Almost happened flight to the moon

Rare manned Proton. Almost.

Not all models of manned spacecraft reach a full-fledged flight with the crew. On this one could have finished, but the subsequent fate of such a ship may take shape in different ways. Buran, the Soviet response to the Space Shuttle made only one test flight. And in the eyes of many, he had already surpassed the Shuttle by this flight, having done in unmanned mode what the pilots had always done on the Shuttle. As a result, in his fame, he can argue with some ships on which people successfully flew. Some other ships are almost forgotten and are rarely mentioned outside specialized sites. One of these ships could have greatly influenced the results of the lunar race, but instead fell victim to Soviet secrecy.

At the beginning of the lunar race in the USSR there was no single vision of the flight plan. For flights to the Moon, three different rockets were designed, the oxygen-kerosene super-heavy N-1 and two rockets on the toxic pair NDMG-AT, the heavy R-56 and the super-heavy UR-700. There was also a parallel development of three spacecraft, related to each other orbital 7K-OK (later known as Soyuz) and lunar 7K-LOK, as well as hastily reworked from the Vostok spacecraft multi-seat Rising, the development of which was started for the sake of regular records. Attempting to concentrate efforts on one rocket, the N-1, did not solve all the problems, both because of the increased requirements for carrying capacity from 75 to 90 tons, and because of Sergei Korolev’s conflict with Valentin Glushko, the most experienced designer of rocket engines of the USSR, caused the strongest controversy over the use of toxic fuels.

Since the work on the main lunar rocket H-1 was delayed, in October 1965 it was decided to quickly, using existing missiles, to send a ship (called the 7K-L1 model) to fly around the moon, which would ensure at least an intermediate victory in the lunar race . Three-stage R-7 missiles were not able to send a manned spacecraft to the Moon, so a newly created, already successfully flying Proton was chosen as a launch vehicle, despite the Queen’s reluctance to send people flying a toxic fuel tank. But even this heavy rocket could only send about 5.5 tons to the Moon, which required serious reworking of the taken, still under development, Soyuz spacecraft.


The most notable difference in the 7K-L1 was the rejection of the domestic compartment, which limited the living space to the descent vehicle. Heat protection has been enhanced to ensure safe entry into the atmosphere at a second cosmic velocity. The reserve parachute system and the backup corrective brake propulsion system were removed, a star navigation system and a narrowly targeted communication antenna were added. The on-board digital computer (Argon-11) was used for the first time. The return of the ship meant the original scheme of the two-entry entry into the atmosphere, when at the first entrance the device braked to suborbital speed, flew out of the atmosphere, and then entered it again, already for landing. This allowed the ship to enter the atmosphere from the southern hemisphere, land on the territory of the USSR.

The flights began in the spring of 1967. A total of 15 ships were manufactured, of which two were simplified prototypes designed for testing onboard systems and testing of the upper stage (unit D) of the launch vehicle. According to the original plan, the manned flight was to take place in the summer of the same year, after three successful unmanned tests.

The flight of the first prototype was successful, the spacecraft was put into orbit, after which it was sent to the Moon. Although according to other information, the ship just scored the departure speed, flying not in the direction of the Moon. After recruiting the second cosmic velocity, further work with the device was not planned. The second prototype was also successfully launched into a reference orbit, but the engine of the upper stage did not turn on again, and the ship did not fly to the Moon. After the launch of two prototypes, flights of full-fledged ship versions began, unmanned launches of which formally had to continue the probe probe lineup missions sent to Venus (Zond-1), Mars (Zond-2) and Luna (Zond-3), although technically they did not have nothing in common.

Build Probe

Probe-4 was supposed to fly in a highly elliptical orbit, circling the calculated point at an altitude of 330000km. According to other sources, a flight over the moon was planned, but it was disrupted due to a failure of the orientation system. The first two attempts to send Zond-4 were unsuccessful due to failures in the first and second stages of the launch vehicle. With the third attempt to bring the ship to the desired orbit succeeded. During the flight, problems with the orientation system were found, the sensor constantly lost reference stars, and the first correction of the trajectory could not be carried out. If the subsequent corrections were disrupted, the ship would not be able to return to Earth. The orientation system managed to be adjusted, the trajectory was corrected to ensure normal entry into the atmosphere, but when returning, the descent control system did not work, the ship broke into a ballistic descent into an unpowered area and was undermined by the self-destruction system over Africa.

