Tag Archives: Douglas Aircraft Company

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)

© 2018, Bryan R. Swopes

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30 June 1975

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 service with 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, during 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 at Oklahoma City 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.

A group of new Douglas C-47 Skytrains. The airplane closest to the camera is C-47-DL 41-18415. (Douglas Aircraft Company)

The Douglas C-47 Skytrain is a military transport variant of the Douglas Aircraft Company DC-3 commercial airliner. It is an all-metal, twin-engine, low-wing monoplane with retractable landing gear. It was operated by a minimum flight crew of two pilots, navigator, radio operator and mechanic/load master. The airplane’s control surfaces are covered with doped-fabric. The primary differences between the civil DC-3 and military C-47 was the addition of a cargo door on the left side of the fuselage, a strengthened cargo floor, a navigator’s astrodome and provisions for glider towing.

The DC-3 made its first flight 17 December 1935, while the C-47 flew for the first time six years later, 23 December 1941.

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). The total wing area is 988.9 square feet (91.872 square meters). The angle of incidence is 2°. The wing center section is straight, but outboard of the engine nacelles there is 5º dihedral. The wings’ leading edges are swept aft 15.5°. The trailing edges have no sweep.  Empty weight of the C-47D is 17,865 pounds (8,103 kilograms) and the maximum takeoff weight is 33,000 pounds (14,969 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).

U.S. Army paratroopers jump from Douglas C-47-DL Skytrain 41-7805, over England, May 1944. (U.S. Air Force)

The specifications of the  Pratt & Whitney Twin Wasp S3C4-G (R-1830-90) installed on the C-47B and C-47D 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-47D has a cruising speed of 161 knots (185 miles per hour/298 kilometers per hour) at 10,000 feet (3,048 meters), and maximum speed of 202 knots (232 miles per hour/374 kilometers per hour) at 3,500 feet (1,067 meters). Its service ceiling was 22,150 feet (6,751 meters). The Skytrain had a maximum range of 1,026 nautical miles (1,181 miles/1,900 kilometers) with full cargo.

The C-47 could carry 9,485 pounds (4,302 kilograms) of cargo, or 27 fully-equipped paratroopers. Alternatively, 24 patients on stretchers could be carried, along with two 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)

Douglas Aircraft Company built 10,174 C-47 Skytrains at its factories in Santa Monica and Long Beach, California, and at Oklahoma City, Oklahoma.

Douglas DC-3 (C-47B) three-view drawing. (NASA)

© 2018, 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 crew members.

The airplanes were over the United States 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)

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 128 persons on the two 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)

© 2018, Bryan R. Swopes

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17 June 1986

Boeing B-47E-25-DT Stratojet 52-166 is prepared to Depart NAWC China Lake. (U.S. Navy)
B-47E-25-DT Stratojet 52-166 is prepared to depart Armitage Field, NAWS China Lake, 17 June 1986. (U.S.  Air Force)

17 June 1986: After being returned to flyable condition, B-47E-25-DT Stratojet serial number 52-166, made the very last flight of a B-47 when it was flown by Major General John D. (“J.D.”) Moore and Lieutenant Colonel Dale E. Wolfe, U.S. Air Force, from the Naval Air Weapons Station China Lake in the high desert of Southern California, to Castle Air Force Base in California’s San Joaquin Valley, to be placed on static display.

52-166 had been built by the Douglas Aircraft Company at Air Force Plant No. 3, Tulsa, Oklahoma, in 1952. 52-166 had not been flown in twenty years, having sat in the Mojave Desert serving as a radar target. General Moore and Colonel Wolf were experienced B-47 pilots, though they hadn’t flown one in the same twenty years. Because the B-47 it had not been through a complete overhaul prior to the ferry flight, it was decided to leave the landing gear extended to avoid any potential problems.

During the 43 minute trip, the aircraft had several systems fail, including airspeed sensors, intercom, and partial aileron control. On approach to Castle Air Force Base, a 16 foot (4.9 meters) braking parachute was deployed. This created enough aerodynamic drag to slow the airplane while the early turbojet engines were kept operating at high power settings. These engines took a long time to accelerate from idle, making a go-around a very tricky maneuver. With the braking chute, though, releasing the chute allowed the airplane to climb out as the engines were already operating at high r.p.m.

