19 April 2006: Former experimental test pilot Albert Scott Crossfield, Jr., was enroute from Prattville, Alabama, to Manassas, Virginia. Crossfield was flying his personal Cessna 210A, N6579X. The Cessna was cruising at 11,000 feet (3,353 meters) under Instrument Flight Rules (IFR), and under the control of the Atlanta Air Route Traffic Control Center (ARTCC).

During the flight, he encountered a Level 6 thunderstorm.

Crossfield requested to deviate from his planned course to avoid the severe turbulence. Atlanta Center authorized his request and he began to turn. Approximately 30 seconds later, at 11:10 a.m., radar contact was lost near Ludville, Georgia. The last indication was that the Cessna was descending through 5,500 feet (1,676 meters).

The wreckage of N6579X was located the following day by a Civil Air Patrol search team, 3.3 nautical miles (6.1 kilometers) northwest of Ludville at an elevation of 1,269 feet (386.8 meters) above Sea Level. [N. 34° 30.767′, W. 84° 39.492′] The airplane had descended through the forest canopy nearly vertically and created a crater approximately 4½ feet (1.4 meters) deep and 6 feet (1.8 meters) across. Albert Scott Crossfield’s body was inside.

N6579X was a Cessna Model 210A, serial number 21057579, built in 1960 by the Cessna Aircraft Company, Inc., of Wichita Kansas. It was a six-place, single-engine, high-wing monoplane with external struts to brace the wings, and retractable, tricycle landing gear. The airplane was certified for instrument flight by a single pilot. At the time of the crash, N6579X had been flown 4,987.4 hours, total time since new (TTSN).

The Cessna 210A was 28 feet, 2 inches (8.585 meters) long with a wingspan of 36 feet, 6 inches (11.125 meters) and overall height of 9 feet, 7 inches (2.921 meters). The airplane had an empty weight of 1,839 pounds (834.2 kilograms) and maximum gross weight of 2,900 pounds (1,315.4 kilograms). It had a fuel capacity of 65 gallons (246 liters), with 10 gallons (37.9 liters) unusable, and 12 quarts of engine oil (11.4 liters).

N6579X was powered by an air-cooled, fuel-injected, 471.239-cubic-inch-displacement (7.722 liters) Teledyne Continental IO-470-E horizontally-opposed six-cylinder direct-drive engine with a compression ratio of 8.6:1. The engine was rated at 260 horsepower at 2,625 r.p.m. for takeoff, using 100LL aviation gasoline. It weighed 429 pounds (195 kilograms). This engine, serial number 77583-0-E, was original to the airplane and accumulated 4,987.4 hours, total time since new (TTSN). It had been overhauled by Victor Aviation, Palo Alto, California, 1,259.8 hours prior to the accident (TSO). A three-bladed McCauley constant-speed propeller with a diameter of 6 feet, 10 inches (2.083 meters) was installed in 2005.

The Cessna Model 210A has a maximum structural cruise speed (V_NO) of 175 miles per hour (282 kilometers), and maximum speed (V_NE) of 200 miles per hour (322 kilometers per hour). Maneuvering speed, which should be used in turbulent conditions, is 130 miles per hour (209 kilometers per hour). The 210A has a maximum rate of climb of 1,300 feet per minutes (6.6  meters per second) and service ceiling of 20,700 feet (6,309 meters). Its maximum range is 1,284 miles (2,066 kilometers).

Albert Scott Crossfield, Jr., was born 2 October 1921 at Berkeley, California. He was the second of three children of Albert Scott Crossfield, a chemist who was employed as the superintendant of the Union Oil Company refinery in Wilmington, California, and Lucia M. Dwyer Crossfield.

When he was five years old, young “Scotty” contracted pneumonia. He was comatose for a while and was not expected to survive, but after several weeks he began to recover. A year later, he again became seriously ill, this time with rheumatic fever. He was confined to total bed rest for four months, and continued to require extensive bed rest until he was about ten years old. It was during this time that he became interested in aviation.

Scott Crossfield attended Boistfort Consolidated School, southwest of Chehalis, Washington, graduating in 1939, and then studied engineering at the University of Washington until taking a job at Boeing in late 1941. During this time, Scotty learned to fly in the Civilian Aviation Training Program.

The week following the attack on Pearl Harbor and the United States’ entry into World War II, Scott Crossfield enlisted as an aviation cadet in the United States Army Air Corps. After numerous delays, he joined the United States Navy on 21 February 1942, and resigned from the Air Corps. He began aviation cadet training at NAS Sand Point, near Seattle, and then was sent to NAS Corpus Christi, Texas. In December 1942, he graduated, received his gold Naval Aviator wings and was commissioned as an Ensign, United States Naval Reserve.

Ensign Crossfield was assigned to NAS Kingsville, near Kingsville, Texas, as an advanced bombing and gunnery instructor.

In April 1943 at Corpus Christi, Texas, Ensign A. Scott Crossfield married Miss Alice Virginia Knoph of Seattle. They would have nine children.

Ensign Crossfield served as a gunnery instructor for two years. He was promoted to Lieutenant (junior grade), 1 March 1944. In 1945 he was transferred to Air Group 51 in the Hawaiian Islands, which was preparing for the invasion of Japan. Crossfield was promoted to Lieutenant, 1 August 1945, while serving aboard the Independence-class light aircraft carrier USS Langley (CVL-27). With the end of World War II, though, the Navy was cutting back. Lieutenant Crossfield was released from active duty 31 December 1945.

Following the War, Scotty returned to the University of Washington to complete his degree. He took a part time job operating the University’s wind tunnel. At the same time, he remained in the Naval Reserve, assigned to VF-74, a fighter squadron which flew both the Grumman F6F Hellcat and Chance Vought F4U Corsair out of NAS Sand Point, back where his naval career began.

Crossfield graduated from the University of Washington with a bachelor’s degree in aeronautical engineering in June 1949, and a master’s degree in 1950.

In 1950 Crossfield joined the National Advisory Committee for Aeronautics (NACA) as a research test pilot at the High-Speed Flight Station, Edwards Air Force Base, California. He flew the Republic YF-84, F-84F Thunderstreak, and North American Aviation F-86 Sabre. Crossfield made 25 flights in the delta-winged Convair XF-92A, which he described as “the worst flying airplane built in modern times.” He also flew the Northrop X-4 and Bell X-5. He made 17 flights conducting stability tests in the Douglas D-558-1 Skystreak. Scotty made 65 flights in the North American Aviation F-100A Super Sabre, including a test series which discovered a fatal flaw which led to the death of North American’s chief test pilot, George S. Welch.

Crossfield is known as a rocketplane pilot. He made 10 flights in the Bell X-1, 89 in the Douglas D-558-II Skyrocket, and 14 in the North American Aviation X-15. He became the first pilot to exceed Mach 2 when he flew the Skyrocket to Mach 2.005, 20 November 1953.

Crossfield flew for NACA for approximately five years. During that time, approximately 500 flights were made at Edwards by NACA test pilots. Scott Crossfield flew 181 of them.

