) The wreckage indicates that the failure in the cabin was the same basic type as that produced in the fatigue test.

(iv) This explanation seems to us to be consistent with all the circumstantial evidence.

(v) The only other defects found in the aeroplane were not concerned at Elba, as demonstrated by the wreckage. Report of the Public Inquiry into the causes and circumstances of the accident which occurred on the 10th January 1954, to the Comet aircraft G-AYLP.

Four months later, April 8 1954, a Comet 1 operated by South African Airways as Flight 201 from Rome to Cairo, G-ALYY, crashed near Naples, Italy with the deaths of all 21 persons aboard. The airplane had explosively broken up at an altitude of 35,000 feet (10,668 meters).

The de Havilland DH.106 Comet fleet was grounded and the Ministry of Transportation withdrew the type’s Certificate of Airworthiness. Production of the airliner at Hatfield came to a stop.

BOAC's DH.106 Comet I G-ALYW in long term storage at Heathrow, 12 September 1954. (RuthAS via Wikipedia)
BOAC’s DH.106 Comet I G-ALYW in long term storage at Heathrow, 12 September 1954. (RuthAS via Wikipedia)

De Havilland redesigned the Comet, and as the Comet 4 it had a successful career in airline operation. It eventually lost out to the faster, longer range Boeing 707 and Douglas DC-8. Production ceased in 1964 and B.O.A.C. retired its last Comet in 1965.

The Comet was again redesigned as the Hawker Siddeley Nimrod maritime reconnaissance aircraft.

© 2016, Bryan R. Swopes

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