16 February 1967

Wilfried von Englehardt tests the Bölkow-Entwicklungen KG Bo-105 V-2, D-HECA in an out-of-ground effect hover, with engine cowlings removed, 16 February 1967. (Eurocopter)
Wilfried von Engelhardt tests the prototype Bölkow-Entwicklungen KG Bo-105 V-2, D-HECA, in an out-of-ground effect hover with engine cowlings removed, 16 February 1967. (Airbus Helicopters Deutschland GmbH)
Wilfried von Englehardt (Académie de l’Air et de l’Espace)
Wilfried von Engelhardt (Académie de l’Air et de l’Espace)

16 February 1967: At Ottobrun, Germany, test pilot Wilfried von Engelhardt made the first flight of the Bölkow-Entwicklungen KG Bo-105 prototype V-2, D-HECA, a twin-engine, rigid rotor helicopter. Baron von Engelhardt took off at 5:04 p.m. The flight lasted 20 minutes. D-HECA was the second prototype. The first one was destroyed by ground resonance during pre-flight testing.

Messerschmitt AG merged with Bölkow-Entwicklungen KG in June 1968, becoming  Messerschmitt-Bölkow. The following year, the new company merged with Blohm & Voss to become Messerschmitt-Bölkow-Blohm KG, or MBB. The Bo-105 A entered production in 1970. A number of civil and military variants followed.

The Bo-105 is a 5-place light helicopter powered by two turboshaft engines. It has a four-bladed rigid (or hingeless) main rotor. This gives it a high degree of maneuverability, and it is capable of performing aerobatic maneuvers. The two-bladed tail rotor is mounted high on a pylon and gives exceptional ground clearance for a helicopter of this size. There are two “clam shell” doors located at the rear of the cabin section, giving access to a large flat floor. The helicopter has been widely used by military, law enforcement and as an air ambulance.

Messerschmitt-Bölkow-Blohm Bo-105 V-2, D-HECA. (Eurocopter)
Bölkow-Entwicklungen KG prototype Bo-105 V-2, D-HECA, during flight testing. (Airbus Helicopters Deutschland GmbH )

The Bo-105 is 11,86 meters (38 feet, 10.9 inches ) long with rotors turning. The fuselage is 8,81 meters (28 feet, 10.9 inches) long, with a maximum width of 1,58 meters (5 feet, 2.2 inches). The helicopter’s overall height is 3.00 meters (9 feet, 10 inches). The helicopter has an empty weight of approximately 1,276 kilograms (2,813 pounds), depending on installed equipment, and maximum takeoff weight of 2,100–2,500 kilograms (5,512 pounds), depending on variant.

The diameter of the main rotor is 9,84 meters (32 feet, 3.4 inches). The main rotor follows the American practice of turning counter-clockwise as seen from above. (The advancing blade is on the right.) It operates at 416–433 r.p.m. (361–467 r.p.m. in autorotation). The tail rotor diameter is 1,90 meters (6 feet, 2.8 inches). It turns clockwise as seen from the helicopter’s left side. (The advancing blade is below the axis of rotation.)

Three-view illustration of the Messerschmitt-Bölkow-Blohm Bo-105 LS (lengthened cabin section). (Nordic Helicopters)

The prototype was powered by two Allison 250-C18 turboshaft engines, with increasingly more powerful 250-C20, -C20B and C-28C engines being added through the production run. The Allison 250-C18 is a 2-spool, reverse-flow, gas turbine engine with a 6-stage axial-flow, 1-stage centrifugal-flow, compressor section, and a 4-stage axial-flow turbine (2-stage gas producer, and 2-stage power turbine). The 250-C18 is rated at 317 shaft horsepower at 51,600 r.p.m., N1 (6,000 r.p.m. N2).

The helicopter’s cruise speed is 127 miles per hour (204 kilometers per hour) and maximum speed (VNE) is 135 knots (155 miles per hour/250 kilometers per hour) at Sea Level. The service ceiling is 17,000 feet (5,180 meters). The Bo-105 C has a maximum fuel capacity of 580.0 liters (153.22 U.S. gallons), of which 570.0 liters (150.58 U.S. gallons) are usable. The range is 691 miles (1,112 kilometers.