Scott Crossfield left NACA in 1956 to join North American Aviation, Inc., as chief engineering test pilot for the X-15 project. Between 8 June 1959 and 6 December 1960, he made fourteen flights in the X-15. He reached a maximum speed of Mach 2.97 and altitude of 88,116 feet (26,858 meters). Once the contractor’s flight tests were completed and the rocketplane turned over to the U.S. Air Force and NACA, the customers’ test pilots, Joe Walker and Major Robert M. White, took over.

Albert Scott Crossfield made 113 flights in rocket-powered aircraft, more than any other pilot.

After completing his work on the X-15, Crossfield followed Harrison (“Stormy”) Storms, who had been the Chief Engineer of North American’s Los Angeles Division (where the X-15 was built) to the Space and Information Systems Division in Downey, California, where he worked in quality assurance, reliability engineering and systems testing for the Apollo Command and Service Modules and the Saturn S-II second stage.

Crossfield left North American at the end of 1966, becoming Vice President for Technological Development for Eastern Air Lines. In this position, he flew acceptance tests for new Boeing 720 and 727 airliners at Boeing in Seattle.

In The X-15 Rocket Plane, author Michelle Evans quoted Crossfield as to why he had not entered NASA’s space program as an astronaut:

    One question that pressed was, with his love of flight and the early responsibility of going into space with the X-15, why would Scott not apply to the NASA astronaut office? He explained, “[Dr.] Randy Lovelace and General [Donald] Flickinger were on the selection board. They took me to supper one night and asked me not to put in for astronaut. I asked them, ‘Why  not?’ and they said, ‘Well, we’re friends of yours. We don’t want to have to turn you down.’ I asked, ‘Why would you have to turn me down?’ and they said, ‘You’re too independent.’ “

—The X-15 Rocket Plane: Flying the First Wings into Space, by Michelle, Evans, University of Nebraska Press, 2013, Chapter 1 at Page 33.

The remains of Albert Scott Crossfield are interred at the Arlington National Cemetery.

© 2017, Bryan R. Swopes

19 April 1955:¹ Lockheed test pilot Herman Richard (“Fish”) Salmon was flying the second prototype Lockheed XF-104 interceptor, 53-7787, conducting tests of the General Electric T171 Vulcan gun system.

At 47,000 feet (14,326 meters), Salmon fired two bursts from the T171. On the second burst, vibrations from the gun loosened the airplane’s ejection hatch, located beneath the cockpit, resulting in explosive decompression.

The Associated Press reported:

Test Pilot Leaps From New Jet

     INYOKERN, Calif., April 20 (AP)—Herman R. (Fish) Salmon, former racing pilot and now a top test pilot, bailed safely from one of the Air Force’s hot new F104 jet fighters over the Mojave dessert[sic]Tuesday.

He was  spotted on the desert after a two-hour search by military planes and brought to the Naval ordinance [sic] test station here for a physical examination. A preliminary checkup indicated he was not injured.

     Salmon, 41, was on a routine test flight when he hit the silk. Authorities gave no hint what happened to the supersecret plane to make the bailout necessary. The craft’s height at the time it was abandoned was not given. The plane’s top speed has been unofficially estimated at 1,200 m. p. h.

     Wreckage of the F104, one of two prototypes now being tested by Lockheed Aircraft Corp. for the Air Force, was found several miles south of the China Lake area.

     A Lockheed spokesman said Salmon, of Van Nuys, Calif., was spotted by a search plane and apparently picked up by a Navy helicopter and flown here. Salmon took off on the test flight from Palmdale, about 70 miles south of here.

— Reno Evening Gazette, Volume LXXIX, Number 21, Wednesday, 20 April 1955, Page 24 at Columns 5–7.

Fish Salmon was wearing a David Clark Co. T-1 capstan-type partial-pressure suit and International Latex Corporation (I.L.C. Dover) K-1 helmet for protection in just such an emergency. The capstans are pneumatic tubes surrounded by fabric lacings, running along the arms, torso and legs. As the tubes inflated, the lacings pulled the fabric of the suit very tight and applied pressure to his body as a substitute for normal atmospheric pressure. The partial-pressure garment also enclosed his head, with a fiberglass helmet and a clear visor or face plate providing for vision.

The sudden loss of cabin pressure and drop to subfreezing temperatures caused Salmon’s face plate to fog over. Inflating air bladders pushed his helmet high on his head.  The cockpit was filled with dust, fiberglass insulation and other debris. All this restricted his visibility, both inside and outside the airplane. The very tight pressure suit restricted his movements.

Fish Salmon cut the throttle, opened the speed brakes and began a descending turn to the left to reach a lower altitude. By the time he had reached 15,000 feet (4,572 meters) he had been unable to find a place on the desert floor to make an emergency landing. It was time to leave the crippled XF-104.

At 250 knots (288 miles per hour/463 kilometers per hour) the ejection seat fired Salmon out of the bottom of the cockpit. He had to open his parachute manually (the seat timer did not operate) and he made a safe landing.

The prototype XF-104 impacted the desert approximately 73 miles (117 kilometers) east-northeast of Edwards Air Force Base. It was completely destroyed. Fish Salmon landed about 2 miles (3.2 kilometers) away. He was found two hours later and rescued by an Air Force helicopter.

Occasionally, a satisfied user thanked the researchers at the Aero Medical Laboratory. One of these was Lockheed test pilot Herman R. “Fish” Salmon. On April 14, 1955, ¹ Salmon was flying the second XF-104 (53-7787) at 47,500 feet while wearing a T-1 suit, K-1 helmet, and strap-fastened boots. As he triggered the General Electric M61 Vulcan 20 mm cannon for a test firing, severe vibrations loosened the floor-mounted ejection hatch and the cockpit explosively depressurized at the same time as the engine flamed out. The suit inflated immediately. Repeated attempts to restart the engine failed, and Salmon ejected at 15,000 feet. Fish reported, “I landed in a field of rocks ranging from one foot to five feet in diameter. My right arm was injured and my head struck a rock. The K-1 helmet hard shell was cracked, but there was no injury to my head. It took me 10 to 15 minutes to get out of the suit with my injured arm. Rescue was effected by helicopter approximately two hour after escape.” Salmon reported that the K-1 helmet was excellent for rugged parachute landings, and his only complaint was that the visor may impair vision at extreme altitudes.”

—Dressing for Altitude: U.S. Aviation Pressure Suits—Wiley Post to Space Shuttle, by Dennis R., Jenkins, National Aeronautics and Space Administration SP–2011–595, Washington, D.C., 2012, Chapter 4 at Page 141.

There were two Lockheed XF-104 prototypes. Initial flight testing was performed with 083-1001 (USAF serial number 53-7786). The second prototype, 083-1002 (53-7787) was the armament test aircraft. Both were single-seat, single-engine supersonic interceptors. The XF-104 was 49 feet, 2 inches (14.986 meters) long with a wingspan of 21 feet, 11 inches (6.680 meters) and overall height of 13 feet, 6 inches (4.115 meters). The prototypes had an empty weight of 11,500 pounds (5,216 kilograms) and maximum takeoff weight of 15,700 pounds (7,121 kilograms).

