RUSSIA: THE MOONWALK

A special spacesuit was required for the moonwalk. The design requirements for a moonsuit were much tougher than for normal spacewalking, for they required:

• Long duration, so as to make possible a proper programme of lunar surface exploration.

• Spare duration, in the case of difficulty in returning to the LK.

• Tough soles and boots for the lunar surface.

• Durability, so it would not tear if the cosmonaut fell onto the lunar surface.

Russian spacesuits went back to Air Force pressure suits and balloon flights in the 1930s [20]. For the first manned orbital missions, a bright orange pressure suit was developed. The first suit for spacewalking was developed in 1963, called the Berkut. This was used by Alexei Leonov for the first ever spacewalk in March 1965. After this, in anticipation of similar manoeuvres on moon flights, requirements were issued for the testing of a spacesuit suitable for the external transfer between orbiting spacecraft. These refinements were tested by cosmonauts Yevgeni Khrunov and Alexei Yeliseyev in January 1969 and this suit was called the Yastreb. It was the first purely auton­omous spacesuit, without an air supply from the cabin, using a closed-loop life support system. In the course of a 1 hr spacewalk they transferred from Soyuz 5 to Soyuz 4, using a backpack strapped to their legs (the hatches were too wide for the packs to go on their backs).

For the lunar surface spacewalk, a special spacesuit was developed [21]. Chief Designer Vasili Mishin laid down the requirement for a special, semi-rigid spacesuit for the moonwalk, although the contrary view was expressed that it would have been easier to develop a version of the Berkut spacesuit used by Alexei Leonov for Voskhod 2. Design began in 1966. The suit was called Kretchet, though to be more precise Kretchet was the experimental model and Kretchet 94 the final operational version. Responsibility for the spacesuit fell to the Zvezda bureau of Gai Severin, the company which had made the previous suits. The design was finally agreed on 19th March 1968. During this period, the Zvezda bureau also designed and built a traditional soft suit called Oriol, but the higher performing Kretchet appears to have been the favourite all along.

Cosmonaut on the lunar surface

Unlike the American suit, or the earlier Russian suits, which were donned piece by piece, the Russian suit was a semi-rigid, single-piece design that the cosmonaut climbed into through a door at the back. This was a radical departure, making the Kretchet virtually a self-contained spaceship in itself. The idea was not a new one: it had been sketched in detail by Konstantin Tsiolkovsky in 1920 in his science fiction novel Beyond the planet Earth. An important advantage of the suit was its one-size- fits-all approach: cosmonauts inside it were able to adjust its dimensions according to their size. By contrast, the American moonsuits were individually tailored. The Kretchet could be donned – or entered – quickly and it did not take up any more room in the cabin than a traditional suit.

The mission commander first donned the Kretchet in the LOK, before using it to spacewalk over to the LK for the descent to the lunar surface. The Kretchet was designed to work for up to 52 hours, up to six hours at a time and enable the cosmonaut to venture as far as 5 km from the lander. Surface time was estimated at four hours, with 1.5 hours contingency and a half-hour red line emergency (in fact, the designers provided up to ten hours at a time). The suit originally weighed 105 kg on Earth, about a fifth of that on the moon. The moonwalker monitored and controlled the functions of the spacesuit by a fold-down panel console on the front. The suit was designed to be tough, with ten layers of protection.

The Kretchet was designed so that it could be used independently or hooked up to the cabin of the LK and replenished from the LK’s own atmospheric supply. The 52 hr requirement was set down with a view to the suit keeping the cosmonaut alive

Orlan, descendant of the Kretchet

during takeoff and rendezvous should the LK fail to repressurize after the spacewalk. A bizarre feature of the Kretchet was that the designers put around it a kind of hula – hoop ring. The purpose was to ensure that if a cosmonaut fell over, something they worried about, he could use the ring to bounce back up. The Americans had no such system, probably because one astronaut could help his colleague pick himself up if he fell. Later, television viewers saw the later Apollo astronauts fall over many times, doing themselves little evident harm and presenting little danger.