The original Type Certificate for the Bölkow Bo-105 A was issued 13 October 1970. Since then, the Bo-105 series has been produced in Germany, Canada, Spain, Indonesia and the Philippines. More than 1,500 were built.

Wilfried von Englehart tests the Bölkow-Entwicklungen KG Bo-105 V-2, D-HECA, at Ottobrun, Germany, 16 February 1967. (Eurocopter)
Wilfried von Engelhardt tests the Bölkow-Entwicklungen KG Bo-105 V-2, D-HECA, at Ottobrun, Germany, 16 February 1967. (Airbus Helicopters Deutschland GmbH)
Charles (“Chuck”) Aaron demonstrates the aerobatic capability of the Messerschmitt-Bölkow-Blohm Bo-105 CBS-4, N154EH. (Red Bull)
Baron von Engelhardt’s parents

Wilhelm Friedrich Franz Eugen Baron von Engelhardt was born at Schloss Liebenberg, north of Berlin, Germany, 11 September 1928. He was the son of the Rudolf Robert Baron von Engelhardt and Ingeborg Maria Alexandrine Mathilde Baroness Engelhardt (Gräfin zu Eulenbrug), and the grandson of Friedrich-Wend Fürst zu Eulenburg-Hertefeld, Count of Sandels.

Wilhelm von Engelhardt had an early interest in aviation.  His stepfather, Generalmajor Carl-August von Schoenebeck, a World War I ace, commanded the Luftwaffe flight test agency at Flugplatz Rechlin-Lärz, Rechlin, Germany. Von Englehardt was able to meet a number of well known German pilots, some of whom were guests at the family home. At the age of 16, he began flight training in gliders.

With the approach of the Soviet Red Army, von Engelhardt and his family fled to Austria. (General Shoenebeck was held as a prisoner of war until 1948.) He trained in hotel management in Salzburg. Following his release from Allied custody, General Schoenebeck formed Luftfahrt-Technik, a distributor for several aircraft manufacturers, including Hiller Helicopters.

With the assistance of General Schoenebeck, in the early 1950s von Engelhardt went to Paris, France, to train as a helicopter mechanic. He next became a helicopter pilot, then flight instructor, in 1958. He flew the Hiller 12, the Bell 47, and the gas turbine-powered Sud-Ouest Djinn. Von Engelhardt flew the SNCASE SE.3130 Alouette II in Papua New Guinea, 1961–1962, then returned to France where he trained as a test pilot at École du personnel navigant d’essais et de réception (EPNER) at Istres.

Von Engelhardt was recommended as test pilot for the Bölkow-Entwicklungen KG Bo-46, by the helicopter’s rotor system designer, Hans Derschmidt. The Bo-46 was an experimental high-speed helicopter. Von Engelhardt made the first liftoff of the prototype aircraft 14 February 1964.

Bölkow-Entwicklungen Bo-46 V-1, D-9514, with the Derschmidt rotor system. (Johan Visschedijk Collection, No. 6705/1000aircraftphotos.com)

Wilhelm von Engelhardt served as Bölkow’s chief test pilot, from 1962 to 1973. He then became the company’s sales director and director of customer service training.

With the Soviet occupation of eastern Germany, the village where Baron von Engelhardt was born was seized. It later came under the jurisdiction of the German Democratic Republic. Following the reunification of East and West Germany, the government of the Federal Republic of Germany held control of Schloss Liebenberg.

Schloss Liebenberg is now a hotel. (Michelin)

In 1996, without informing the local population, the Federal Office for Special Tasks Related to Unification, government’s privatization agency, placed the entire village, including the castle, the 13th century church, all the homes, farm buildings and stable, for sale. The asking price was so high that it was impossible for the villagers to come up with enough money to buy their home town. There was considerable outcry from the villagers, who said that they felt as if they, too, had been put on sale.

Baron von Engelhardt, who was living in a rented coach house on the estate that his family had owned for more than 300 years, gained international recognition for his attempts to negotiate a reasonable outcome.

