Jurassic Technology: The History of the Dyna-Soar

Steven R. Strom

During its brief existence, the nation's first space plane fostered research and technology that influenced space efforts for years to come.

When NASA announced in the spring of 2003 that its next major project would be the design and launch of an orbital space plane, many in the space community sensed that the nation's space program had come full circle. An Air Force program to develop a similar orbiting space plane, the Dyna-Soar, was the first in the nation's history to result in the manufacture of hardware. The Dyna-Soar program was truly a pioneering effort, and although it was canceled in December 1963 without achieving flight, it fostered research that was later applied to the development of the space shuttle and other U.S. space systems.

A largely forgotten aspect of this advanced program is that The Aerospace Corporation, under the direction of the Air Force, was responsible for general systems engineering/technical direction (GSE/TD) for the Dyna-Soar's proposed Titan booster—including modification of Launch Complex 20 at the Atlantic Missile Range. As with other early space programs, Aerospace personnel would ultimately make important contributions to the Dyna-Soar program prior to its cancellation.

Early History

As early as 1951, the Air Force began preliminary conceptual studies for a hypersonic, suborbital boost-glide vehicle (see sidebar, The Suborbital Bomber). Various concepts were proposed throughout the 1950s, ranging from the initial bomber-missile concept to a rocket-bomber to a boost-glide vehicle. By 1957, virtually in tandem with the Soviet launch of Sputnik I, the Air Force had refined and consolidated these competing concepts into a system development plan for the newly named Dyna-Soar (from "dynamic ascent" and "soaring flight"), which was now seen as a follow-up to the experimental X-planes, including, most notably, the X-15. The initial version of Dyna-Soar called for a suborbital hypersonic vehicle that would be launched by a modified Titan I (the country's first two-stage ICBM, first launched in early 1959). Although some early proposals had envisioned the Dyna-Soar as an orbital vehicle, emphasis had shifted to the glider's suborbital capabilities, partly because of the booster's thrust limitations, and partly because of President Eisenhower's belief that the American manned space effort should be directed by a civilian agency. In fact, work on the Dyna-Soar program was to include assistance from the National Advisory Committee for Aeronautics, which later became NASA.

Artist's conception of the Dyna-Soar separating from a Titan booster. (U.S. Air Force)

The Dyna-Soar program was approved in 1958, and in June, contracts were awarded for development of the system, vehicle, and modified Titan booster. The Air Force's Wright Aeronautical Development Center would direct the program, but the Air Force Ballistic Missile Division (AFBMD) would oversee the booster and launch-complex development, with Space Technology Laboratories (STL) assuming the role of GSE/TD for the Titan. Dyna-Soar was designated Program 620A by the Air Force. Disputes over the exact role of Dyna-Soar continued throughout the life of the program, many of which were never resolved. Whether it was a research vehicle, a military space system, or a combination of the two was always a divisive issue within the Department of Defense and even within the Air Force. Despite these differences, many in the Air Force viewed the Dyna-Soar as their best hope for ultimately acquiring a manned presence in space.

A Boost from Aerospace

STL's GSE/TD responsibilities were reassigned to Aerospace following its formation in 1960. The Dyna-Soar program office, part of the Engineering Division, was among the first program offices formed at Aerospace. Under the direction of Walter Tydon, it was divided into four technical departments: Airborne Systems, Ground Systems Equipment, Product Assurance, and Test Planning and Evaluation. Aerospace, as a contractor for AFBMD, was responsible for providing technical direction to AFBMD's associate contractors to ensure the necessary design changes and modifications to the Titan I booster and its ground support equipment, including the launch facilities. Technical direction also extended to the integration of the booster subsystems and the launch complex as well as oversight of the actual launch operations.

The development plan went through numerous changes, and by late 1960, had been divided into three distinct phases. The Aerospace program office was specifically directed to assist with the first phase, research and development of the glider and its associated systems. Airdrops of an unpiloted glider from an airplane were scheduled for mid-1963, and an unpiloted glider launch using the Titan I was planned for late 1963. The final step of phase one included 14 piloted suborbital flights, which were scheduled to begin in early 1964 and conclude in 1966. Phase two involved the actual launching of the Dyna-Soar craft into orbit, while phase three would involve the development of weapons systems that could be used by the Dyna-Soar vehicle. The piloted flights were scheduled to land at four different sites, including one near Fortaleza, Brazil.

At first, Aerospace primarily carried through on decisions previously made by STL. Soon, however, Aerospace began making unique contributions through participation in several important Air Force studies. For example, when the weight of the vehicle increased following the addition of an acceleration rocket, the Air Force asked Aerospace to reevaluate the Dyna-Soar's booster requirements. Following these investigations, Aerospace recommended that the more powerful Titan II be used as the booster. Subsequently, in January 1961, the Air Force announced its decision to switch to a modified Titan II.

