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The Cape, Chapter I, Section 4

USAF Space Organizations and Programs

Air Force Space Launch Vehicles: SCOUT, THOR, ATLAS and TITAN

Before we discuss the nation's space launch recovery effort, we need to examine the nature of the Air Force's unmanned launch vehicle programs after 1970 and the direction they were headed in the years preceding the Challenger disaster. For its military missions in the 1970s, the Air Force employed the SCOUT, the THOR, the DELTA, the ATLAS and a family of heavy-lift vehicles based on Martin Marietta's TITAN III standard core booster. The smallest of those vehicles was the SCOUT. The SCOUT was a four- or five-stage solid rocket booster manufactured by the Vought Corporation. The basic four-stage SCOUT (SLV-1A) was approximately 72 feet high and 40 inches in diameter at its widest point. It weighed approximately 38,000 pounds. Depending on the configuration used, the SCOUT developed between 103,000 and 130,000 pounds of thrust, and it was capable of lifting small payloads (e.g., 150 to 400 pounds) into low-Earth orbit. The SCOUT was launched by Vought from Vandenberg Air Force Base, Wallops Island (Virginia) and the San Marcos platform off the coast of Kenya. On 19 April 1977, AFSC signed an agreement that transferred technical direction of Vandenberg's SCOUT launches to NASA. The agreement relieved the 6595th Space Test Group of that responsibility for SCOUT.25

McDonnell Douglas' THOR and DELTA stood on the next step of the launch vehicle hierarchy. The THOR and DELTA were basically liquid-fueled boosters, and they were sometimes equipped with three, six or nine strap-on solid rocket motors to meet various mission requirements. In the 1970s, the basic THOR launch vehicle (configured with a Rocketdyne RS-27 engine) developed approximately 205,000 pounds of thrust at lift-off. The DELTA launch vehicle (which included a THOR booster as its first stage) was between 112 feet and 116 feet high, and it was eight feet in diameter. Though the DELTA's overall dimensions did not increase appreciably from the 1970s into the late 1980s, the vehicle's lift-off weight and power grew considerably. In 1975, a fully loaded DELTA with nine solid rocket motors weighed 291,000 pounds and provided 518,000 pounds of thrust at lift-off. In 1987, the DELTA used to launch the PALAPA B-2P communications satellite weighed approximately 422,000 pounds at lift-off and provided 718,000 pounds of thrust. Though DELTA missions were managed by NASA on both coasts during the 1970s and most of the 1980s, the Air Force supervised THOR missions launched from Space Launch Complex 10 (West) at Vandenberg until THOR space launches there ceased in 1980.26

Figure 22: SCOUT launch
from Vandenberg AFB
19 December 1963

Figure 23: DELTA launch
from Complex 17
October 1975

Figure 24: THOR Launch From SLC-10 (West)
14 July 1980

Slightly below the most powerful DELTAs in lift-off power was General Dynamics' liquid-fueled ATLAS/AGENA. The first stage of the vehicle was the ATLAS Standard Launch Vehicle. It measured 82 feet long and 10 feet in diameter. Like the DELTA, the ATLAS burned RP­1 (highly refined kerosene), and it produced approximately 400,000 pounds of thrust at lift-off. The AGENA second stage was 26 feet long and five feet in diameter. It burned Unsymmetrical Dimethylhydrazine (UDMH) and used Inhibited Red Fuming Nitric Acid as an oxidizer. The AGENA was considerably more powerful than the DELTA upper stage (e.g., 16,100 pounds of thrust versus the DELTA's 9,000 pounds of thrust), and this gave the ATLAS/AGENA an edge over the DELTA in boosting heavier payloads into geosynchronous orbits. The combined weight of the ATLAS/AGENA (minus payload) was approximately 292,000 pounds. As noted earlier, the Test Group's SLV-III Division supported classified ATLAS/AGENA missions from Complex 13 during the 1970s. The last of those missions was launched on 6 April 1978.27