The production aircraft was planned for a General Electric J79 turbojet but that engine would not be ready soon enough, so both prototypes were designed to use a Buick-built J65-B-3, a licensed version of the British Armstrong Siddeley Sapphire turbojet engine. XF-104 53-7787 had been built with an afterburning Wright J65-W-7 turbojet, rated at 7,800 pounds of thrust, and 10,200 pounds of thrust with afterburner. The J65 was a single-shaft axial-flow turbojet with a 13-stage compressor, annular combustion chamber, and 2-stage turbine.

The XF-104 had a maximum speed of 1,324 miles per hour (2,131 kilometers per hour), a range of 800 miles (1,287 kilometers) and a service ceiling of 50,500 feet (15,392 meters).

The General Electric T171 Vulcan was a prototype 6-barrelled 20 mm “Gatling Gun” automatic cannon. The barrels were rotated at high speed by a hydraulic drive. The gun is capable of firing 6,000 rounds per minute. The initial production version was designated M61. The cannon system was installed in a weapons bay on the left side of the F-104, between the cockpit and engine intakes. The production F-104C carried 750 rounds of ammunition.

The first prototype Lockheed XF-104, 53-7786, was also destroyed, 11 July 1957, when the vertical fin was ripped off by uncontrollable flutter. The pilot, William C. Park, safely ejected.

¹ Reliable sources give the date of this incident as both 14 April and 19 April. Contemporary news reports, published Wednesday, 20 April 1955, say that the accident took place “yesterday” and “Tuesday,” suggesting that the correct date is 19 April.

© 2017, Bryan R. Swopes

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.

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.

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.

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.

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.

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.

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

8 April 1954: Suid-Afrikaanse Lugdiens (South African Airways) Flight 201, a chartered British Overseas Airways Corporation de Havilland DH.106 Comet 1, departed Rome at 1832 UTC, bound for Cairo.

The Comet, registered G-ALYY, was under the command of Captain Wilhelm Karel Mostert, with First Officer Barent Jacobus Grove, Navigator Albert Escourt Sissing, Radio Officer Bertram Ernest Webstock, and Flight Engineer August Ranwald Lagesen. Air Hostess Pamela Lucia Reitz and Flight Steward Jacobus Bruwer Kok 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. “Owing to the absence of wreckage, we are unable to form a definite opinion on the cause of the accident near Naples, but we draw attention to the fact that the explanation offered for the accident at Elba [Comet G–ALYP, 10 January 1954] appears to be applicable to that at Naples.” ¹ Metal fatigue of the fuselage was caused by the repeated expansion and contraction of pressurization cycles. Cracks in the aluminum skin formed at stress points at the 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 27 feet, 10 inches (8.484 meters). The wings were swept 20°, as measured at ¼ chord. The fuselage had a maximum outside diameter of 10 feet, 3 inches (3.124 meters), and 9 feet, 9 inches (2.972 meters) inside. The Comet 1 had an authorised maximum all-up weight of 107,000 pounds (48,534 kilograms).

The Comet I was powered by four de Havilland Engine Co., Ltd., Ghost 50 Mk.I turbojet engines. The Ghost was a single-shaft centrifugal-flow turbojet with a single-stage compressor, 10 combustion chambers and a single-stage turbine. It was rated at 5,000 pounds of thrust (22.24 kilonewtons) at 10,250 r.p.m. The Ghost 50 had a maximum diameter of 4 feet, 5 inches (1.346 meters), length of 10 feet, 1 inch (3.073 meters) and dry weight of 2,218 pounds (1,006 kilograms). When first placed in service, the engines required a combustion chamber inspection at 125 hour intervals. A complete overhaul was required every 375 hours. The Ghost was the first turbojet certified for civil airliner operations.

The Comet I had a maximum cruising speed of 490 miles per hour (789 kilometers per hour), True Air Speed, and operating altitude of 35,000 to 40,000 feet (10,668–12,192 meters). The airliner’s fuel capacity was 6,050 Imperial gallons (27,504 liters, or 7,266 U.S. gallons) giving a practical stage length of 2,140 miles (3,444 kilometers). The maximum range was 3,860 miles (6,212 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.

¹ MINISTRY OF TRANSPORT AND CIVIL AVIATION, CIVIL AIRCRAFT ACCIDENT. Report of the Court of Inquiry into the Accidents to Comet G–ALYP on 10th January, 1954 and Comet G–ALYY on 8th April, 1954, Part IX: THE COURT’S CONCLUSION AS TO CAUSE OF ACCIDENT, at Pages 46–47

© 2024, Bryan R. Swopes

7 April 1961: Boeing B-52B-30-BO Stratofortress 53-380, assigned to the 95th Bombardment Wing and named Ciudad Juarez, departed Biggs Air Force Base, El Paso, Texas on a training mission. The aircraft commander was Captain Donald C. Blodgett.

The flight took Ciudad Juarez over New Mexico where they were intercepted by a flight of two North American F-100A Super Sabres of the New Mexico Air National Guard, also on a training flight.

Captain Dale Dodd and 1st Lieutenant James W. van Scyoc had departed Kirtland Air Force Base, Albuquerque, New Mexico. Each of their Super Sabres were armed with two GAR-8 Sidewinder air-to-air missiles (later redesignated AIM-9B Sidewinder). Their assignment was to practice ground-controlled intercepts of the B-52.

Each F-100 made five passes at the B-52, flying at 34,000 feet (10,363 meters) over central New Mexico. Their Sidewinder infrared-seeking sensors would lock on to the heat of the B-52’s engines and give an audible signal to the fighter pilot that the target had been acquired. Safety precautions required that a circuit breaker be pulled and a firing switch be left in the off position. Before each pass, ground controllers had the pilots verify that the missiles were safed.

As the training session came to an end, Lieutenant van Scyoc, flying F-100A-20-NA Super Sabre 53-1662, announced, “OK, Wing, one more run then we’ll go home.” The seeker heads of his Sidewinders locked on to the B-52, but then one of the missiles fired.

Van Scyoc radioed, “Look out! One of my missiles is loose!” Captain Blodgett heard the warning, but before he could begin evasive maneuvering, the Sidewinder impacted the inboard engine nacelle under the bomber’s left wing, blowing the wing completely off. The B-52 immediately rolled over and went into a spin. 52-380 disappeared into the clouds 10,000 feet (3,048 meters) below.

The co-pilot of Ciudad Juarez, Captain Ray C. Obel, immediately ejected. His ejection seat was thrown through a hatch opening in the cockpit ceiling. Because of the high altitude, this sudden opening in the fuselage resulted in explosive decompression. The crew chief, Staff Sergeant Manuel A. Mieras, had been standing on a crew ladder behind the pilots which led to the lower deck where the navigator and bombardier were located. Sergeant Mieras was sucked up through the hatch. His left leg was so badly injured that it later had to amputated.

