Tag Archives: Douglas Aircraft Company

22 July 1944

22 July 1944: During an air attack on a Japanese seaplane base and barge landing at Kokas, Enga, Dutch New Guinea, a Douglas A-20G-25-DO Havoc light attack bomber, serial number 43-9432, was hit by anti-aircraft gunfire and crashed into the sea. The pilot, 1st Lieutenant James L. Knarr, on his 70th combat mission, and gunner Staff Sergeant Charles G. Reichley, on his 46th, were killed. The A-20, named Bevo, had been assigned to the 387th Bombardment Squadron, 312th Bombardment Group, based at the Hollandia Airfield Complex.

1. Bevo, a Douglas A-20G Havoc, at the upper right, has been hit by anti-aircraft gunfire and banks right. (U.S. Air Force)
1. Bevo, a Douglas A-20G Havoc, at the upper right, has been hit by anti-aircraft gunfire and banks right, trailing smoke from the open bomb bay. (U.S. Air Force, 53686 A.C.)
2. With the smoke increasing, the A-20 continues to roll right wing down and quickly loses altitude. (U.S. Air Force)
2. With the smoke increasing, the A-20 continues to roll right and quickly loses altitude. (U.S. Air Force, A-53686 A.C.)
3. The attack bomber hits the water and begins to disintegrate. (U.S. Air Force)
3. The attack bomber hits the water and begins to disintegrate. (U.S. Air Force, B-53686 A.C.)
4. Wreckage explodes across the surface of the water. (U.S. Air Force)
4. Wreckage explodes across the surface of Sekar Bay. (U.S. Air Force, C-53686 A.C.)

The Douglas A-20G Havoc was a twin-engine light bomber developed from an earlier export aircraft produced for France and Britain. (In British service, it was known as the Boston. 7,348 A-20s were built at Douglas Aircraft Company plants in Long Beach, El Segundo and Santa Monica, California, from 1939 to 1945. All 2,850 of the A-20G variant were built at Santa Monica from 1943 to 1945.

The A-20G was 48 feet (14.630 meters) long with a wingspan of 61 feet, 4 inches (18.694 meters) and overall height of 17 feet, 7 inches (5.359 meters). It had an empty weight of 17,200 pounds (7,802 kilograms) and maximum takeoff weight of 30,000 pounds (13,608 kilograms).

The A-20G was powered by two air-cooled, supercharged, 2,603.7-cubic-inch-displacement (42.688 liters) Wright Aeronautical Corporation GR2600A5B-0 Cyclone 14 (R-2600-23) two-row, fourteen-cylinder radial engines, each rated at 1,350 horsepower at 2,300 r.p.m., and 1,600 horsepower 2,400 r.p.m., for takeoff. The engines (also commonly called the “Twin Cyclone”) turned three-bladed Hamilton Standard Hydromatic constant-speed propellers with a diameter of 12 feet, 7 inches (3.835 meters) through a 0.5625:1 gear reduction. The R-2600-23 was 4 feet, 10.32 inches (1.481 meters) long, 4 feet, 7.1 inches (1.400 meters) in diameter, and weighed 2,056 pounds (933 kilograms).

The A-20G had a cruise speed of 230 miles per hour (370 kilometers per hour) and maximum speed of 339 miles per hour (546 kilometers per hour) at 12,400 feet (3,780 meters). The service ceiling was 25,800 feet (7,864 meters). Range with a 2,000 pound (907 kilogram) bomb load was 1,025 miles (1,650 kilometers).

The A-20G Havoc was armed with six forward-firing .50-caliber Browning machine guns with 350 rounds of ammunition per gun, a power turret with another two .50-caliber guns and 400 rounds per gun, and a ninth .50 mounted in a ventral tunnel with 400 rounds. The bomber could carry 2,000 pounds (907 kilograms) of bombs in the internal bomb bay and a 500 pounder (227 kilograms) on a hardpoint under each wing.

