Soyuz 1

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Mission dates
Mission: Soyuz 1
COSPAR-ID : 1967-037A
Spacecraft: Soyuz 7K-OK (A)
( GRAU index  11F615)
serial number 4
Dimensions: 6558 kg
Launcher: Soyuz (GRAY index 11A511)
Call sign: Рубин (" ruby ")
Crew: 1
Begin: April 23, 1967, 12:35:00  UT
Starting place: Baikonur 1/5
Landing: April 24, 1967, 03:22:52 UT
Landing place: 51 ° 22 '  N , 59 ° 34'  E
Flight duration: 1d 2h 47min 52s
Earth orbits: 18th
Rotation time : 88.52 min
Orbit inclination : 51.67 °
Apogee : 224 km
Perigee : 209 km
◄ Before / After ►
Kosmos 140
(unmanned) 		Cosmos 186
(unmanned)
Manned missions:
Vozhod 2 Soyuz 3

Soyuz 1 was the first manned mission to the Soviet spaceship type Soyuz of 23. bis 24. April 1967 . Due to significant technical deficiencies in the energy supply and the attitude control system , the flight was terminated prematurely. The commander Colonel Vladimir Komarov was killed on landing due to a failure of the parachute system.

situation

The Soviet manned space had to 1965, a number of firsts using the 1961 R-7 - launcher and different versions of the Wostok / Woschod spaceship obtained:

  • the first manned space flight: Vostok 1 (April 1961)
  • the first group flight: Vostok 3 and Vostok 4 (August 1962)
  • the first woman in space: Vostok 6 (June 1963)
  • the first multi-seat spaceship: Woschod 1 (October 1964)
  • the first exit into space: Woschod 2 (March 1965)

After that, the Soviet Union lost its leadership role to the USA because the capabilities of the previous launch vehicles and spaceships were exhausted. In contrast to the American Gemini spaceships , the spaceships of the Vostok and Woschod families did not offer any possibility of active orbit change or coupling.

That was supposed to be changed by the newly developed Soyuz spaceship, which had been in development since 1963.

Three consecutive unmanned tests failed.

  • When it was first launched on November 28, 1966, under the code name Kosmos 133 , the spaceship (serial number 2) could not be brought into a stable position in earth orbit. A second spaceship (serial number 1), which should have served as a partner for a rendezvous with Kosmos 133, therefore remained on the ground. The firing of the braking rockets of Kosmos 133 failed several times. When the spaceship finally returned to earth, it threatened to land in China, which should have triggered a self-destruct mechanism. The spaceship was never found, so it was assumed that it exploded as planned.
  • The specimen with the serial number 1 was originally intended to carry out the rendezvous with Kosmos 133 . The start, postponed due to the failure with Kosmos 133 , was supposed to take place on December 14, 1966, but the ignition of some engines failed, so that the start was aborted. During the defuelling, the rescue tower ignited, whereupon the missile was set on fire and exploded shortly afterwards. At least one person was killed.
  • A third spaceship (serial number 3) was launched on February 7, 1967 under the designation Kosmos 140 . However, this spaceship could not be kept stable in orbit either. The re-entry was steeper than planned. The air escaped from the return capsule due to a mistake, and the heat shield burned through. Eventually the capsule crashed into the frozen Aral Sea , where it could be retrieved by divers.
Identical model Soyuz 7K-OK (A) in the National Space Center in England

The American space program had already carried out the first manned rendezvous with Gemini 6 and Gemini 7 a year earlier, in December 1965, but the Apollo program had come to a standstill for the time being after the Apollo 1 disaster in January 1967.

For the Soviets, this meant the opportunity to outdo the rendezvous with a coupling and to showcase the first transfer of space travelers in Earth orbit. Thus, a manned double launch was scheduled for the next two Soyuz spaceships.

crew

Soyuz 1 was piloted by Vladimir Komarov. Komarov had already had space experience with Vozhod 1 . His friend Yuri Gagarin , who six years earlier had been the first person to fly into space, acted as the first substitute .

Flight history and problems encountered

The launch of Soyuz 1 with Vladimir Komarov on board took place on April 23, 1967. Another Soyuz spacecraft ( Soyuz 2A , serial number 5) with a crew of three was to follow the day after. A coupling and the transfer of two cosmonauts were planned. The flight control under the direction of Pavel Agadschanow was in Yevpatoria in the Crimea .

Solar module and sun sensor fail

The first problems arose shortly after reaching the orbit. One of the two solar modules had not unfolded, so the energy supply was not guaranteed. The spaceship could not be aligned stably to the sun, so that the second solar module could not deliver enough power either. This orientation of the spaceship in normal flight operations should take place via a sun sensor that showed a malfunction. Since the Soyuz spaceship only had relatively weak batteries, the intended duration of the mission was not possible. In addition, the shortwave transmitter did not seem to work properly, so that a secure connection was only possible via VHF when the spaceship was over the Soviet Union.

Initially, it was briefly considered that after the originally planned start of Soyuz 2A, the cosmonauts Jelissejew and Chrunow should manually extend the jammed solar module during their outboard transfer, but with the increasing problems of position control, a safe docking maneuver was no longer possible anyway. The start of Soyuz 2A was canceled, officially the bad weather conditions at the launch site were given as the reason.

