The report identified four “basic mission areas”:
1. Satellite placement, servicing, and recovery. In this mission area, a shuttle would deliver large satellites to low Earth orbit. Such satellites could be checked out in orbit before being deployed, and a future shuttle mission could rendezvous with a satellite “to replace non-operating or outdated” equipment or to return the satellite to Earth for refurbishment.
2. Launch of propulsive stages, propellants and payloads for high energy missions. In this mission area, a shuttle would launch payloads destined for transfer from low Earth orbit to synchronous orbit or other destinations requiring additional propulsion. The shuttle would carry another new system, known as an “orbit-to-orbit shuttle” or “space tug,” to carry out such transfers.
3. Space station/space base logistical support. In this mission area, tied to NASA’s ambitious post-Apollo plans, the space shuttle would serve as a logistics system “capable of routinely transporting numbers of personnel and significant amount of discretionary cargo to and from low earth orbit.” For example, “to sustain operation of a 50-man space base would require on the order of 70,000 pounds of cargo and passengers every three months.” The shuttle could also return to Earth “significant amounts of return cargo such as tapes, film, and processed material.”
4. Short-duration orbital missions. This was the most operationally challenging type of shuttle mission. In purposely opaque language the report noted that the space shuttle could make possible “special purpose orbital missions of a unique nature,” lasting from just one orbit up to seven days, to support “programs of space systems operations, earth sensing or sky viewing.” A shuttle could also place in orbit “self-contained mission modules which possessed their own crews to operate specific mission equipment.” Such modules could either operate from within the shuttle’s payload bay or be left in orbit to be recovered and returned to Earth on a subsequent shuttle flight.
The report noted that “in times of crisis our national leadership requires accurate information for decisions. This information could be crucial to the survival of the United States. The possible locations of crises are worldwide: Southeast Asia, Korea, the Middle East, and Czechoslovakia are but current examples.” In 1969, the only way that national decision makers could get rapid photographic evidence of a situation in a far away crisis area was through an overflight by the U-2 or supersonic SR-71 spy planes, an action that was a violation of national sovereignty and subject to possible interception. The NRO was in 1969 operating a photo-intelligence surveillance satellite called Corona and another, higher resolution satellite called Gambit, but those two systems recorded images on photographic film. That film was returned to Earth in a capsule dropped from orbit and recovered by a waiting aircraft, and it could take from several days to weeks for the final film product to reach the desks of decision makers.10 The DOD/NASA report suggested that a “mission-equipped” shuttle “could return accurate information on a crisis located anywhere in the world or an assessment of an attack to national leaders within the shortest time from launch.” To carry out such a mission, the report discussed “a single-pass [one orbit] request surveillance mission with return to Washington, DC.” That mission would require a cross-range capability of 1,400 nm. Such a space flight would not be a violation of sovereignty according to the practice recognized by the United States and the
Soviet Union since the early 1960s and formalized in the 1967 Outer Space Treaty—that outer space was not subject to national sovereignty. This practice had been interpreted to mean that flying over a particular nation while in outer space was not a violation of its sovereignty.
Another short duration mission possibility mentioned in the report was “the interception and inspection of objects in space.” The report noted that “future unknown satellites could operate for days or weeks, posing a threat ranging from intelligence gathering to delivery of a nuclear weapon,” and suggested that “a national ability to intercept, inspect, and determine the purpose of (as well as destroy, if necessary) unknown satellites is vital.”11
The DOD/NASA report projected a shuttle flight rate between 1975 and 1985 of 30 to 70 flights per year, based on “only those flights required for existing, approved, or high priority planned missions.” Expanding the “mission model” to include flights related to post-Apollo lunar exploration by NASA and other prospective DOD missions could increase the flight rate to 140 missions per year. At such flight rates, the cost of launching a payload to low Earth orbit, the report suggested, could be reduced from approximately $800 per pound to $50-$100 per pound; a similar reduction from $10,000 per pound to less than $500 per pound for payloads going to synchronous orbit was forecast. The report predicted additional cost savings from “major improvements in payload environment, methods of operations, and through return of payload from orbit,” and noted that “the full potential” of a space shuttle “can only be realized if it is indeed a means of low cost transportation.”12
The report concluded that shuttle development “does not require a breakthrough in technology.” Costs of developing the shuttle designs then being considered were estimated to be between $4 and $6 billion. All designs examined had a 15 x 60 foot payload bay and would be able to carry 50,000 pounds to a 100 nm polar orbit (an orbit that would go from south to north, crossing over or near the Earth’s poles) after being launched from California. The vehicle would also be able to return a heavy payload from orbit, allowing satellite refurbishment and re-launch. The 15-foot width of the payload bay was required for “space station logistics support, propulsive stages, and satellites such as. . . surveillance systems.” The 60-foot length of the payload bay was required for “ocean surveillance spacecraft, stage-plus-payloads for synchronous missions, or two medium altitude surveillance satellites.” A cross-range capability of 1,500 nm was “the selected design value.”13
The report concluded by noting that “a fully reusable system has inherent advantages compared to a partially reusable system.” It added that “unless the stage and one-half partially reusable system [an option that at that time was being considered during the NASA Phase A studies and would in 1971 be adopted as the final shuttle design] is found to have substantial advantage in cost, schedule, or reduction in technical risk, a fully reusable system should be selected.”14
The extremely optimistic—indeed, unrealistic—tone of the DOD/NASA report, with its projection of a high space flight rate and the ability to launch on demand and its conclusion that there were no technological barriers to designing a space shuttle that would launch anticipated missions at a major reduction in cost while at the same time offering unique capabilities for new missions, set the baseline for the policy-level discussions of the space shuttle over the next several years. In a period of a few months in early 1969, the shuttle concept had expanded from being only a supply vehicle for a space station, to be launched 8 to 12 times a year, to a system that could launch up to 140 times a year, carrying out all government space missions. This very high launch rate (almost three launches per week!) was well beyond the bounds of realism, but suggests the aspirations of some of those involved in the DOD/ NASA study. The projected low cost of shuttle operations remained a major selling point, and the validity of the report’s call for a large payload bay and substantial cross-range were key issues in the debate over shuttle approval. Thus the June 1969 DOD/NASA report marked a key milestone in the space shuttle decision process.