This Douglas A-20G-45-DO Havoc, 43-22200, at the National Museum of teh United States Air Force, is marked as A-20G-40-DO 43-21475 of the 389th Bombardment Squadron, 312th Bombardment Group. (U.S. Air Force)
This Douglas A-20G-45-DO Havoc, 43-22200, at the National Museum of the United States Air Force, is marked as A-20G-40-DO 43-21475 of the 389th Bombardment Squadron, 312th Bombardment Group. (U.S. Air Force)

© 2016, Bryan R. Swopes

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10 July 1962

Telstar 1 launches aboard a Thor Delta rocket at Launch Complex 17B, 0835 GMT, 10 July 1962. (NASA)
Telstar 1 launches aboard a Delta rocket at Launch Complex 17B, 0835 GMT, 10 July 1962. (NASA)

10 July 1962: At 0835 GMT (4:35 a.m., EDT) the first communications relay satellite, Telstar 1, was launched into orbit from Launch Complex 17B, Cape Canaveral Air Force Station, Florida. The launch vehicle was a three-stage, liquid-fueled, Delta rocket.

This was the first commercial space flight, sponsored by a consortium of communications companies and government organizations, including AT&T, Bell Labs, the BBC, NASA, and British and French postal services. The satellite was used to relay live television broadcasts across the Atlantic Ocean. This had never previously been possible.

Telstar weighed 171 pounds (77.5 kilograms). Its weight and size were restricted by the availability of launch vehicles. It was placed in an elliptical orbit, varying from 591 miles (952 kilometers) to 3,686 miles (5,933 kilometers), and inclined at about a 45° angle to Earth’s Equator. The orbital period was 2 hours, 37 minutes. The properties of Telstar’s orbit restricted its use to about 20 minutes during each pass.

In addition to its primary role as a communications relay satellite, Telstar also performed scientific experiments to study the Van Allen Belt.

The Delta was a three-stage expendable launch vehicle which was developed from the Douglas Aircraft Company’s SM-75 Thor intermediate-range ballistic missile.

Designated Thor DM-19, the first stage was 60.43 feet (18.42 meters) long and 8 feet (2.44 meters) in diameter. Fully fueled, the first stage had a gross weight of 108,770 pounds (49,337 kilograms). It was powered by a Rocketdyne LR-79-7 engine which burned liquid oxygen and RP-1 (a highly-refined kerosene rocket fuel) and produced 170,565 pounds of thrust (758.711 kilonewtons). This stage had a burn time of 2 minutes, 45 seconds.

The second stage was an Aerojet General Corporation-built Delta 104. It was 19 feet, 3 inches (5.88 meters) long with a maximum diameter of 4 feet, 6 inches (1.40 meters). The second stage had a gross weight of 9,859 pounds (4,472 kilograms). It used an Aerojet AJ10-104 rocket engine which burned a hypergolic  mixture of nitric acid and UDMH. The second stage produced 7,890 pounds of thrust (35.096 kilonewtons) and burned for 4 minutes, 38 seconds.

The third stage was an Allegany Ballistics Laboratory Altair 1. It was 6 feet long, 1 foot, 6 inches in diameter and had a gross weight of 524 pounds (238 kilograms). This stage used a solid-fuel Thiokol X-248 rocket engine, producing 2,799 pounds of thrust (12.451 kilonewtons). Its burn time was 4 minutes, 16 seconds.

The three stages of the Delta rocket accelerated the Telstar satellite to 14,688 miles per hour for orbital insertion.

The day prior to launch, the United States detonated a 1.45 megaton thermonuclear warhead at an altitude of 248 miles (400 kilometers), near Johnston Island in the Pacific Ocean. (Operation Dominic-Fishbowl Starfish Prime). Radiation from this test, combined with residual radiation from the Soviet Union’s  57 megaton detonation over Novaya Zemlya Archipelago (RDS-220, known as “Big Ivan,” or “Tsar Bomba”) on 21 October 1961, damaged the satellite’s circuitry and it went out of service in December 1962.