B-47E-25-DT Stratojet 52-166 enroute Castle Air Force Base with a Lockheed T-33A Shooting Star chase. California’s Sierra Nevada Mountains are in the distance. (TSGT Michael Hagerty/U.S. Air Force)
Douglas-built B-47E-25-DT Stratojet 52-166 enroute Castle Air Force Base with a Lockheed T-33A Shooting Star chase, 17 June 1986. California’s Sierra Nevada Mountains are in the distance. (U.S. Air Force)

Designed by Boeing, the Stratojet was a high-subsonic speed strategic bomber and reconnaissance aircraft, in service from 1951 until 1977. The B-47 could fly higher and faster than jet fighters of the time, and it was also highly maneuverable. B-47E (Boeing Model 450-157-35) was flown by a two pilots in a tandem cockpit. A navigator/bombardier was at a station in the nose.

The B-47E Stratojet differed from the earlier B-47B primarily with upgraded engines and strengthened landing gear to handle an increase in maximum weight. The B-47E Stratojet is 107.1 feet (32.644 meters) long with a wingspan of 116.0 feet (35.357 meters), and an overall height of  28.0 feet (8.534 meters). The wings are shoulder-mounted and have a total area of 1,428 square feet (132.67 square meters). The wings’ leading edges are swept aft to 36° 37′. The angle of incidence is 2° 45′ and there is 0° dihdreal (the wings ware very flexible). The B-47E in standard configuration had an empty weight of 78,620 pounds (35,661 kilograms) and maximum takeoff weight of 200,000 pounds (90,718 kilograms).

The B-47E was powered by six General Electric J47-GE-25 turbojet engines in four nacelles mounted on pylons below the wings. This engine has a 12-stage axial-flow compressor, eight combustion chambers, and single-stage turbine. The -25 has a continuous power rating of 5,320 pounds of thrust (23.665 kilonewtons) at 7,630 r.p.m., at Sea Level; Military Power, 5,670 pounds (25.221 kilonewtons) at 7,800 r.p.m. (30 minute limit); and Maximum Power, 7,200 pounds (32.027 kilonewtons) at 7,950 r.p.m. with water/alcohol injection (5 minute limit). The J47-GE-25 has a maximum diameter of 3 feet, 1 inch (0.940 meters) and length of 12 feet, 0 inches (3.658 meters) and weighs 2,653 pounds (1,203 kilograms)

The B-47E had a maximum speed of 497 knots (572 miles per hour/920 kilometers per hour) at 20,000 feet (6,096 meters), and 485 knots (558 miles per hour/898 kilometers per hour) at 38,600 feet (11,765 meters).

The service ceiling was 31,500 feet (9,601 meters) and combat ceiling 40,800 feet (12,436 meters).

The combat radius of the B-47E was 1,780 nautical miles 2,048 miles (3,297 kilometers with a 10,000 pound (4,536 kilograms) bomb load. Ferry range with 14,720 gallons (55,721 liters) of fuel was 4,095 nautical miles (4,712 miles/7,584 kilometers).

For defense the B-47E was armed with two M24A1 20 mm autocannons with 350 rounds of ammunition per gun. The remotely-operated tail turret was controlled by the co-pilot.

The maximum bomb load of the B-47E was 12,000 pounds (5,443 kilograms). The B-47 could carry up to six 2,000 pound (907 kilogram) bombs, or one 10,670 pound (4,840 kilograms) “Special Store”: a B-41 three-stage radiation-implosion thermonuclear bomb with a yield of 25 megatons).

B-47E-25-DT Stratojet 52-166 flies over California's Central Valley farmland as it heads to Castle Air Force Base on the very last B-47 flight, 17 June 1986. (U.S. Air Force)
B-47E-25-DT Stratojet 52-166 flies over California’s Central Valley farmland as it heads to Castle Air Force Base on the very last B-47 flight, 17 June 1986. (U.S. Air Force)

A total of 2,032 B-47s were built by a consortium of aircraft manufacturers: Boeing Airplane Company, Wichita, Kansas; Douglas Aircraft Company, Tulsa, Oklahoma; Lockheed Aircraft Company, Marietta, Georgia.

The Stratojet is one of the most influential aircraft designs of all time and its legacy can be seen in almost every jet airliner built since the 1950s: the swept wing with engines suspended below and ahead on pylons. The B-47 served the United States Air Force from 1951 to 1977. From the first flight of the Boeing XB-47 Stratojet prototype, 17 December 1947, to the final flight of B-47E 52-166, was 38 years, 6 months, 1 day.

B-47E-25-DT Stratojet 52-166 on final approach to land at Castle Air Force Base, 17 June 1986. The braking chute is deployed. This is teh very last time that a B-47 flew.
Douglas-built B-47E-25-DT Stratojet 52-166 on final approach to land at Castle Air Force Base, 17 June 1986. The braking chute is deployed. This was the very last time that a B-47 flew.

© 2018, Bryan R. Swopes

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