A less rigid version of Kretchet was devised for ordinary spacewalking. This was called Orlan. This followed the same principles but did not carry the hoop, the heavier moonwalk boots nor as large air tanks (2 hr rather than 5 hr). Orlan relied on power supplied from the spaceship, rather than internal systems. It was lighter (59 kg), had only five layers of protection and no waste removal system. This suit would be worn by the flight engineer on board the LOK. In the event of the commander experiencing difficulty going down to the LK or returning therefrom, the flight engineer could venture out in the Orlan to retrieve him.

Twenty-five Kretchet suits were built for testing and training over 1968-71. They were given to the cosmonaut squad for testing. They were put through thermal and vacuum tests in a simulated moon park in the Zagorsk rocket engine test facility. The operation of the suit was checked in a Tupolev 104 aircraft, as were tools for use on the lunar surface. Work on the original Kretchet suit was suspended in 1972 and then, on orders from Valentin Glushko, terminated on 24th June 1974. Nine were in produc­tion at the time. In the course of 1972-4, when work was focused on the N1-L3M programme, the Zvezda design bureau began work on a more advanced version of the Kretchet in the light of the much more ambitious surface expeditions envisaged under the N1-L3M.

Unlike some of the hardware from the lunar landing programme, the Soviet moonsuit story has a happy ending. Kretchet-Orlan was a successful design and subsequently used on the Salyut space stations from 1977 onward and on Mir there­after. A new version, Orlan M, was introduced on the space station Mir and later became the Russian suit used on the International Space Station. It is reckoned to be one of the best spacesuits ever made. The experience gained in developing Oriol was also put to use in the development of the subsequent Sokol Soyuz cabin suit. So almost 40 years later, the successors of the Russian moonsuits are still in good use.

The Russian moon suit, Kretchet

Weight 105 kg

Duration (total) 52 hr

Surface 6 hr+

We know little of what the Soviet cosmonaut would have done on the lunar surface. Our only account comes from I. B. Afanasayev’s monograph Unknown space­craft (1991), one of the early histories of the Soviet moon programme. This is what he says:

The operations on the moon would consist in planting the USSR state flag, deploying the scientific instruments, collection of the lunar soil samples and photographing the terrain, as well as conducting television reportage from the lunar surface. The arsenal ofscientific instruments at the disposal of the Soviet cosmonaut would be extremely restricted by the low weight of cargoes that the LK could carry.

According to Mishin, the lander would have two deployable antennae, two sets of surface experiments and the possibility of a small rover [22]. The best information suggests that the moonwalk would take four hours, not more than 500 m from the cabin, but that the cosmonaut should be able to walk up to 5 km to a reserve LK which, in at least one plan, would be landed nearby. A shorter moonwalk time was also considered, using one of the earlier types of spacesuits (Yastreb), but Mishin held out for a full-length moonwalk using the Kretchet. No decision was taken, but granted that Kretchet was available it seems likely that a full-length moonwalk would have been undertaken.

Collecting the soil sample would have been the first task, as it was on Apollo, so that if the moonwalk had to be aborted, the cosmonaut would at least not return empty-handed. Just as President Nixon made a phone call from the White House to the Apollo 11 astronauts, Leonid Brezhnev would certainly have sent a similar message (he did during the Apollo-Soyuz mission in 1975).

The LK was designed to carry a three-piece surface package. Details are sparse, but they have been assembled by the expert on Soviet space science, Andy Salmon. The main package comprised two seismometers, each with four low-gain aerials, shaped a little like a landmine covered in thermal blankets, to be positioned equi­distant from opposite sides of the LK. As was the case with the American LM, they were carried in the lower stage of the LK and then lifted to their chosen locations by the cosmonaut. The third item was a small crawler or micro-rover, to be deployed at the end of a cable supplying power and communications from the LK. Such a rover, called PrOP-M, was built for Mars missions at this time. Presumably, the rover would be remote-controlled from Earth once the cosmonauts had left the moon and then manoeuvred slowly across the lunar surface. The design has a number of similarities to cabled crawlers carried to the Red Planet by Mars 3 in 1971. Designer of the LK surface package is understood to have been Alexander Gurschikin of the Academy of Sciences.