Captain Blodgett was pinned against the cockpit side by the g forces of the rapidly spinning bomber. He later reported:

I heard van Scyoc call “Look out! My missile’s fired.” We were on autopilot and I grabbed the controls just as the missile hit. There was a tremendous shudder and the aircraft banked left steeply. Electrical equipment in the right side of the cockpit caught fire. My copilot ejected with the aircraft in a 90° bank and in all the confusion I didn’t realize he had gone. I tried to reach the alarm bell control between the two seats to order the crew to bail out, while holding the controls with my left hand to maintain full right aileron and rudder. I didn’t realize the wing had gone and the aircraft wasn’t responding at all; it began to spin down into the clouds and I still wasn’t sure that I had hit the alarm. Later, my crew chief said he had seen the red light flashing as he sat on the steps to the lower cabin. With g-forces building up tremendously, pinning me to my seat I could not raise my right hand from its position near the bail-out alarm but could move it sideways to the ejection handle. The hatch fired and the seat threw me up fifty feet with the B-52 at 600 knots. The slipstream tore off my helmet as I left the aircraft. There was another explosion and I went through a ball of fire — it felt like being in an oven. Immediately after that I went through a “bath” of JP-4 fuel as the fuel tanks had broken up in this second explosion. At least this put out the fire but now I was soaking wet with fuel and still on the ejection seat. Assuming a seat malfunction (they told me afterwards I was holding on to it) I reached out to unfasten the lap belt when suddenly I flew out of the seat. However, the inter-phone cord wrapped around my leg so now I was going down through the clouds with a 650 pound seat hooked to my leg. I thought it would rip my leg off and I managed to claw the cord free. By now I was falling in a cloud of debris — and a blizzard. I released my survival gear pack, which also automatically released the survival raft. This was suspended about 40 feet below me and, with all the updrafts in the clouds due to the bad weather it acted like a sail, pulling me round in a 180° arc. I thought, ‘If I hit the ground sideways, this is it!’ I couldn’t get to my knife to cut it free but I soon got out of the turbulence and began to fall straight. 

When I ejected, my left arm hit the hatch putting a big gash in it. The blood was pouring out of this and I was holding this with my right hand, trying to stop the bleeding. Suddenly I saw something white and I hit the ground in a downswing of the parachute and a 30 knot wind. It felt like jumping off a two-story building. I hit so hard that everything in my survival kit: the radio, mirrors, etc., was broken apart from the survival rifle. My original intentions were to get the radio going and tell that fighter pilot what I thought of him. . . .

—Aviation Safety Network, https://aviation-safety.net/wikibase/wiki.php?id=48341

Ciudad Juarez impacted on Mount Taylor, an 11,305 foot (3,446 meter) stratovolcano northeast of Grants, New Mexico, and left a crater 75 feet (23 meters) deep. Captain Peter J. Gineris, navigator, Captain Stephen C. Carter, bombardier, and 1st Lieutenant Glenn V. Blair, electronic countermeasures, did not escape.

Captain Blodgett suffered a fractured pelvis, Captain Obel, a broken back. The tail gunner, Staff Sergeant Ray A. Singleton, was badly burned.

Sergeant Singleton located Captain Blodgett and they were both rescued by helicopter later that day. It would be two days before Captain Obel and Sergeant Mieras were located.

An investigation determined that moisture condensation inside a worn electrical plug had caused a short circuit which fired the Sidewinder. Lieutenant van Scyoc was completely exonerated of any blame for the accident.

The AIM-9B Sidewinder was the first production version of the Raytheon Sidewinder 1A. It was 9 feet, 3.5 inches (2.832 meters) long with a diameter of 5 inches (12.7 centimeters). The span of the fins was 1 foot, 10 inches (55.9 centimeters). The AIM-9B weighed 155 pounds (70.3 kilograms). The missile was powered by a Thiokol Mk. 17 rocket engine which produced 4,000 pounds of thrust for 2.2 seconds. It could achieve a speed of Mach 1.7 over its launch speed, or about Mach 2.5. The maximum range was 2.9 miles (4.82 kilometers). It carried a 10 pound (4.54 kilogram) blast fragmentation warhead with an infrared detonator. The lethal range was approximately 30 feet (9.1 meters).

The Sidewinder is named after a species of rattlesnake, Crotalus cerastes, a pit viper common in the southwest United States and northern Mexico. The snake uses a heat-sensing organ on top of its head to hunt.

© 2016, Bryan R. Swopes

5 April 1950: While on a test flight following an engine change, a United States Navy Martin JRM-3 Mars seaplane, Marshall Mars, Bu. No. 76822, suffered an engine fire (inboard, left wing) and made an emergency landing at Ke’ehi Lagoon, off Diamond Head, Hawaii. The airplane’s crew was rescued but the airplane exploded and sank.

The wreck was discovered on the sea floor in August 2004 at a depth of approximately 1,400 feet (427 meters).

The Martin JRM Mars was a large four-engine flying boat transport built by the Glenn L. Martin Company for the U. S. Navy. originally designed as a patrol bomber, the prototype XPB2M-1 Mars made its first flight on 3 July 1942, Only five transport variants were built, four designated JRM-1, with the last one being a JRM-2. Each airplane was given an individual name derived from the names of island chains in the Pacific Ocean: Marianas Mars, Hawaii Mars, Philippine Mars, Marshall Mars and Caroline Mars. These airplanes were used to transport personnel and cargo between the West Coast of the United States and the Hawaiian Islands. All were upgraded to JRM-3.

The Martin JRM-2 Mars had a normal crew of 4, with accommodations for a relief crew. It was designed to carry 138 combat troops or 34,000 pounds (15,422 kilograms) of cargo. It was 120 feet, 3 inches (36.652 meters) long with a wingspan of 200 feet, 0 inches (60.960 meters) and height of 43 feet, 8 inches (13.310 meters), with beaching gear. The wing area was 3,686 square feet (342.4 square meters). The flying boat had an empty weight of 80,701 pounds (36,605 kilograms) and a maximum takeoff weight (MTOW) 0f 165,000 pounds (74,843 kilograms).

A NASA publication states, “A zero-lift drag coefficient of 0.0233 and a maximum lift-drag ratio of 16.4 made the JRM the most aerodynamically efficient of any of the flying boats. . . .”

The Martin Mars was powered by four air-cooled, supercharged, direct-fuel-injected, 3,347.662-cubic-inch-displacement (54.858 liter) Wright Aeronautical Division R-3350-24WA (Cyclone 18 825C18BD1) (also known as the Duplex-Cyclone), a two-row 18-cylinder radial engines with a compression ratio of 6.70:1 and water/alcohol injection. This engine has a normal power rating of 2,000 horsepower at 2,400 r.p.m at 5,500 feet (1,676 meters) and 1,800 horsepower at 2,400 r.p.m. at 15,000 feet (4,572 meters). The engine’s takeoff power rating is 2,500 horsepower at 2,900 r.p.m. 100/130 octane aviation gasoline was required. The engines drove four-bladed 16 foot, 8 inch (5.080 meter) Curtiss Electric variable-pitch propellers through a 0.4375:1 gear reduction. (After modification to the JRM-3, the propellers on the inboard engines were reversible.) The R-3350-24WA is 6 feet, 8.58 inches (2.047 meters) long, and 4 feet, 6.13 inches (1.375 meters) in diameter. Its dry weight is 2,822 pounds (1,280 kilograms).