With his wife, Evamaria, he edited and published Brücke über den Strom, (“Bridge over the Stream”), the letters of his cousin, Sigwart Botho Philipp August zu Eulenburg, Count of Eulenburg, a musical composer who was killed during World War I.

Wilhelm Friedrich Franz Eugen Baron von Engelhardt died 24 January 2015, at the age of 86 years.

Wilfried Baron von Englehardt 1928-2015)
Wilhelm Friedrich Franz Eugen Baron von Engelhardt (11 September 1928–24 January 2015)

© 2019, Bryan R. Swopes

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16 February 1946

The prototype Sikorsky S-51 commercial helicopter, NX19800, in flight between Bridgeport and East Hartford, Connecticut, 1946. (Sikorsky Historical Archive)
The prototype Sikorsky S-51 commercial helicopter, NX92800, in flight between Bridgeport and East Hartford, Connecticut, 1946. (Sikorsky Historical Archive)

16 February 1946: The Sikorsky S-51 prototype, NX92800, made its first flight. The test pilot was Dimitry D. (“Jimmy”) Viner, who later made the first civilian rescue using a helicopter. The S-51 was the first helicopter intended for commercial use, though it was also widely used by military services worldwide. (The prototype was later delivered to Aéronavale, French Naval Aviation.)

Dimitry D. ("Jimmy") Viner with a Sikorsky S-51, the civil version of the R-5. (Sikorsky Historical Archive)
Dimitry D. (“Jimmy”) Viner with a Sikorsky S-51, the civil version of the R-5. (Sikorsky Historical Archive)

The S-51 was a commercial version of the Sikorsky R-5 series military helicopters. It was a four-place, single engine helicopter, operated by one pilot. The cabin was built of aluminum with Plexiglas windows. The fuselage was built of plastic-impregnated plywood, and the tail boom was wood monocoque construction.

The main rotor consisted of three fully-articulated blades built of metal spars and plywood ribs and covered with two layers of fabric. (All metal blades soon became available.) The three bladed semi-articulated tail rotor was built of laminated wood. The main rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right.) The tail rotor was mounted on the helicopter’s left side in a pusher configuration. It turned clockwise as seen from the helicopter’s left. (The advancing blade is below the axis of rotation.)

Sikorsky S-51 three-view illustration with dimensions. (Sikorsky Historical Archives)

The helicopter’s fuselage was 41 feet, 1¾ inches (12.541 meters). The main rotor had a diameter of 48 feet, 0 inches (14.630 meters) and tail rotor diameter was 8 feet, 5 inches (2.568 meters) giving the helicopter an overall length of 57 feet, ½ inch (17.386 meters). It was 12 feet, 11-3/8 inches (3.947 meters) high. The landing gear tread was 12 feet, 0 inches (3.658 meters).

The S-51 had an empty weight of 4,050 pounds (1,837.05 kilograms) and maximum takeoff weight of 5,500 pounds (2,494.76 kilograms). Fuel capacity was 100 gallons (378.5 liters).

Sikorsky S-51 NC92813, Los Angeles Airways, departs on a commercial flight, Los Angeles, California, 1947. (LAT)
Sikorsky S-51 NC92813, Los Angeles Airways, departs on a commercial flight, Los Angeles, California, 1947. (Los Angeles Times)

The helicopter was powered by a 986.749-cubic-inch-displacement (16.170 liter) air-cooled, supercharged, Pratt & Whitney Wasp Jr. T1B4 (R-985 AN-5) direct-drive,  nine-cylinder radial engine which was placed vertically in the fuselage behind the crew compartment. This engine had a compression ratio of 6:1 and was rated at 450 horsepower at 2,300 r.p.m., Standard Day at Sea Level. The R-985 AN-5 was 48.00 inches (1.219 meters) long, 46.25 inches (1.175 meters) in diameter and weighed 684 pounds (310.3 kilograms) with a magnesium crankcase.

The S-51 had a maximum speed (VNE) of 107 knots (123.1 miles per hour/198.2 kilometers per hour). Range was 275 miles (442.6 kilometers). The service ceiling was 14,800 feet (4,511 meters). The absolute hover ceiling was 3,000 feet (914.4 meters).