Probe-5 was also withdrawn from the third attempt. At the first start-up, after a reset of the head fairing a closure occurred in the control system. The second attempt failed even in preparation for the launch, the bursting tank of the oxidizer of the upper stage led to the fall of the ship from the rocket. The third attempt to send the probe was successful, but problems with the stellar orientation system began again. The correction of the trajectory was almost broken, it was necessary to use a less accurate solar-terrestrial orientation. The second correction without a workable stellar orientation was impossible to carry out, which, in turn, made it impossible to control the descent. Fortunately, the probe managed to make a ballistic descent and dive into the Indian Ocean. The ships present there had time to detect the descent module during the flight, and just a few hours later they took it aboard. On the ship, several biological samples were sent to the moon, including two skulls, which became the first living creatures to visit the moon and return to earth.

Probe-6 was successfully launched the first time, departure to the moon was perfect, but then problems started. At first, the rod of a highly directional antenna did not turn, along with the main sensor of the stellar orientation system. The return of the ship was already under question, however, the orientation was carried out with the help of the second stellar sensor, which had never worked successfully before. During the return of the ship, the trouble continued. At first, hydrogen peroxide almost froze, used by orientation engines, which almost made it impossible to perform a controlled descent, and then the ship partially depressurized. The pressure dropped to half the nominal (380mm Hg). Before entering the atmosphere, after separation of the descent vehicle, the depressurization became complete. The equipment not designed for operation in vacuum failed, as a result, the parachute system did not work and the descent vehicle crashed.

Shortly before the launch of Zond-6, NASA announced that in December 1968, the very first manned flight on the Saturn-5 rocket, Apollo-8, would be made to the lunar orbit. This decision was caused by the approach of the Probe program to success, because NASA did not want to allow the Soviet astronaut to be the first person near the Moon. Although the idea to send the next ship to the flight with the crew, before the flight of the Americans, was voiced, but the ship was still not sufficiently developed, and it was not possible to prepare for launch before Apollo. Despite the collective letter sent to the Politburo by the astronauts of the lunar detachment, ready to fly to the Moon even on an unused ship, the manned flight was canceled. However, unmanned launches were continued.

When the Zond-7 was launched for the first time, the rocket could not bring the device into orbit. The following two launches used the N-1 rocket as a carrier and also ended in failure. The fourth launch, accomplished after the return of Apollo 11, was completely successful. The device circled the moon, received color photographs of the Earth and the Moon, and made a controlled descent into the territory of the USSR. In addition to turtles, a FM-2 mannequin, designed for radiological studies, flew to the moon on board the ship, thanks to which Soviet experts were convinced that a flight to the moon outside the time of solar flares did not pose a radiation threat to the crew.

Despite the success of Zond 7 and the possibility of a manned flight, the Soviet leadership decided that after landing on the surface of the moon, such a flight was politically inappropriate. It was decided to send the last unmanned ship and close the program. Probe-8 also made a successful flight, in which an alternative landing pattern was tested - entry into the atmosphere from the northern hemisphere and a single-water landing with a splashdown in the Indian Ocean. This landing scheme was simpler and more reliable than the basic scheme, but excluded the possibility of landing on Soviet territory. Although according to other sources, a similar scheme was caused by a failure of the orientation system, and the descent was ballistic.

Not only Apollo filmed "The Rise of the Earth"

Although the opportunity for a manned flight remained, another manufactured ship remained, but the program was finally closed, and after a few years, after two more N-1 accidents, the entire Soviet manned lunar program was closed. Due to the unwillingness of the Soviet leadership to play the role of a catch-up, the USSR refused even to partial success in flying to the moon. Instead, the policy of denying participation in the lunar race was chosen. The lunar programs were classified, unmanned vehicles were opposed to the Apollo program, and the manned program was concentrated on orbital stations. As a result, NASA astronauts are still the only people who have traveled farther low Earth orbit. It is quite possible, if the probe-9 still flew with people, the resumption of manned flights to the moon would now be perceived more simply and would not scare away excessive ambition.