The JRM-3 had a cruise speed of 165 knots (190 miles per hour/306 kilometers per hour) and a maximum speed of 211 knots (243 miles per hour/391 kilometers per hour) at 15,600 feet (4,755 meters). The service ceiling was 19,700 feet (6,005 meters) and its range was 3,790 nautical miles (4,361 statute miles/7,019 kilometers).

© 2019, Bryan R. Swopes

4 April 1975: Operation Babylift. As the end of the Vietnam War approached, it was decided to evacuate 2,000 orphans, most in the care of an American hospital in Saigon, Republic of South Vietnam, and to take them to safety within the United States. The first flight was aboard a U.S. Air Force Lockheed C-5A Galaxy heavy lift transport, serial number 68-0218, piloted by Captains Dennis W. Traynor III and Tilford Harp.

A medical team from Clark Air Base, The Philippines, commanded by First Lieutenant Regina Claire Aune, Nurse Corps, United States Air Force, was aboard when the huge transport plane landed at Tan Son Nhut Air Base in Saigon. When it was discovered that there would be about 250 orphans aboard, many of them sick or injured, another medical team from a C-141 Starlifter volunteered to accompany Lieutenant Aune’s team for the outbound flight.

When the Galaxy took off from Saigon at 4:00 p.m., there were 328 people aboard, including flight crew, medical teams, orphans and their escorts, as well as other U.S. personnel.

The C-5A quickly climbed to 23,000 feet (7,010 meters). Just a few minutes after takeoff, the locks of the rear loading ramp failed. Explosive decompression hurled people and equipment throughout the airplane which instantly filled with fog. Lieutenant Aune was thrown the entire length of the upper deck. The airplane was severely damaged with two hydraulic systems inoperative and many flight control cables severed.

The pilots could only control the airplane with engine thrust. They began an emergency descent and turned back to Tan Son Nhut.

Unable to maintain flight, at about 4:45 p.m., the Galaxy touched down in a rice paddy two miles short of the runway at 270 knots (500 kilometers per hour). It slid for a quarter mile, became airborne for another half mile, then touched down and slid until it hit a raised dike and broke into four sections. 138 people were killed in the crash.

Although herself seriously injured, Lieutenant Aune began evacuating the children. When rescue helicopters arrived, they were unable to land close to the wrecked transport, so the children had to be carried.

After she had helped to carry about eighty babies, Regina Aune was unable to continue. She asked the first officer she saw to be relieved of her duties and then passed out. At a hospital it was found that she had a broken foot, broken leg and broken vertebra in her back, as well as numerous other injuries.

Regina Aune became the first woman to be awarded the Cheney Award by the Air Force, which was established in 1927 and is awarded “to an airman for an act of valor, extreme fortitude or self-sacrifice in a humanitarian interest, performed in connection with aircraft, but not necessarily of a military nature.“

11 members of the crew of the Galaxy were among the dead, including Captain Mary Therese Klinker, Nurse Corps, United States Air Force.

Mary Therese Klinker was born at Lafayette, Indiana, 3 October 1947. She was the daughter of Paul Edward Klinker and Thelma Mary Deane Klinker. She attended Central Catholic High School in Lafayette, graduating in 1965. She then enrolled at St. Elizabeth’s School of Nursing, also in Lafayette. She graduated as a Registered Nurse, May 1968. On graduation, Miss Klinker worked for St. Elizabeth’s.

Miss Klinker joined the United States Air Force, 9 January 1970, and was commissioned as a lieutenant in the Nurse Corps. She qualified as a flight nurse and was promoted to the rank of captain. In 1974, Captain Klinker was assigned to the 10th Aeromedical Evacuation Squadron, Travis Air Force Base, Fairfield, California.

Captain Mary Therese Klinker, Nurse Corps, United States Air Force, 10th Aeromedical Evacuation Squadron, was the last United States service woman to die in the Vietnam War. Captain Klinker was posthumously awarded the Airman’s Medal and the Meritorious Service Medal. She is buried at St. Boniface Cemetery in her home town of Lafayette, Indiana.

Colonel Regina C. Aune had a very impressive career in the Air Force. She earned a master of Science in Nursing degree, and a Ph.D. She served as Chair of the Department of Nursing Research, Commandant of the Graduate School of Nursing and Deputy Brigade Commander at the Uniformed Services University of the Health Sciences. Aune commanded the 437th Medical Operations Squadron and the 437th Medical Group, Charleston AFB, the 377th Medical Group, Kirtland AFB, the 59th Medical Group, Lackland AFB, and the 386th Expeditionary Medical Group, Kuwait in support of Operation IRAQI FREEDOM. She retired in 2007, and passed away, 27 March 2024.

The pilots, Captain Dennis W. Traynor III and Captain Tilford W. Harp, were both awarded the Air Force Cross for what General Paul Carlton, Commander, Military Airlift Command, called “one of the greatest displays of airmanship I have ever heard related.”

AIR FORCE CROSS

CAPTAIN DENNIS W. TRAYNOR III

Action Date: 3-Apr-75

Service: Air Force

Rank: Captain

Company: 22d Airlift Squadron

Division: Clark Air Base, Philippine Islands

The President of the United States of America, authorized by Title 10, Section 8742, United States Code, takes pleasure in presenting the Air Force Cross to Captain Dennis W. Traynor, III, United States Air Force, for extraordinary heroism and airmanship while engaged in a humanitarian mission as Aircraft Commander of an Air Force C-5A aircraft of the 22d Airlift Squadron, Clark Air Base, Philippine Islands, in action at Saigon, Vietnam on 3 April 1975. On that date, the aircraft, carrying 330 passengers and crew, experienced a serious in-flight emergency which could have resulted in the loss of life for all aboard. With no aircraft controls except one aileron and the engines, Captain Traynor guided the crippled aircraft to a crash landing in a rice paddy, thereby saving the lives of 176 of the people on board. Through his extraordinary heroism, superb airmanship, and aggressiveness, Captain Traynor reflected the highest credit upon himself and the United States Air Force.