Of 220 helicopters in the S-51 series built by Sikorsky, 55 were commercial models. Westland built another 159 helicopters under license.

One of Los Angeles Airways' Sikorsky S-51 helicopters takes off from roof of the the Terminal Annex Post Office, Los Angeles, California, 1 October 1947. (Los Angeles Times Photographic Archive/UCLA Library)
One of Los Angeles Airways’ Sikorsky S-51 helicopters takes off from roof of the the Terminal Annex Post Office, Los Angeles, California, 1 October 1947. (Los Angeles Times Photographic Archive/UCLA Library)
Dimitry D. Viner, circa 1931

Дмитро Дмитрович Вінер (Dimitry Dimitry Viner) was born in Kiev, Ukraine, Imperial Russia, 2 October 1908. He was the son of Dimitry Nicholas Weiner and Helen Ivan Sikorsky Weiner, a teacher, and the sister of Igor Ivanovich Sikorsky.

At the age of 15 years, Viner, along with his mother and younger sister, Galina, sailed from Libau, Latvia, aboard the Baltic-American Line passenger steamer S.S. Latvia, arriving at New York City, 23 February 1923.

“Jimmy” Viner quickly went to work for the Sikorsky Aero Engineering Company, founded by his uncle, Igor Sikorsky.

Dimitry Viner became a naturalized United States citizen  on 27 March 1931.

Viner married Miss Irene Regina Burnett. The had a son, Nicholas A. Viner.

On 29 November 1945, Jimmy Viner and Captain Jackson E. Beighle, U.S. Army, flew a Sikorsky YR-5A to rescue two seamen from an oil barge which was breaking up in a storm off of Fairfield, Connecticut. This was the first time that a hoist had been used in an actual rescue at sea.

A Sikorsky R-5 flown by Jimmy Viner with Captain Jack Beighle, lifts a crewman from Texaco Barge No. 397, aground on Penfield Reef, 29 November 1945. (Sikorsky Historical Archive)

In 1947, Viner became the first pilot to log more than 1,000 flight hours in helicopters.

Dimitry Dimitry Viner died at Stratford, Connecticut, 14 June 1998, at the age of 89 years.

© 2019, Bryan R. Swopes

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16 February 1932

Martin XB-907 in flight. (U.S. Air Force)

16 February 1932: First flight, Glenn L. Martin Co. Model 123, designated XB-907 by the U. S. Army Air Corps. It was powered by two Wright Cyclone SR-1820-E engines rated at 600 horsepower, each. The engines were covered by Townend rings to reduce drag and improve cooling.

Martin XB-907

The prototype was tested at Wright Field.  The airplane reached a maximum speed of 197 miles per hour (317 kilometers per hour) at 6,000 feet (1,829 meters). Recommendations for modifications were made, and Martin upgraded the prototype to the XB-907A configuration (Martin Model 139), which was then designated XB-10 by the Air Corps, with the serial number 33-139.

Martin XB-907A, right profile. (U.S. Air Force)

Martin increased the XB-907A’s wingspan from 62 feet, 2 inches (18.948 meters) to 70 feet, 7 inches (21.514 meters). The engines were upgraded to Wright R-1820-19s, rated at 675 horsepower. Full NACA cowlings were installed.

The Army then ordered 48 production airplanes.

The XB-907 would be developed into the Martin B-10 bomber.

U.S. Army Air Corps Martin B-10B of the 28th Bombardment Squadron, Philippine Islands 28 November 1939. (U.S. Air force)

© 2019, Bryan R. Swopes

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15 February 1961, 09:05 UTC

Boeing 707-329 OO-SJB, Sabena Flight 548. (© Guy Van de Merckt)
Boeing 707-329 OO-SJB, Sabena Flight 548. (© Guy Van de Merckt)
Commandant de Bord Ludovic Marie Antoine Lambrechts, Officier de l’Ordre del Couronne, Chevalier de l’Ordre de Leopold. (1917–1961)
Commandant de Bord Ludovic Marie Antoine Lambrechts, Officier de l’Ordre del Couronne, Chevalier de l’Ordre de Leopold. (1917–1961)

15 February 1961, 09:05 UTC: This Boeing 707-329 airliner, registration OO-SJB, under the command of Captain Ludovic Marie Antoine Lambrechts and Captain Jean Roy, was enroute from Idlewild Airport, New York (IDL) to Brussels-Zaventem Airport (BRU) as SABENA Flight SN548, when three miles (4.8 kilometers) short of the runway at an altitude of 900 feet (274 meters), it pulled up, retracted its landing gear and accelerated.