Engineers were able to work around the damage and restore service by January 1963, but Telstar 1 failed permanently 21 February 1963.

Telstar is still in Earth orbit.

Telstar 1 communications relay satellite. (Bell Laboratories)

© 2016, Bryan R. Swopes

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9 July 1962, 09:00:09 UTC, T + 13:41

Fireball of Operation Dominc Starfish Prime, 248 miles ( kilometers) above the Pacific Ocean, 9 July 1962.
Fireball of Operation Dominic-Fishbowl Starfish Prime, 248 miles (399.1 kilometers) above the Pacific Ocean, 9 July 1962.

9 July 1962: At 09:00:09 UTC, the United States detonated a thermonuclear warhead over the Pacific Ocean. This was part of the Operation Dominic-Fishbowl test series at Johnston Island, and was designated Starfish Prime.

At 08:46:28 UTC, a Douglas SM-75 Thor intermediate-range ballistic missile (IRBM) was launched from the Thor missile complex on Johnston Island, carrying a W-49 warhead in an AVCO Corporation Mk-2 reentry vehicle. The Mark 4/W-49 reached a peak altitude of 600 miles (965 kilometers) along a ballistic trajectory then began a descent.

Starfish Prime fireball was visible from Honolulu, Oahu. Hawaii.
Starfish Prime fireball was visible from Honolulu, Oahu, Hawaii, 898 miles (1,445.2 kilometers) from Ground Zero.

The W-49 detonated 36 kilometers (22 miles) southwest of Johnston Island at an altitude of 400 kilometers (246 miles) with an explosive yield of 1.45 megatons. The point of detonation deviated from the planned Air Zero by 1,890 feet (576 meters) to the north, 2,190 feet (668 meters) east, and +617 feet (188 meters) in altitude. The fireball was clearly visible in the Hawaiian Islands, more than 800 miles (1,288 kilometers) away.

The electromagnetic pulse (EMP) damaged electrical systems in The Islands, cutting power, damaging equipment and interrupting telephone systems. Brilliant auroras were visible, lasting about 7 minutes. Telstar, an American communications satellite that was placed in Earth orbit the following day, was also damaged by residual radiation from the detonation.

A Douglas SM-75/PGM-17A Thor IRBM. (U.S. Air Force)
A Douglas SM-75 Thor IRBM. (U.S. Air Force)

The Starfish Prime experiment was for the purpose of, “Evaluation of missile kill mechanisms produced by a high altitude nuclear detonation.” The electromagnetic effects on communications were also studied.

The Douglas Aircraft Company SM-75 Thor (redesignated PGM-17A in 1963) was a single-stage nuclear-armed ballistic missile, 65 feet (19.812 meters) long and 8 feet (2.438 meters) in diameter. It weighed 6,890 pounds (3,125.3 kilograms) empty and 110,000 pounds (49,895.2 kilograms) when fueled.

The SM-75 was powered by one Rocketdyne LR79-NA-9 rocket engine which produced 150,000 pounds of thrust. Two Rocketdyne LR101-NA vernier engines of 1,000 pounds thrust, each, provided directional control and thrust adjustments. The Thor was fueled with kerosene and liquid oxygen sufficient for 165 seconds of engine burn time.

The Thor could reach a maximum speed of 11,020 miles per hour (17,735 kilometers per hour) and had a maximum range of 1,500 miles (2,414 kilometers).

The W-49 thermonuclear warhead was designed by the Los Alamos Scientific Laboratory (LASL) and is believed to be a development of the earlier B-28 two-stage radiation-implosion bomb. It incorporated a 10-kiloton W-34 warhead as a gas-boosted fission primary, and had a one-point-safe safety system. The warhead had a diameter of 1 foot, 8 inches (0.508 meters) and length of  4 feet, 6.3 inches (1.379 meters). It weighed 1,665 pounds (755 kilograms).

