Army/RAND World-Circling Spaceship: War is Over, Space Is Just Begun

World-Circling Spaceship

Three views of the World-Circling Spaceship. On the left is the two-stage LOX/LH2 version, while in the centre is the more-developed four-stage LOX/Alcohol version. On the right is a view of the four-stage rocket as it might be assembled on the pad (support vehicle shown, far right). Images from Preliminary Design of a World-Circling Spaceship. Click for a larger version.

What it was: The first attempt to build a ship that could actually reach orbit by an organization that had the wherewithal to do it. Proposed in May 1946, the World Circling Spaceship was in fact two of them: a four-stage Liquid Oxygen/Alcohol rocket whose 500-pound (227-kilogram) upper stage would reach orbit, and an alternative two-stage LOX/Liquid Hydrogen rocket with a similar 500-pound upper stage. While primarily intended for unmanned payloads, putting a man into space with either was considered.

Details: The WWII German rocket team had a design, but no backing. Right after the war, the US Navy could have come up with the funds, but their design (actually several designs) to build a single-stage-to-orbit vehicle would never have worked—SSTO was beyond the technology of the 1940s.

The US Army Air Force, however, could have had both sometime immediately following the spring of 1946. In March they arranged for Douglas Aircraft to put together Project RAND to study intercontinental warfare by means of missiles. Their list of consultants was stellar, and even included Luis Alvarez, later much more famous for his paper proposing an asteroid strike as the cause of the extinction of the dinosaurs, and who would also be on the commission looking into the Challenger disaster.

By May 2, 1946 they had produced the first of what would be a very long line of reports from what would soon be the Rand Corporation. This one was devoted to artificial satellites and was called Preliminary Design of an Experimental World-Circling Spaceship. In it they studied the various issues standing between the present state of the art in rocketry and putting something into orbit, and they came to the conclusion that it could be done with 1946-era engineering. Working backwards from a goal of putting 500 pounds into orbit, they then proceeded to lay out two preliminary designs: a four-stage rocket using liquid oxygen and alcohol for fuel (the same fuels used by the V2 rocket) and an all-cryogenic two-stage rocket using liquid oxygen and liquid hydrogen. They also noted that their initial analysis’ conclusion that a rocket burning LOX/LH2 would be best if it had two stages had turned out to be wrong, and that if time permitted they would have redesigned the second concept to use three stages—not a bad result for 1948, as this prefigures any number of successful three-stage rockets developed since then.

The first actual all-cryogenic three-stage rocket didn’t come about until the Delta IV in the early 21st century, though, as liquid hydrogen is a bit of a bear to handle. In 1946 the knowledge of how to do so simply didn’t exist, so the alcohol fuelled rocket was considered the more conservative choice. As a result the report focused on the four-stage vehicle. Its length was 60 to 70 feet, and its width at its maximum was 12 to 14 feet. Altogether before launch (and including fuel) it would have weighed about 100 tonnes. Promisingly, this makes it quite similar in size to the two-stage Atlas B, a late 1950s rocket which had a payload of 70 kilograms.

A hypothetical launch of one of these rockets would begin on an equatorial Pacific Island, an idea we’d see again a few years later in the Army’s proposal to use Christmas Island as a spaceport for a lunar base. As with that future plan, this was to take advantage of a long downrange area clear of human life as well as getting the maximum possible boost from the Earth’s rotation.

The rocket’s four stages, from largest to smallest and first-firing to last, were charmingly named Grandma, Mother, Daughter, and Baby, with the final one being the orbiting section; in the cryogenic rocket, Baby was perched on one single large stage (unnamed in the report, but call it “The Mother of All Stages” if you like). Each of these stages would have been stripped-down accumulations of fuel and rocket engines with the exception of Baby; it was in charge of guidance for itself and any earlier stage still attached to it and firing, an approach taken by the Proton K/D used for the Soviet circumlunar Zond spacecraft.