The airliner made three 360° circles, with the angle of bank steadily increasing to 90°. The 707’s wings then leveled, followed by an abrupt pitch up. OO-SJB spiraled into a nose-down dive and crashed into an open field 1.9 miles (3 kilometers) northeast of Brussels and all 61 passengers and 11 crew members and 1 person on the ground were killed, including the entire U.S. Figure Skating Association team, their families, coaches, judges and officials.

Wreckage of Sabena Flight 548, 15 February 1961.
Wreckage of SABENA Flight SN548, Brussels, Belgium, 15 February 1961.

The cause of the crash was never determined but is suspected to be a mechanical failure in the flight control system:

Having carried out all possible reasonable investigations, the Commission concluded that the cause of the accident had to be looked for in the material failure of the flying controls. However, while it was possible to advance certain hypotheses regarding the possible causes, they could not be considered entirely satisfactory. Only the material failure of two systems could lead to a complete explanation, but left the way open to an arbitrary choice because there was not sufficient evidence to corroborate it.”

The Federal Aviation Administration commented that the most plausible hypothesis was a malfunction of the stabilizer adjusting mechanism permitting the stabilizer to run to the 10.5° nose-up position.

Societé Anonyme Belge d’Exploitation de la Navigation Aérienne (SABENA) was the national airline of Belgium. It was based at Brussels and operated from 1923 to 2001.

The United States Figure Skating Association team, boarding SABENA Flight SN548 at Idlewild Airport, New York, 14 February 1961. From left in front row are: Deane McMinn, Laurence Rochon Owen, Steffi Westerfeld and Rhode Lee Michelson. From left on the bottom: Douglas Ramsay, Gregory Kelley, Bradley Lord, Maribel Y. Owen, Dudley Richards, William Hickox, Ray Hadley Jr., Laurie Hickox, Larry Pierce, Ila Ray Hadley, Roger Campbell, Diane Sherbloom, Dona Lee Carrier, and Robert and Patricia Dineen. (U.S.F.S.A.)
The United States Figure Skating Association team, boarding SABENA Flight SN548 at Idlewild Airport, New York, 14 February 1961. From left in front row are: Deane McMinn, Laurence Rochon Owen, Steffi Westerfeld and Rhode Lee Michelson. From left on the bottom: Douglas Ramsay, Gregory Kelley, Bradley Lord, Maribel Y. Owen, Dudley Richards, William Hickox, Ray Hadley Jr., Laurie Hickox, Larry Pierce, Ila Ray Hadley, Roger Campbell, Diane Sherbloom, Dona Lee Carrier, and Robert and Patricia Dineen. (U.S.F.S.A.)
This February 13, 1961 edition of Sports Illustrated was found in the burned-out wreckage of SABENA SN548. U.S.F.S.A. figure skater Laurence Rochon Owen’s photograph is on the cover. The 16-year-old skater is second from the left in the team photograph, above.
This February 13, 1961 edition of Sports Illustrated was found in the burned-out wreckage of SABENA SN548. U.S.F.S.A. figure skater Laurence Rochon Owen’s photograph is on the cover. The 16-year-old skater is second from the left in the team photograph, above.

SABENA Flight SN548 was a Boeing 707-329 Intercontinental. OO-SJB, Boeing serial number 17624, was nearly a new aircraft. It made its first test flight 31 December 1959 at Renton, Washington, and was delivered to SABENA 15 January 1960. At the time of the accident, it had just 3,038 total flight hours (TTAF).

The Boeing 707 was a jet airliner which had been developed from the Model 367–80 prototype, the “Dash Eighty.” It was a four-engine jet transport with swept wings and tail surfaces. The leading edge of the wings were swept at a 35° angle. The airliner had a flight crew of four: pilot, co-pilot, navigator and flight engineer.