The flash from the Starfish-Prime detonation, photographed from Maui in the Hawaiian Islands 15 seconds after detonation. (Los Alamos National Laboratory)
The flash from the Starfish-Prime detonation, photographed from Maui in the Hawaiian Islands, 15 seconds after detonation. (Los Alamos National Laboratory)

© 2016, Bryan R. Swopes

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30 June 1975

The last operational U.S. Air Force C-47 Skytrain, on display at NMUSAF. (U.S. Air Force)
The last operational U.S. Air Force C-47 Skytrain, 43-49507, on display at NMUSAF. (U.S. Air Force)

30 June 1975: The last operational Douglas C-47 Skytrain transport in the United States Air Force, 43-49507, was retired and flown to the National Museum of the United States Air Force at Wright-Patterson Air Force Base, Ohio. A C-47D, it is on display in the World War II Gallery, painted and marked as C-47A-80-DL 43-15213 of the 91st Troop Carrier Squadron, 439th Troop Carrier Group, World War II. At the time it was withdrawn from service, 43-49507 had flown a total of 20,831 hours.

43-49507 (Douglas serial number 26768) was built as a C-47B-15-DK Skytrain. The C-47B differed from the C-47A in that it was powered by Pratt & Whitney Twin Wasp S3C4-G (R-1830-90) engines. These engines were equipped with two-speed superchargers for improved high-altitude performance. Following World War II, the second speed (“high blower”) was either disabled or removed. Following this modification, the airplane was redesignated C-47D.

The Douglas C-47 Skytrain is an all-metal, twin-engine, low-wing monoplane transport with retractable landing gear. It was operated by a minimum flight crew of two pilots, a navigator and a radio operator. The airplane’s control surfaces are covered with doped-fabric. The primary differences between the civil DC-3 and military C-47 airframes was the addition of a cargo door on the left side of the fuselage and a strengthened floor in the cabin.

Two Douglas C-47 Skytrains. Nearest the camera is C-47A-90-DL 43-15661. The further airplane is C-47A-65-DL 42-100550. (U.S. Air Force)

The C-47 is 64 feet, 5½ inches (19.647 meters) long with a wingspan of 95 feet (28.956 meters) and height of 17 feet (5.182 meters). Empty weight of the C-47A is 17,257 pounds (7,828 kilograms) and the maximum takeoff weight is 29,300 pounds (13,290 kilograms).

The C-47A was powered by two 1,829.4-cubic-inch-displacement (29.978 liter) air-cooled, supercharged R-1830-92 (Pratt & Whitney Twin Wasp S1C3-G) two-row 14-cylinder radial engines with a compression ratio of 6.7:1. These were rated at 1,060 horsepower at 2,550 r.pm., up to 7,500 feet (2,286 meters), maximum continuous power, and 1,200 horsepower at 2,700 r.p.m. at Sea Level for takeoff. Each engine drives a three-bladed Hamilton Standard Hydromatic constant-speed full-feathering propeller with a diameter of 11 feet, 6 inches (3.505 meters) through a 16:9 gear reduction. The R-1830-92 is 48.19 inches (1.224 meters) long, 61.67 inches (1.566 meters) in diameter, and weighs 1,465 pounds (665 kilograms).

The specifications of the  Pratt & Whitney Twin Wasp S3C4-G (R-1830-90) installed on the C-47B were nearly the same as the -92 engine of the C-47A. Displacement and compression ratio were identical. The engines’ diameters were the same, though the -90 was very slightly longer than the -92—1.85–2.74 inches (4.699–6.960 centimeters), depending on specific variant. Also, the -90 was heavier than the -92 by 25–30 pounds (11.34–13.61 kilograms), again, depending on the specific variant. The R-1830-90 could maintain 1,000 horsepower at 2,550 r.p.m. at 12,500 feet (3,810 meters), and 1,000 horsepower at 2,700 r.p.m. at 14,000 feet (4,267 meters), a significant increase over the -92.