Baby’s payload cone would have been 3 feet (0.9 meters) in diameter and 7 feet (2.1 meters) in length, with an internal space of 20 cubic feet (0.57 cubic meters), and the payload’s weight would be no more than 500 pounds. While the assumption was that at first the Baby would be unmanned, a short chapter in the report—almost an aside, not even two full pages long—suggests that this would be big enough for a man and a vivarium to provide him with oxygen. Considering that the cramped Mercury capsule, by far the smallest manned craft ever made, had 60 cubic feet (1.70 cubic meters) of internal space, this was probably optimistic.

Baby’s instrument payload would be swapped in and out to fill a variety of roles. Fundamental research of the near-Earth environment was first, and RAND also pointed out the usefulness of a satellite for geodesy, ultraviolet astronomy, and communications. They even discuss the advantages of a satellite in geostationary orbit, but never actually mention that there’s a considerable difference between 500 pounds to LEO and 500 pounds to 35,786 kilometers up. Probably bearing in mind that RAND was funded by the Army Air Force, they also suggested that Baby could watch the weather over enemy territory, act as a spotter for a nuclear missile in a co-orbit, and send back pictures after an attack to assess its effect. There’s also a surprisingly prescient prediction, eleven years before the Sputnik 1 flap, that Baby would provide value simply by existing, so that it could increase world opinion of the United States.

Though they do mention using television to return images, they considered how best to return Baby to Earth with photographs until such time as radio downlinks were up to the task (and not incidentally so our previously mentioned claustrophilic astronaut could come home). Their solution was to add small wings about 30 square feet in area (2.8 square meters) to the orbiting capsule. This is particularly interesting as it only highlights that Harvey Allen’s discovery that a blunt shape actually reduced re-entry heat with its bow shock—one of the fundamental discoveries of space exploration—was still several years in the future. Lacking that knowledge, RAND suggested that Baby could use its wings to slow the craft’s descent and cut the temperature that way. Both the wings and the capsule’s skin were to be made with stainless steel, which is worrisome in hindsight and appears to be the only place where their analysis missed out on a good understanding of what would be necessary to launch and retrieve an orbital satellite.

RAND suggested that, once given the go-ahead, designing and launching the World-Circling Spaceship would cost US$150 million and take 5 years.

What happened to make it fail: RAND’s report came out at a time when rockets were on the upswing with the Army Air Force (and the independent USAF that followed in 1947). In particular, they were headed by General Carl Spaatz, who was believer in the future role of rocketry in war.

He retired in February of 1948, however, and in October of the same year General Curtis LeMay took over the Strategic Air Command—and they were in charge of any Air Force missiles on American soil. LeMay was of the opposing school to Spaatz, and believed that the future of air war was in bombers. As a result his influence stalled any and all long-range missile projects, let alone one that was as speculative as an orbital launcher in a time of military budget austerity. The World-Circling Spaceship never gained the backing it needed, and soon withered away.

What was necessary for it to succeed: If it had been launched as designed, with stainless steel leading edges on the wings, the first few Babys may have made it into space but weren’t coming home. Apart from that, though, Preliminary Design of an Experimental World-Circling Spaceship is remarkably close to something that could fly considering that it was spec’d out in the Precambrian of the Space Age. With the right personnel (say if Wernher von Braun and his crew had gone along with the Air Force during the divorce from the Army) and someone other than Curtis LeMay in charge of the Strategic Air Command, it’s not hard to see an upgraded Baby beeping its way around the Earth by the end of 1952—a tight schedule, but not out of the question.

Even if they didn’t pull it off by then, after the election of Eisenhower in November of that year it’s an open question if the new president’s preference for civilian control of space exploration would have been enough to stop a project that hadn’t yet put something into orbit but was getting close.

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2 thoughts on “Army/RAND World-Circling Spaceship: War is Over, Space Is Just Begun

  1. I suppose that in theory a stainless-steel wing could be used for re-entry… but it would have to be an extremely slow and painstaking re-entry, more like aerobraking than what we usually understand by the term, and getting it even slightly wrong would be fatal.

    Given how many other things they came up with, I’m faintly surprised they didn’t also invent the de-orbitable film canister used on some of the Key Hole satellites.

    • Douglas Aircraft came up with a trick not long after that might have helped: make the wing’s leading edge out of copper. It conducts the heat away into the rest of the wing and the fuselage and keeps peak temperatures down.

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