Orbital Warfare: The Soyuz Space Fighter

Since the retirement of the Space Shuttle, anyone wanting to travel to the International Space Station has to do so in a Russian Soyuz spacecraft. This is an old design, dating back to the 1960s, and many people will be aware that it was a product of the Soviet-American Space Race of the Cold War era. What is less well known, however, is that several military variants of the Soyuz were proposed – including a full-blown space fighter, complete with a nose-mounted 23 mm cannon.

The origins of the Space Race were inextricably linked to military applications from the start. Earth orbit is the perfect place from which to spy on an enemy. As everyone today knows, you can’t hide from a spy satellite. As soon as there were satellites in orbit, both sides – American and Soviet – started to look for ways they could destroy orbiting hardware.

The first successful test of an anti-satellite system took place on October 13, 1959, when a U.S. Air Force Bold Orion missile was launched from a Boeing B-47 Stratojet bomber flying at an altitude of 35,000 feet. The missile successfully intercepted NASA’s Explorer 6 satellite, passing close enough that the satellite would have been destroyed if the missile had been carrying a live warhead.

If an orbiting satellite could be destroyed by an air-launched missile, what about developing space-based weapons as well? This may seem an obvious step, but it isn't as easy as it sounds. Contrary to the impression given by sci-fi movies, maneuvering a vehicle in orbit is completely different from maneuvering inside the Earth’s atmosphere. Intercepting one spacecraft with another is a complex problem in applied physics – and a profoundly counter-intuitive one. During the 1960s, the space programs of both the United States and the Soviet Union were dominated by the need to solve this problem – although it was usually framed as “rendezvous” between two friendly spacecraft, rather than interception of a hostile target.

Early American experiments with space rendezvous used the Gemini spacecraft. This was a civilian program run by NASA, but in December 1963 the USAF announced plans for a military variant code named Gemini B. Based on the same two-man re-entry capsule as the NASA spacecraft, the Air Force variant would also include a cylindrical habitation module accessed through a hatch in the capsule’s heat shield. The project was euphemistically known as the “Manned Orbiting Laboratory” – but of course its real purpose would have been to spy on the Soviet Union.

The Russians responded by announcing a number of military variants of the Soyuz spacecraft, which was then in the early stages of development. The Soyuz R would have been an orbiting reconnaissance platform similar to America’s Manned Orbiting Laboratory. The Soyuz P (P for Perekhvatchik, meaning “interceptor”) had a more proactive role. After rendezvousing with its target – typically an American spy satellite – a cosmonaut would perform a spacewalk to inspect the target, and neutralize it if necessary.

Most dramatic of all, however, was the Soyuz 7K-VI variant. This was designed from the start to carry a gun. Although it never flew, a prototype was constructed – the only publicly acknowledged “space fighter” ever built.

The 7K-VI was given the name Zvezda, meaning “star”. Although it was developed from the basic Soyuz design, it differed significantly in appearance. The usual Soyuz configuration has the rounded cone of the re-entry module in the center, and the roughly spherical orbital module at the front. With Zvezda, the two modules were switched over, and the orbital module had a cylindrical shape. This gave it a “cylinder plus nose cone” appearance more reminiscent of the American Apollo design.

The distinctive solar wings of the Soyuz were dispensed with, too. Instead, the Zvezda obtained its power from a plutonium battery – allowing extended duration missions of up to 30 days in orbit. In order to access the orbital module, a hatch was required in the heat shield of the re-entry module, as in the U.S. Air Force’s Gemini B spacecraft. The presence of the hatch reduced the seating capacity of the spacecraft from three to two.

The 23 mm cannon fitted to the nose of the re-entry module was designed by Aleksandr Nudelman, one of the Soviet Union’s most eminent weapon designers. His space cannon was adapted from one of his aircraft guns. It had to be a strictly recoilless weapon, because any recoil would have altered the orbit of the spacecraft every time the gun was fired.

Plans for the Zvezda space fighter advanced to the point where a crew – Pavel Popovich and Gennadi Kolesnikov – was selected for the first mission. They had already begun training when the program was cancelled in 1967. The Soviets decided to concentrate on an unmanned anti-satellite system, Istrebitel Sputnik, instead (“istrebitel” means fighter and “sputnik” means satellite).

Although Nudelman’s space gun never made it into orbit, the associated firing sight did – it underwent a number of tests on some of the early “civilian” Soyuz flights.