AIR FORCE CROSS

CAPTAIN TILFORD W. HARP

Action Date: 3-Apr-75

Service: Air Force

Rank: Captain

Company: 22d Airlift Squadron

Division: Clark Air Base, Philippine Islands

The President of the United States of America, authorized by Title 10, Section 8742, United States Code, takes pleasure in presenting the Air Force Cross to Captain Tilford W. Harp, United States Air Force, for extraordinary heroism and airmanship while engaged in a humanitarian mission as Co-Pilot of an Air Force C-5A aircraft of the 22d Airlift Squadron, Clark Air Base, Philippine Islands, in action at Saigon, Vietnam, on 3 April 1975. On that date, his aircraft, carrying 330 passengers and crew, experienced a serious in-flight emergency which could have resulted in the loss of life for all aboard. With no aircraft controls except one aileron and the engines, Captain Harp provided exceptionally vital assistance to the Aircraft Commander in guiding the crippled aircraft to a crash landing in a rice paddy, thereby saving the lives of 176 of the people on board. Through his extraordinary heroism, superb airmanship, and aggressiveness, Captain Harp reflected the highest credit upon himself and the United States Air Force.

© 2019, Bryan R. Swopes

3 April 1946: The first commercially certified helicopter, Bell Model 47 NC1H, serial number 1, was being flown by two Bell Aircraft Corporation test pilots, Edward F. Hensley and Gerald Arthur (“Jay”) Demming. Hensley was teaching Demming to fly the aircraft.

Demming was hovering the helicopter about 15 feet (4½ meters) above the ground and began to transition to forward flight. Checking the instruments, he noticed that the engine was turning 3,100 r.p.m., the upper limit of its operating range. Intending to reduce the r.p.m., he moved the collective pitch control lever.

When the collective pitch lever is raised (controlled by the helicopter pilot’s left hand), it causes the angle of attack of all main rotor blades to increase, “collectively.” While this increases the amount of lift being produced, it also increases drag, which slows the rotation of both the main rotor and engine. Lowering the collective lever has the opposite effect. Drag is reduced, and the rotor and engine accelerate.

In an early helicopter like the Model 47, the pilot must manually correlate engine r.p.m. with main rotor collective pitch and tail rotor collective pitch. A twist-grip throttle is on the forward end of the collective lever for this purpose. Throttle adjustments are continuous during helicopter flight, as any change in the other controls will effect engine speed.

As Demming was new to the helicopter, he had not yet learned to make these power adjustments automatically. Rather than raise the collective to slow the engine r.p.m., he inadvertently lowered it. This caused a sudden decrease in the rotor blades’ angle of attack and a corresponding decrease in drag. The load on the engine was decreased, but the throttle setting was not reduced accordingly. The engine accelerated to 3,400 r.p.m., which would have driven the main rotor to 378 r.p.m., 5% beyond its maximum operating r.p.m. (“red line”).

Recognizing his error, Demming raised the collective to control the engine/rotor r.p.m.

There was a violent shock. NC1H fell to the ground from a height Demming estimated at 30–50 feet (9–15 meters).

After the impact, both Demming and Hensley were unconscious. Demming soon regained consciousness and got out of the cockpit, while airport fire/rescue personnel looked after Hensley.

Hensley had fractured three vertebra and was initially not expected to survive his injuries, but he did eventually recover.

NC1H, the first civil-certified helicopter, was damaged beyond repair.

In photographs of the damaged helicopter, the main rotor yoke, blade grips, pitch horns, drag braces and the main rotor blades are nowhere to be seen. The gimbal ring, static stop, main rotor retaining nut and stabilizer bar are still in place. This suggests that the hub failed and the associated parts were thrown outward, away from the axis of rotation.

With nothing to support it in flight, the rest of the helicopter dropped to the ground like a stone from your hand.

NC1H (originally registered NX41962) had first flown on 8 December 1945, and had received the very first civil helicopter Type Certificate, H-1, on 8 March 1946.

At the time of the accident, NC1H had 75 hours, 42 minutes, total time (TTAF). Its engine had accumulated 136 hours, 50 minutes, since being manufactured (TTSN).

After the crash, NC1H’s registration number was reassigned to s/n 11.

The Bell 47 series was constructed of a welded tubular steel airframe with a sheet metal cockpit and a characteristic plexiglas bubble canopy. In the original configuration, it had a four-point wheeled landing gear, but this was soon replaced with a tubular skid arrangement. It was a two-place aircraft with dual flight controls.

The first Bell Model 47 had an overall length (with rotors turning) of 39 feet, 7½ inches (12.078 meters). The main rotor diameter was 33 feet, 7 inches (10.236 meters). The length of the fuselage, from the front of the canopy to the trailing edge of the tail rotor disc, was 29 feet, 3½ inches (8.928 meters). The helicopter’s height, to the top of the main rotor mast, was 9 feet, 2–7/16 inches (2.805 meters).

NC1H had an empty weight of 1,393 pounds (632 kilograms). Its gross weight was 2,100 pounds (953 kilograms).

The Bell 47’s main rotor is a two-bladed, under-slung, semi-rigid assembly that would be a characteristic of helicopters built by Bell for decades. The blades were constructed of laminated wood. A stabilizer bar was placed below the hub and linked to the flight controls through hydraulic dampers. This made for a very stable aircraft. The main rotor turns counter-clockwise, as seen from above. (The advancing blade is on the right.) Its normal operating range is 322–360 r.p.m. (294–360 r.p.m. in autorotation).

The tail rotor is positioned on the right side of the tail boom in a tractor configuration. It has a diameter of 5 feet, 5 inches (1.676 meters) and rotates counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the axis of rotation.) The tail rotor blades were also made of wood.

Power was supplied by an air-cooled, normally-aspirated, 333.991-cubic-inch-displacement (5.473 liter) Franklin Engine Company 6V4-178-B3 vertically-opposed six cylinder engine, serial number 17008, which was rated at 178 horsepower at 3,000 r.p.m. Engine torque was sent through a centrifugal clutch to a transmission. The mast (the main rotor drive shaft) was driven through a two-stage planetary gear reduction system with a ratio of 9:1. The transmission also drove the tail rotor drive shaft, and through a vee-belt/pulley system, a large fan to provide cooling air for the engine.

The new helicopter had a cruise speed of 75 miles per hour (121 kilometers per hour) and a maximum speed (V_NE) of 80 miles per hour (129 kilometers per hour). NC1H had a service ceiling of 11,400 feet (3,475 meters).

The Bell 47 was produced at the plant in New York, and later at Fort Worth, Texas. It was steadily improved and remained in production until 1974. In military service the Model 47 was designated H-13 Sioux, (Army and Air Force), HTL (Navy) and HUG (Coast Guard). The helicopter was also built under license by Agusta, Kawasaki and Westland. More than 7,000 were built worldwide and it is believed that about 10% of those remain in service.

In 2010, the type certificates for all Bell 47 models was transferred to Scott’s Helicopter Service, Le Sueur, Minnesota, which continues to manufacture parts and complete helicopters.

Gerald Arthur (“Jay”) Demming was born 4 July 1918 at Niagara Falls, New York. He was the son of Arthur L. Demming, Jr., a factory foreman, and Marie I. Demming. He attended La Salle High School, graduating in 1936, then the University of Illinois at Urbana Champaign.