The C-47 has a cruising speed of 185 miles per hour (298 kilometers per hour) at 10,000 feet (3,048 meters) and service ceiling of 24,100 feet (7,346 meters).

The C-47 could carry 6,000 pounds (2,722 kilograms) of cargo, or 28 fully-equipped paratroopers. Alternatively, 14 patients on stretchers could be carried, along with three attendants.

C-47 Skytrains in Vee-of Vees formation.

On D-Day, The Sixth of June, 1944, a formation of C-47 Skytrains, nine airplanes abreast, 100 feet (30 meters) from wing tip to wing tip, 1,000 feet (305 meters) in trail, stretching for over 300 miles (483 kilometers), airdropped 13,348 paratroopers of the 82nd and 101st Airborne Divisions, United States Army, and another 7,900 men of the British Army 6th Airborne Division and the 1st Canadian Parachute Battalion, behind the beaches at Normandy, France.

During the Vietnam War, 53 C-47s were converted from their transport role to AC-47 Spooky gunships. These were armed with three fixed, electrically-powered General Electric  GAU-2/A .30-caliber (7.62 NATO) Gatling guns firing out the left side of the fuselage. These aircraft were highly effective at providing close air support. The three Miniguns could fire a total of 12,000 rounds per minute.

Douglas AC-47D Spooky gunship, 45-0927, 4th Special Operations Squadron, Nha Trang, Republic of Vietnam, September 1968. (U.S. Air Force)

© 2017, Bryan R. Swopes

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30 June 1956

United Airlines' Douglas DC-7 City of San Francisco, sister ship of Mainliner Vancouver.
United Airlines’ Douglas DC-7 City of San Francisco, N6301C, sister ship of Mainliner Vancouver. (UAL)

30 June 1956: At approximately 10:32 a.m., two airliners, United Airlines’ Douglas DC-7 serial number 44288, Mainliner Vancouver, Civil Aeronautics Administration registration N6324C, and Trans World Airlines’ Lockheed L-1049-54-80 Super Constellation serial number 4016, Star of the Seine, N6902C, were over the Grand Canyon at 21,000 feet (6,400 meters).

Both airliners had departed Los Angeles International Airport shortly after 9:00 a.m. TWA Flight 2 was headed for Kansas City Downtown Airport with 64 passengers and 6 crew members. United Flight 718 was enroute to Chicago Midway Airport with 53 passengers and 5 crewmembers. The airplanes were over the desert southwest, which, at that time, was outside of radar-controlled airspace. They were flying around towering cumulus clouds to comply with regulations that they “remain clear of clouds.”

The airplanes collided at about a 25° angle. The accident report describes the impact:

“First contact involved the center fin leading edge of the Constellation and the left aileron tip of the DC-7. The lower surface of the DC-7 left wing struck the upper aft fuselage of the L-1049 with disintegrating force. The collision ripped open the fuselage of the Constellation from just forward of its tail to near the main cabin door. The empennage of the L-1049 separated almost immediately. The plane pitched down and fell to the ground. Most of the left outer wing of the DC-7 had separated and aileron control was restricted. . . .” 

This illustration depicts the collision. (Milford Joseph Hunter/LIFE Magazine)

It is possible that the DC-7 was maneuvering to avoid the L-1049.  The Constellation struck the ground near Temple Butte at an estimated 475 miles per hour (765 kilometers per hour). The DC-7’s left wing was so badly damaged that it went into an uncontrolled left spin and crashed at Chuar Butte. All persons on both airliners were killed.

This, as well as other accidents, resulted in significant changes in the United States air traffic control system.

A Trans World Airlines Lockheed L-1049 Super Constellation, sister ship of Star of the Seine, photographed over the Grand Canyon. (TWA)

© 2017, Bryan R. Swopes

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