The 707-329 Intercontinental is 152 feet, 11 inches (46.611 meters) long with a wing span of 145 feet, 9 inches (44.425 meters). The top of the vertical fin stands 42 feet, 5 inches (12.928 meters) high. The wing is considerably different than on the original 707-120 series, with increased length, different flaps and spoilers, and the engines are mounted further outboard. The vertical fin is taller, the horizontal tail plane has increased span, and there is a ventral fin for improved longitudinal stability.The 707 pre-dated the ”wide-body” airliners, having a fuselage width of 12 feet, 4 inches (3.759 meters).

The airliner’s empty weight is 146,400 pounds (66,406 kilograms). Maximum take off weight (MTOW) is 333,600 pounds (151,320 kilograms). At MTOW, the 707-329 required 10,840 feet (3,280 meters) of runway to take off.

OO-SJB was powered by four Pratt & Whitney JT4A turbojet engines, producing 15,800 pounds of thrust, each. Its maximum speed is 0.80 Mach (552 miles per hour, or 889 kilometers per hour). It had a range of 4,298 miles (6,920 kilometers).

The Boeing 707 was in production from 1958 to 1979. 1,010 were built.

The cover of the 13 February 1961 edition of Sports Illustrated. (SI)
The cover of the 13 February 1961 edition of Sports Illustrated. (SI)

© 2017, Bryan R. Swopes

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15 February 1946

Douglas XC-112A Liftmaster 45-873 (U.S. Air Force)
Douglas XC-112A 45-873 (W. T. Larkins Collection/Wikipedia)

15 February 1946: First flight of Douglas XC-112A (s/n 36326) 45-873.

In 1944, the U.S. Army Air Corps had requested a faster, higher-flying variant of the Douglas C-54E Skymaster, with a pressurized cabin. Douglas Aircraft Company developed the XC-112A in response. It was completed 11 February 1946 and made its first flight 4 days later. With the end of World War II, military requirements were scaled back and no orders for the type were placed.

Douglas saw a need for a new post-war civil airliner to compete with the Lockheed L-049 Constellation. Based on the XC-112A, the prototype Douglas DC-6 was built and made its first flight four months later, 29 June 1946.

Prototype Douglas DC-6 civil transport. (Century of Flight)

The Air Force ordered the twenty-sixth production Douglas DC-6 as a presidential transport, designated VC-118, The Independence. Beginning in 1951, the Air Force ordered a variant of the DC-6A as a the C-118A Liftmaster military transport and MC-118A medical transport. The U.S. Navy ordered it as the R6D-1.

The Douglas DC-6 was flown by a pilot, co-pilot, flight engineer and a navigator on longer flights. It was designed to carry between 48 and 68 passengers, depending on variant.

The DC-6 was 100 feet, 7 inches (30.658 meters) long with a wingspan of 117 feet, 6 inches (35.814 meters) and overall height of 28 feet, 5 inches (8.612 meters). The aircraft had an empty weight of 55,567 pounds (25,205 kilograms) and maximum takeoff weight of 97,200 pounds (44,090 kilograms).

The initial production DC-6 was powered by four 2,804.4-cubic-inch-displacement (45.956 liter), air-cooled, supercharged Pratt & Whitney Double Wasp CA15 two-row, 18 cylinder radial engines with a compression ratio of 6.75:1. The CA15 had a Normal Power rating of 1,800 h.p. at 2,600 r.p.m. at 6,000 feet (1,829 meters), 1,600 horsepower at 16,000 feet (4,877 meters), and 2,400 h.p. at 2,800 r.p.m with water injection for take off. The engines drove  three-bladed Hamilton Standard Hydromatic 43E60 constant-speed propellers with a 15 foot, 2 inch (4.623 meter) diameter through a 0.450:1 gear reduction. The Double Wasp CA15 was 6 feet, 4.39 inches (1.940 meters) long, 4 feet, 4.80 inches (1.341 meters) in diameter, and weighed 2,330 pounds (1,057 kilograms).