While at college, Demming entered the Civilian Pilot Training Program. He became a multi-engine and instrument flight instructor at Dominion Skyways Ltd., a flight school at Malton, Ontario, Canada. He was next employed as a civilian pilot for the Royal Canadian Air Force.

On 30 May 1942, Jay Demming married Miss Audrey Mary Prowse. They would have two children. They divorced im May 1966 in Brevard County, Florida.

Gerald Arthur Demming died 20 May 1996, at Plant City, Hillsborough, Florida.

Edward Freeland Hensley was born 22 November 1910 at Mountain Park, Oklahoma. He was the first of three children of Edward Hensley, owner of a real estate company, and Mamie A. Freeland Hensley.  He attended John Brown College at Siloam Springs, Arkansas.

Hensley had brown hair and blue eyes. He was 5 feet, 8 inches tall and weighed 135 pounds.

Hensley married Miss Edith Hyla Collins in Oklahoma City, Oklahoma, 15 August 1931. They would have four children.

In th mid-1930s, Hensley worked for the U.S. Postal Service in Oklahoma City. He was a special deliveries manager.

Hensley was issued a commercial pilot’s license in 1938. By 1940, he was a flight instructor at McConnell Flying Service, Parsons, Kansas. He was next employed as a civilian flight instructor for Brayton Flying Services, inc., at the U.S. Army contract flight school in Cuero Municipal Airport, Cuero, Texas. He then joined Bell Aircraft Corporation as a test pilot.

He later was a test pilot for the Boeing B-47 Stratojet at Wichita, Kansas.

Edward Freeland Hensley died in June 1969 in Wichita.

© 2019, Bryan R. Swopes

2 April 1956: On Monday morning at 8:10 a.m., Pacific Standard Time, Northwest Airlines Flight 2 took off from Seattle-Tacoma Airport en route to New York City, with intermediate stops at Portland, Oregon, and Chicago, Illinois. The airliner, a Boeing 377 Stratocruiser, N74608, had a crew of six and carried 32 passengers. The flight was under the command of Captain Robert Reeve Heard, with First Officer Gene Paul Johnson and Flight Engineer Carl Vernon Thomsen.

The weather at “SeaTac” was overcast, with a ceiling at 1,200 feet (366 meters) and 10 miles (16 kilometers) visibility. The wind was from the east-northeast at 7 knots (3.6 meters per second).

The Boeing reached the cloud layer at 145 knots (167 miles per hour/269 kilometers per hour). The engines were throttled back from takeoff power and the wing flaps were retracted. The airplane suddenly began to buffet severely, as if it were about to stall. (A passenger later said that the airplane “shook like a wet dog.”) It also rolled to the left and Captain Heard had to use full opposite aileron to maintain control. N74608 began to lose altitude.

Captain Heard suspected a split-flap condition, in which, one of the flaps remained partially or fully extended. Initially considering a return to SeaTac, Heard decided that it would be safer to proceed to McChord Air Force Base. The situation continued to worsen. Captain Heard, fearing control would quickly be lost, decided to ditch the Stratocruiser in Puget Sound.

N74608 hit the surface 4.7 nautical miles (5.4 statute miles/8.7 kilometers) from the end of Seattle’s Runway 20, The water was smooth and the airliner coasted to a stop. It then began to take on water. All passengers and crew were evacuated. Two passengers suffered minor injuries. Once in the water, they used seat cushions for flotation. (Flight 2 was not required to carry rafts or life vests.) The water temperature was 42 °F. (5.6 °C.). After about fifteen minutes, the Stratoliner sank in 430 feet (131 meters) of water.

A Northwest Airlines DC-3 flew over the scene and dropped three life rafts. Two U.S. Air Force Grumman SA-16 Albatross amphibians and a U.S. Coast Guard 83-foot (56.6 meters) patrol boat soon arrived on scene. Most of the passengers and crew were rescued. However, four passengers, probably suffering from hypothermia, had drowned. Flight Service Attendant David Victor Razey was missing. The accident occurred on his 27th birthday.¹

The wreck of N74608 was located on the floor of Puget Sound. It was initially moved to shallow water where divers were able to examine it. Later, the airliner was lifted onto a barge.

The Stratoliner’s Number 1 engine (outboard, left wing) was missing and never found. Investigators found that the cowl flaps of the remaining three engines were all fully open. They should have been closed for takeoff.

When the flight crew went through the pre-takeoff check list, in response to the prompt, “Cowl flaps set for takeoff,” the flight engineer responded, “Set for takeoff,” when they were actually open.

At takeoff and climb out speeds, open cowl flaps disrupt the flow of air over the wings. With the wing flaps down, this isn’t noticeable, but when the flaps are retracted, a severe buffeting occurs, as parts of the wing begin to stall.

Investigators found “no failure or malfunction of the aircraft, the power plants, or control systems prior to the ditching.”

Probable Cause:

     The Board determines that the probable cause of the accident was the incorrect analysis of control difficulty which occurred on retraction of the wing flaps as a result of the flight engineer’s failure to close the engine cowl flaps—the analysis having been made under conditions of great urgency and within an extremely short period of time available for decision.

—Civil Aeronautics Board Accident Investigation Report SA-319, File No. 1-0051, 9 November 1956, at Page 8

Northwest Airlines’ N74608 was one of ten Boeing Model 377-10-30 Stratocruisers ordered by the airline. It was built at Seattle, Washington, in 1949, and assigned the manufacturer’s serial number 15954. N74608 carried Northwest’s fleet number, 708. The 377-10-30 was a variant built specifically for Northwest. It can be identified by the rectangular passenger windows.

At the time of the accident, the airliner had flown a total of 18,489 hours (TTAF).

The Model 377 was a large, four-engine civil transport which had been developed, along with the military C-97 Stratofreighter (Boeing Model 367), from the World War II B-29 Superfortress long-range heavy bomber. It utilized the wings and engines of the improved B-50 Superfortress. The airplane was operated by a flight crew of four. It was a double-deck aircraft, with the flight deck, passenger cabin and galley on the upper deck and a lounge and cargo compartments on the lower. The airliner was pressurized and could maintain Sea Level atmospheric pressure while flying at 15,500 feet (4,724 meters). The Model 377 could be configured to carry up to 100 passengers, or 28 in sleeping berths.

The Stratocruiser was 110 feet, 4 inches (33.630 meters) long with a wingspan of 141 feet, 3 inches (43.053 meters) and overall height of 38 feet, 3 inches (11.659 meters). The airliner had an empty weight of 83,500 pounds (37,875 kilograms) and the maximum takeoff weight was 148,000 pounds (67,132 kilograms).

N74608 was powered by four air-cooled, supercharged, 4,362.49-cubic-inch-displacement (71.488 liter) Pratt & Whitney Wasp Major B6 engines. These were four-row, 28-cylinder, radial engines with a compression ratio of 6.7:1.