Aerospace had also been involved in an Air Force study known as Phoenix, which sought to determine the type of space launching system best suited to meet the needs of future space weapon applications. This study coincided with the new effort to develop a Titan II launch vehicle, and Aerospace Dyna-Soar personnel were able to use the Phoenix study's closely allied knowledge base for their own research.

One of the first studies conducted by the Dyna-Soar team after the adoption of the modified Titan II was an investigation of whether the launch vehicle should use an inertial guidance system, a radio guidance system, or a combination of the two. Ultimately, Aerospace concurred with the contractor that an all-inertial system would be most effective because it freed the missile from any reliance on a ground-based guidance system.

Too Big to Support

The Dyna-Soar program office continued to grow at Aerospace, but by the summer of 1961, there were already indications that it might be phased out before long. To begin with, the increasing weight of the Dyna-Soar was forcing the Air Force to seek an even larger booster. The Soviets, meanwhile, had been launching a series of satellites, each more massive than the previous one. The Vostok I capsule, which carried Yuri Gagarin on his historic orbital flight in April 1961, weighed more than five tons—more than three times the mass of America's Project Mercury capsule. While little was known about the Soviet booster, it was obviously far more powerful than any U.S. rocket. Gagarin's flight was a prominent topic among the Dyna-Soar planners at this time, and many wanted to speed up the Dyna-Soar program by eliminating the suborbital phase altogether, focusing instead entirely on orbital flights. Work at Aerospace was specifically geared toward the suborbital segment, so unless the office received new directives, it would no longer have a viable mission.

When the Dyna-Soar grew too heavy for a standard Titan II, Aerospace recommended the addition of two strap-on solid rocket motors. (U.S. Air Force)

In light of the vehicle's growing weight requirements, the Air Force asked Aerospace to evaluate two competing proposals for a new, more capable Dyna-Soar booster. Aerospace recommended further modifications to the Titan II—specifically, the use of strap-on solid motors for the first stage. This booster was later renamed Titan III, and by the end of October 1961, the Air Force was touting it as the new launch vehicle for Dyna-Soar and for other future military space launches. On October 16, Tydon noted "the strong possibility of the activation of the Titan III program" and pointed out that the expertise earned by members of the Dyna-Soar office "would benefit the Aerospace efforts on Titan III." In November, the Air Force opened a new program office, known as Program 624A, to support the new booster. That same month, Aerospace announced that it was ready to provide GSE/TD to the Titan III development effort.

Once again, the Dyna-Soar program experienced a major revision. In retrospect, one might say that the technology was developing faster than the original schedule, fueled by the intensive space race. Thus, as expected, the Air Force announced in December that all suborbital flights employing the Titan II booster had been eliminated. The developmental program would concentrate on orbital flights using an "improved booster" (i.e., the Titan III). The first piloted flight was projected for August 1965. All flights would last one orbit and land at Edwards Air Force Base. At the urging of Defense Secretary Robert McNamara, the Air Force changed the program's official designation to X-20, highlighting its lineage from the well-known X-15. Nevertheless, the Air Force continued to use the Dyna-Soar name for public references, and both names were used, sometimes interchangeably and sometimes together, for the remainder of the program's life.

Shifting Focus

With the cancellation of suborbital flights, the Aerospace program office found itself without a mandate. By the end of January 1962, Aerospace had reassigned its Dyna-Soar personnel to other offices, primarily the Titan III effort. Although the lifespan of the Aerospace Dyna-Soar program office was relatively brief, Aerospace employees had made a number of contributions toward the effort to develop an adequate booster for the Dyna-Soar vehicle. In addition to its study recommending the Titan II, Aerospace contributions included the solving of difficult telemetry and guidance problems for the Titan II, the introduction of a systems engineering approach in the design of the Dyna-Soar booster configuration, overall system launch planning, development of a system to monitor the Dyna-Soar's malfunction-detection system, studies of the Titan's aerodynamics, and the establishment of reliability criteria for the Dyna-Soar booster system and its subsystems.

Despite the closure of its Dyna-Soar program office, Aerospace continued to support the program indirectly during the final two years of the Dyna-Soar effort. In addition to ongoing assistance from its Program 624A office with the Dyna-Soar booster, Aerospace also had responsibility for developing launchpads 40 and 41 to accommodate the modified Titan III. The Dyna-Soar program itself was coming under increased scrutiny by Defense Secretary McNamara, who was troubled by the program's lack of clear focus and direction. That summer, yet another schedule was released, this time with the addition of multiple-orbit flights.