The Douglas DC-6 had a cruise speed of 311 miles per hour (501 kilometers per hour) and range of 4,584 miles (7,377 kilometers).

XC-112A 45-873 was redesignated YC-112A and was retained by the Air Force before being transferred to the Civil Aeronautics Administration at Oklahoma City, where it was used as a ground trainer. 36326 was sold at auction as surplus equipment, and was purchased by Conner Airlines, Inc. Miami, Florida and received its first civil registration, N6166G, 1 August 1956. The YC-112A was certified in the transport category, 20 August 1956.

Conner Airlines sold 36326 to Compañia Ecuatoriana de Aviación (CEA), an Ecuadorian airline. Registered HC-ADJ, Ecuatoriana operated 36326 for several years.

It was next re-registered N6166G, 1 August 1962, owned by ASA International. A few months later, 1 May 1963, 36326 was registered to Trabajeros Aereos del Sahara SA (TASSA) a Spanish charter company specializing in the support of oil drilling operations in the Sahara, registered EC-AUC.

XC-112A was operated as a DC-6, EC-AUC, by TASSA Air Charter, seen here at London Gatwick, 29 August 1964. (RuthAS)
The XC-112A was operated as EC-AUC by TASSA Air Charter, seen here at London Gatwick, 29 August 1964. (RuthAS)

In 1965, with a private owner, 36326 was once again re-registered N6166G. Just two weeks after that, 1 June 1965, 36326 was registered to TransAir Canada as CF-TAX.

A TransAir DC-6
A TransAir DC-6

Two years later, 13 June 1967, Mercer Airlines bought 36326. This time the airplane was registered N901MA. Mercer was a charter company which also operated a Douglas C-47 and Douglas DC-4.

N901MA at Hollywood-Burbank Airport (Bureau d'Archives des Accidents d'Avion)
N901MA at Hollywood-Burbank Airport (Bureau d’Archives des Accidents d’Avion)

A Las Vegas, Nevada, hotel chartered Mercer Airlines to fly a group of passengers from Ontario International Airport (ONT), Ontario, California, to McCarran International Airport (LAS). On 8 February 1976, 36326, operating as Mercer Flight 901, was preparing to fly from Hollywood-Burbank Airport (BUR) where it was based, to ONT. The airliner had a flight crew of three: Captain James R. Seccombe, First Officer Jack R. Finger,  Flight Engineer Arthur M. Bankers. There were two flight attendants in the passenger cabin, along with another Mercer employee.

Weather at BUR was reported as 1,000 feet (305 meters) scattered, 7,000 feet (2,134 meters) overcast, with visibility 4 miles (6.4 kilometers) in light rain and fog. The air temperature was 56 °F. (13.3  °C.), the wind was 180° at 4 knots (2 meters per second).

At 10:35 a.m. PST (18:35 UTC), Flight 901 was cleared for a rolling takeoff on Burbank’s Runway 15. While on takeoff roll, Flight Engineer Bankers observed a warning light for engine #3 (inboard, starboard wing). He called out a warning to the Captain, however, the takeoff continued.

Immediately after takeoff, a propeller blade on #3 failed. The intense vibration from the unbalanced propeller tore the #3 engine off of the airplane’s wing, and it fell on to the runway below.

The thrown blade passed through the lower fuselage, cut through hydraulic and pneumatic lines and electrical cables and then struck the #2 engine (inboard, port wing), further damaging the airplane’s electrical components and putting a large hole in that engine’s forward accessory drive case. The engine rapidly lost lubricating oil.

Flight 901 declared an emergency and requested to land on Runway 07, which was approved by the Burbank control tower, though they were informed that debris from the engine was on the runway at the intersection of 15/33 and 07/25. The airplane circled to the right to line up for Runway 07.

Just prior to touchdown, warning lights indicated that the propeller on the #2 engine had reversed. (In fact, it had not.) Captain Seccombe announced that they would only reverse #1 and #4 (the outboard engines, port and starboard wings) to slow 36326 after landing, and the airplane touched down very close to the approach end of the runway.