The B6 had a Normal Power rating of 2,650 horsepower at 2,550 r.p.m., at 5,500 feet (1,676 meters), and Maximum Continuous Power rating of 2,800 horsepower at 2,550 r.p.m. at 3,500 feet (1,067 meters). The Takeoff Power rating was 3,500 horsepower at 2,700 r.p.m. with water/alcohol injection.

The engines drove four-bladed Hamilton Standard Hydromatic 24260 constant-speed propellers with a diameter of 17 feet (5.182 meters) through a 0.375:1 gear reduction.

The Wasp Major B6 was 4 feet, 7.00 inches (1.397 meters) in diameter and 8 feet, 0.50 inches (2.451 meters) long. It weighed 3,584 pounds (1,626 kilograms), dry. The propeller assembly weighed 761 pounds (345 kilograms).

The 377 had a cruise speed of 301 miles per hour (484 kilometers per hour) and a maximum speed of 375 miles per hour (604 kilometers per hour). During testing by Boeing, a 377 reached 409 miles per hour (658 kilometers per hour). Its service ceiling was 32,000 feet (9,754 meters) and the range was 4,200 miles (6,759 kilometers).

Boeing built 56 Model 377 Stratocruisers, with Pan American as the primary user, and another 888 military C-97 Stratofreighter and KC-97 Stratotankers.

¹ David Victor Razey was born 2 April 1929 at Maerdy, Rhondda Cynon Taf, Wales. He had brown hair, hazel eyes and a medium complexion. He was 5 feet, 5 inches (1.65 meters) tall and weighed 140 pounds (63.5 kilograms). Razey became resident of the United States in 1949, and was naturalized as a U.S. citizen, 2 August 1954.

© 2019, Bryan R. Swopes

27 March 1977: The deadliest accident in the history of aviation occurred when two Boeing 747 airliners collided on the runway on the island of Tenerife in the Canary Islands. 583 people died.

A terrorist incident at Gran Canaria International Airport (LPA) on the island of Gran Canaria resulted in the airport being closed for flight operations. This forced many trans-Atlantic airliners to divert to the smaller Los Rodeos Airport (TFN) on Tenerife. The ramp and taxiways at Los Rodeos were congested and refuelers were overwhelmed by the increased traffic, which led to many delays.

Los Rodeos Airport has only one runway, Runway 12/30, with a parallel taxiway and four short taxiways joining the two.

Pan American World Airways’ Flight 1736, a Boeing 747-121, FAA registration number N736PA, named Clipper Victor ¹ was ready for takeoff with 380 passengers and crew, but had to “back taxi” on Runway 12 (“One-Two”) because the parallel taxiway was jammed with airplanes. The airliner proceeded east-southeast, intending to exit the runway to the parallel taxiway after passing by the congestion around the terminal.

Also on the runway was Koninklijke Luchtvaart Maatschappij (KLM) Flight 4805, a Boeing 747-206B, PH-BUF, named Rijn (“Rhine”). The KLM jumbo jet had 248 passengers and crew members on board. Flight 4805 had back-taxied for the entire length of Runway 12, then made a 180° turn to align itself with Runway 30, the “active” runway.

Weather at the time of the accident was IFR, with low clouds and fog. Visibility on the runway was restricted to about 1,000 feet (305 meters). Takeoff rules required a minimum of 2,300 feet (701 meters). What happened next was a misunderstanding between the air traffic controllers and the crew of both airliners.

The control tower instructed KLM 4805 to taxi into position on Runway 30 (“Three-Zero”) for takeoff, and to hold there for release. The Pan Am airliner was told to taxi off the runway and to report when clear. The tower controllers could not see either airliner because of the fog, and their flight crews could not see each other.

The aircraft commander of the Dutch airliner, that company’s Chief Pilot and Chief Flight Instructor, Captain Jacob Veldhuyzen Van Zanten, apparently misunderstood what was occurring and radioed to the tower that he was taking off. He then accelerated.

The crew in the Pan Am airliner heard the KLM pilot report that he was taking off, immediately turned left and ran the engines up to full throttle in order to try to get off the runway. With the KLM 747 accelerating through the fog, its flight crew belatedly realized that the other airliner was still ahead of them. Too late to stop, they applied full power and pulled the nose up trying to takeoff. The tail of their airplane actually dragged over sixty feet (18 meters) on the runway because its extreme nose up angle.

KLM 4805 lifted off about 300 feet (91 meters) from Pan Am 1736, and because of the high angle of attack, its nose wheel actually passed over American airliner’s fuselage, but the rest of the Dutch airplane hit at 140 knots (259 kilometers per hour). Clipper Victor was ripped in half, caught fire and exploded. Rijn crashed about 250 yards (229 meters) down the runway, and it also caught fire and exploded.

All 248 people aboard the Royal Dutch Airlines airplane were killed. Miraculously, there were 61 survivors from the Pan Am Clipper, including the co-pilot, but the remaining 335 died.

The 747-100 series was the first version of the Boeing 747 to be built. It was operated by a flight crew of three and was designed to carry 366 to 452 passengers. It is 231 feet, 10.2 inches (70.668 meters) long with a wingspan of 195 feet, 8 inches (59.639 meters) and overall height of 63 feet, 5 inches (19.329 meters). The interior cabin width is 20 feet (6.096 meters), giving it the name “wide body.” Its empty weight is 370,816 pounds (168,199 kilograms) and the Maximum Takeoff Weight (MTOW) is 735,000 pounds (333,390 kilograms).

The 747-100 is powered by four Pratt & Whitney JT9D-7A high-bypass ratio turbofan engines. The JT9D is a two-spool, axial-flow turbofan engine with a single-stage fan section, 14-stage compressor (11 high- and 3 low-pressure stages) and 6-stage turbine (2 high- and 4 low-pressure stages). The engine is rated at 46,950 pounds of thrust (208.844 kilonewtons), or 48,570 pounds (216.050 kilonewtons) with water injection (2½-minute limit). This engine has a maximum diameter of 7 feet, 11.6 inches (2.428 meters), is 12 feet, 10.2 inches (3.917 meters) long and weighs 8,850 pounds (4,014 kilograms).

The 747-100 has a cruise speed of 0.84 Mach (555 miles per hour, 893 kilometers per hour) at 35,000 feet (10,668 meters). The maximum certificated operating speed is 0.92 Mach. The airliner’s maximum range is 6,100 miles (9,817 kilometers).

The Boeing 747 was in production for 54 years. 1,574 were built. 205 of these were the 747-100 series. The U.S. Air Force has selected the Boeing 747-8i as the next VC-25B presidential transport aircraft.

¹ Pan American World Airways’ Boeing 747 Clipper Victor was the very first Boeing 747 in service. It made its first commercial passenger flight, New York to London, 22 January 1970. Another airliner, Clipper Young America, was scheduled to  make that flight but suffered mechanical problems shortly before departure. Clipper Victor was substituted, but Pan Am changed the airliner’s name to Clipper Young America. On 2 August 1970, N736PA was hijacked to Cuba, and afterwards, to avoid the negative publicity, the name of the 747 was changed back to Clipper Victor.

© 2019, Bryan R. Swopes