The 6555th Aerospace Test Group phased out its ATLAS/AGENA operations at the Cape in the spring of 1978, but it still maintained technical oversight for Defense Department payloads launched on NASA's ATLAS/CENTAUR boosters from Launch Complex 36. The first of those payloads was launched on 9 February 1978, and seven more military missions were launched from Complex 36 before NASA returned the site to the Air Force in 1990. The first five payloads were boosted into orbit aboard basic ATLAS/CENTAURs, and the remaining spacecraft flew on newer ATLAS G/CENTAURs. The basic ATLAS/CENTAUR was ten feet in diameter. With its payload and fairing in place, it stood 134 feet tall and weighed approximately 326,000 pounds. The ATLAS/CENTAUR's first stage was only 70 feet long, but it generated approximately 431,000 pounds of thrust at lift-off. Like the ATLAS/AGENA, the ATLAS/CENTAUR's first stage burned RP-1 for fuel. The CENTAUR, on the other hand, burned liquid hydrogen. The basic CENTAUR upper stage was 30 feet long, and it delivered approximately 32,800 pounds of thrust. The ATLAS G/CENTAUR was an improved version of the basic launch vehicle. It was 10 feet in diameter, and it stood 137 feet 7 inches high. It weighed approximately 358,000 pounds (minus spacecraft). The ATLAS G first stage was 72.7 feet long, and it generated approximately 437,500 pounds of thrust. The ATLAS G's CENTAUR upper stage produced approximately 33,000 pounds of thrust at altitude.28

Figure 25: Complex 13

Figure 26: ATLAS/CENTAUR launch from Pad 36A
4 May 1979

Figure 27: ATLAS G/CENTAUR launch from Pad 36B
December 1986

Figure 28: TITAN IIIB Space Launch Vehicle

The TITAN IIIB, IIIC and IIID launch vehicles formed the Air Force's family of heavy spacelifters in the 1970s. The "Bs" and "Ds" were launched from Vandenberg Air Force Base, and the "Cs" were launched from the Cape. The TITAN IIIB was the least complicated of the TITAN III operational boosters. It consisted of a TITAN stretched standard core and an AGENA D upper stage. It was used to boost DOD satellites into polar orbits from Vandenberg's Space Launch Complex 4 (West). Nearly five times as powerful as the "B," the TITAN IIID consisted of a standard liquid-fueled core and two solid rocket motors. Each of the solid rocket motors was 85 feet long and 10 feet in diameter. They weighed more than 500,000 pounds apiece and provided a combined thrust of 2,400,000 pounds at lift-off. The TITAN IIID was launched from Space Launch Complex 4 (East), and it boosted heavy payloads (e.g., 24,600 pounds) into low-Earth orbit. In the 1970s, TITAN IIICs were launched only from Launch Complex 40, and they were used to place satellites into very high, geosynchronous equatorial orbits. To accomplish this, the "Cs" were equipped with a standard liquid core, two strap-on solid rocket motors and a liquid-fueled transtage. The TITAN IIIC's core and solid rocket motors were identical to the ones used on the TITAN IIID. The transtage was also ten feet in diameter, but it was 15 feet long. It weighed 28,000 pounds and produced approximately 16,000 pounds of thrust. Depending on the payload fairing that was used, the TITAN IIIC stood between 127 and 150 feet tall.29

Figure 29: TITAN IIID launch from SLC-4 (East)
Vandenberg AFB

Unlike the THOR and ATLAS, the Air Force intended to hold on to its TITAN III class boosters even after the decision had been made to shift many military space operations away from unmanned launch vehicles (and toward the Space Shuttle) by the early 1980s. With that objective in mind, SAMSO began developing a new variant of the TITAN III called the TITAN 34D in June 1976. The TITAN 34D would replace the TITAN IIIC and TITAN IIID, and it would serve as the primary launch vehicle for some military missions and as a backup system for other payloads scheduled for launch aboard the Space Shuttle. Though heavy-lift missions from Vandenberg might only require Titan 34Ds equipped with radio guidance systems, the TITAN 34Ds launched from the Cape would each be equipped with an IUS to meet more complicated flight plans. (Anticipating that requirement, the IUS was developed for both the TITAN 34D and the Space Shuttle to allow greater flexibility and economies of scale.) In September 1978, SAMSO issued a request for proposal for its first three TITAN 34Ds with an option to buy two more in May 1980. The vehicle's specifications called for a slightly longer 110-foot-long Stage I/Stage II core and 90-foot-long solid rocket motors. All booster diameters remained unchanged from the TITAN IIIC/D configuration, but lift-off power improved to 2,800,000 pounds of thrust. Stage I's thrust increased to approximately 530,000 pounds. The Air Force accepted its first three TITAN 34Ds in August 1980. Two more 34Ds were accepted in November and December 1980. The last TITAN IIIC lifted off Complex 40 in March 1982, followed by the first TITAN 34D on 30 October 1982. The last TITAN IIID lifted off Space Launch Complex 4 (East) on 17 November 1982.30

Figure 30: TITAN IIIC launch from Complex 40
14 December 1975

Figure 31: First TITAN 34D launch from the Cape
30 October 1982

The Cape: Miltary Space Operations 1971-1992
by Mark C. Cleary, Chief Historian
45 Space Wing Office of History
1201 Minuteman Ave, Patrick AFB, FL 32925

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