A model of the Dyna-Soar captured the public's imagination when it was unveiled in 1962. (U.S. Air Force)

Many in the Air Force remained optimistic that the Dyna-Soar could survive in some form, despite McNamara's reservations. When a mockup of Dyna-Soar was rolled out for public inspection in Las Vegas in September 1962, it quickly grabbed the attention of American space enthusiasts. The futuristic look of the space plane supported the optimistic attitude that Americans had toward new technology in the 1960s. By contrast, the blunt-nosed capsule used by the Mercury astronauts looked rather pedestrian. The advanced design of the Dyna-Soar glider is one of the major reasons for its lingering appeal. Writing in Reader's Digest, John G. Hubbell enthusiastically reported that the Dyna-Soar symbolized the best aspects of the American space program. The Dyna-Soar, he wrote, "looks like a cross between a porpoise and a manta ray.... It is a manned space glider—and one of the most important things to have happened in aviation since the Wright Brothers' first flight." During the Las Vegas rollout, the six Air Force pilots selected to fly the Dyna-Soar missions were also presented to the public for the first time.

Dyna-Soar Extinction

Although the Air Force was beginning to make progress on the public relations front, the Dyna-Soar program was coming under greater threat. By the beginning of 1963, the Air Force was under pressure from DOD to provide a better rationale for the program's continued existence. In late January, Secretary McNamara announced a review of the Dyna-Soar, Gemini, and Titan programs to determine which vehicle would best serve the needs of future military space systems. McNamara again raised questions about the program's viability in March during a tour of contractor facilities. In June 1963, engineer Jack H. Irving reported McNamara's growing concerns to the Aerospace Board of Trustees. He pointed out that McNamara was particularly unhappy that "not enough attention has been directed to the specific military missions to be performed." Another program revision was announced in September, but by then it was probably too late to save the Dyna-Soar program, as McNamara had perhaps already made up his mind about its future.

On December 10, 1963, McNamara held a press conference to announce the cancellation of the Dyna-Soar program. At the same time, he revealed that the Dyna-Soar effort would be replaced by the Manned Orbiting Laboratory (which eventually spawned the largest Aerospace program office before it, too, was canceled in 1969).

An Enduring Legacy

Despite its cancellation, the legacy of the Dyna-Soar lives on. For example, many of the space shuttle's design elements and operating capabilities were derived from Dyna-Soar, including its rocket/glider configuration, its ability to land on a runway, its cargo bay, and its reusability. In addition, the extensive wind-tunnel tests conducted for the Dyna-Soar fostered new research methodologies used for several subsequent programs.

Perhaps the program's principal legacy is that in its drive to create a better booster for the Dyna-Soar, the Air Force developed a superior space launch vehicle, the Titan III. According to Ivan Getting, the first president of Aerospace, "Dyna-Soar was a remarkably far-sighted program. Aerospace was on the cutting edge of space research, as it was with the Mercury and Gemini programs." A recently published NASA inventory of American X-vehicles aptly summarizes the primary achievement of the Dyna-Soar program: "Very few vehicles have contributed more to the science of very high-speed flight—especially vehicles that were never built."

Acknowledgment

The author would like to thank Tim Hanrahan for his contribution of information, documents, and photographs for this article.

Works Cited

1. The Aerospace Corporation Archives, Dyna-Soar Collection, AC-066.
2. The Aerospace Corporation Archives, President's Report to the Board of Trustees, Vol. II (all quarterly reports published 1961–1964).
3. Col. J. C. Dieffenderfer, U.S. Air Force, "Current and Possible Future Air Force Space Programs." (Text of address presented in Los Angeles on June 15, 1961.)
4. "Encyclopedia Astronautica," http://www.astronautix.com/craft/dynasoar.htm.
5. Roy F. Houchin II, "Hypersonic Technology and Aerospace Doctrine," Air Power History, Fall 1999, 3–17.
6. J. G. Hubbell, "Here Comes the Dyna-Soar," Reader's Digest, September 1962.
7. Dennis R. Jenkins, Tony Landis, and Jay Miller, American X-Vehicles: An Inventory–X-1 to X-50, Monographs in Aerospace History No. 31 (NASA, Washington, DC, 2003).
8. A. Murray, Man's Role in Dyna-Soar Flight (Boeing Co., Seattle, WA, 1962).
9. Robert F. Piper, History of Titan III, 1961–1963, Vol. I (AFSC Historical Publications Series, 1964).
10. Quest: The History of Spaceflight Magazine, Vol. 3, No. 4 (Winter 1994).
11. Space and Missile Systems Center, Historical Archives, Dyna-Soar File.
12. S. Williams and A. J. Kullas, Dyna Soar Step I: Launch Complex Facility Design Criteria for Dyna Soar (The Martin Company, Seattle, WA, 1962).

To Winter 2004 Table of Contents