Because of the damage to the airplane’s systems, the outboard propellers would not reverse to slow the airplane and the service and emergency brakes also had failed. N901MA was in danger of running off the east end of the 6,055 foot (1,846 meters) runway, across the busy Hollywood Way and on into the city beyond.

The flight crew applied full power on the remaining three engines and again took off.  The landing gear would not retract. The electrical systems failed. The #2 engine lost oil pressure and began to slow.

The DC-6 circled to the right again and headed toward Van Nuys Airport (VNY), 6.9 miles (11.1 kilometers) west of Hollywood-Burbank Airport. They informed Burbank tower that they would be landing on Van Nuys Runway 34L which was 8,000 feet (2,438 meters) long. Because of the emergency, the crew remained on Burbank’s radio frequency. The #2 engine then stopped but the propeller could not be feathered.

Bob Hope Burbank irport is at the right edge of this image, and Van Nuys Airport is at the left. Woodly Golf Course is just south of VNY. (Google Earth image)
Hollywood-Burbank Airport (BUR) is at the right edge of this image, and Van Nuys Airport is at the left. Woodley Lakes Golf Course is just south of VNY. (Google Earth image)

Van Nuys weather was reported as 600 feet (183 meters) scattered, 10,000 feet (3,048 meters) overcast, with visibility 10 miles (16.1 kilometers) in light rain, temperature 55 °F. (12.8 °C.). The airliner was flying in and out of the clouds and the crew was on instruments. [1045: “Special, 1,200 scattered, 10,000 feet overcast, visibility—10 miles, rainshowers, wind—130° at 4 kn, altimeter setting—29.93 in.”]

Because of the drag of the unfeathered engine #2 propeller and the extended landing gear, the Flight 901 was unable to maintain altitude with the two remaining engines. The airplane was not able to reach the runway at VNY.

A forced landing was made on a golf course just south of the airport. The airplane touched down about 1 mile south of the threshold of Runway 34L on the main landing gear and bounced three times. At 10:44:55, the nose then struck the foundation of a partially constructed building, crushing the cockpit. All three flight crew members were killed by the impact.

N901MA-2
Douglas YC-112A serial number 36326, N901MA, shortly after crash landing at Woodley Golf Course, Van Nuys, California, 8 February 1976. (Bureau d’Archives des Accidents d’Avions)

Both flight attendants were trapped under their damaged seats but were able to free themselves. They and the passenger were able to escape from the wreck with minor injuries.

Los Angeles City Fire Department firefighters attempted to rescue the crew by cutting into the fuselage. Even though the area around the airplane had been covered with fire-retardant foam, at about 20 minutes after the crash, sparks from the power saw ignited gasoline fumes. Fire erupted around the airplane. Ten firefighters were burned, three severely. N901MA was destroyed.

"Feb. 8, 1976: Firemen scatter after saw ignites gas fumes at crash site of DC-6 in Van Nuys. Three trapped crew members of Mercer Enterprises DC-6 charter plane died. Ten firemen were injured." (Boris Yaro/Los Angeles Times)
“Feb. 8, 1976: Firemen scatter after saw ignites gas fumes at crash site of DC-6 in Van Nuys. Three trapped crew members of Mercer Enterprises DC-6 charter plane died. Ten firemen were injured.” (Boris Yaro/Los Angeles Times)

At the time of the accident, YC-112A 36326 was just three days short of the 30th anniversary of its completion at Douglas. It had flown a total of 10,280.4 hours. It was powered by three Pratt & Whitney R-2800-83 AMS, and one R-2800-CA18 Double Wasp engines. All four engines drove three-bladed Curtiss-Wright Type C632-S constant-speed propellers. The failed propeller had been overhauled then installed on N901MA 85 hours prior to the 8 February flight.

The National Transportation Safety Board investigated the accident. It was found that a fatigue fracture in the leading edge of the propeller blade had caused the failure. Though the propeller had recently been overhauled, it was discovered that the most recent procedures had not been followed. This required that the rubber deicing boots be stripped so that a magnetic inspection could be made of the blade’s entire surface. Because this had not been done, the crack in the hollow steel blade was not found.

© 2019, Bryan R. Swopes

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