Automatic position control fails

Three ion flow detectors should supply the correction data for the exact alignment of the spaceship for the braking maneuver. This system measures the deviations of the longitudinal axis of the spaceship from its flight direction in orbit and converts them into appropriate attitude control signals. If the longitudinal alignment is inaccurate, the work of the brake engine cannot guarantee the transition to a safe descent path; the ignition is then automatically suppressed. Using this system, the first attempt was made on the 16th orbit (April 23, 1967; 23:56:12 UT) to detonate the brake rocket and bring Komarov back to earth prematurely. However, the attempt failed because the sensors provided conflicting data. Soyuz 1 remained in orbit. The flight control decided not to carry out any further braking attempts with the automatic system in the next round. Time was of the essence, however, because there were fears that the energy supply would finally fail after circulation 20 or 21.

Manual landing procedure

Instead, the 17th round was intended to prepare for a largely manually controlled landing. The purely optical orientation systems in combination with the gyroscope were probably used for this purpose. Since optical orientation requires daylight and the planned ignition point of the braking maneuver was still on the night side in the 18th orbit, the spaceship was aligned on the opposite side of the earth (e.g. over Papua New Guinea) using optical means and then using the inertial mode stabilized in this position with the signals from the gyroscope. This rather demanding manual maneuver obviously succeeded.

Reentry and crash

After the necessary further half orbit (still in the 18th orbit), Komarow manually ignited the brake engine at 02:57:15 UT shortly after crossing the equator over the Atlantic, which enabled a landing in the USSR in daylight. At about 03:14 UT, shortly before entering the atmosphere, Komarow reported the successful braking maneuver and a positional deviation of more than 8 ° compared to the planned entry angle. As a result, there was no two-part descent, but a purely ballistic one that shifted the landing site to the west. The spaceship entered the radio blackout between 03:15 and 03:16 UT, with the braking deceleration reaching up to 8 g. The main parachute system was activated at a height of about seven kilometers. The auxiliary parachute opened but did not pull the main parachute out of the container. The control systems detected the excessive rate of descent and activated the reserve parachute. This was completely pulled out of its container, but also did not unfold. The Soyuz 1 landing capsule hit hard at 03:22:52 UT about 2 km away from the village of Karabutak ( Orenburg Oblast , then RSFSR , now Russia ) at a speed of about 40 m / s (about 145 km / h) on the ground. Komarov was killed in the process.

Speculation

Komarov only realized that he would not survive the landing when the reserve parachute failed to unfold after the main parachute failed. At that time it was only about 5000 m above sea level and could no longer be received by foreign radio stations via VHF. Hence, occasional reports of screams and curses received in Turkey are referred to the realm of speculation. Nothing was officially disclosed about the actual radio traffic between the end of the blackout and the impact. Officially, there was the last radio contact shortly before the re-entry.

Long after the end of the Soviet Union, a documentary by the television station Perwy kanal dealt with the flight from Soyuz 1 . In addition to a film recording of the impact, the article contains sound recordings that are supposed to be a radio conversation between Vladimir Komarov and Yuri Gagarin as well as the last announcement received from Vladimir Komarov.

Causes of the crash

In the first reports it was stated that the suspension lines of the main parachute twisted and therefore the main parachute would not have fully unfolded. During the investigation, the Soyuz 2A spaceship, which came from the same production lot but was not launched, was also examined intensively. The same design and manufacturing defects were found as with Soyuz 1 . An analysis of the manufacturing process revealed that the binding agent of the ablative heat protection had got into the main shielded container during the curing in an autoclave . This had condensed on its wall and had formed a rough layer. This increased the static friction between the container and the glider. In addition, due to the pressure of the cabin atmosphere compared to the relatively low external atmospheric pressure at a height of approx. 7 km, the parachute container is said to have compressed more than planned after opening. The resulting overall frictional forces prevented the auxiliary parachute from pulling the main parachute out of the container. Under the above-mentioned conditions, a tensile force of approx. 30 kN would have been necessary for this, but the auxiliary parachute reached a maximum of 18 kN and the landing capsule of the first version 7K-OK of the Soyuz spacecraft had a mass of 2.5 t, thus a weight of 25 kN. It was not possible to drop the auxiliary parachute directly. The reserve parachute was deployed, but could not unfold because it fell exactly in the slipstream of the auxiliary parachute of the main parachute system, which was still directly above the landing capsule. Both deficiencies had not occurred in the previous test flight of Kosmos 140 , during which the main screen had unfolded. A different seal for the main umbrella container in the autoclave was used here. In addition, during the re-entry of Kosmos 140, decompression occurred , so that the not inconsiderable pressure difference on the umbrella container was accounted for. These errors in construction (positioning of the reserve parachute, insufficient compression resistance of the main parachute container) and manufacturing (binder contamination) were ultimately the cause of the company's fatal outcome. The entire parachute system was revised for the subsequent flights.

Effects

The Soyuz 1 crash and the death of Komarov were a hard blow to Soviet manned spaceflight. Colonel Komarov was considered one of the most highly qualified active Soviet cosmonauts at the time. For the first time a failure had to be admitted before the world public.

When investigating the accident, several design and manufacturing defects were uncovered. Among other things, the design flaws in the brake screens were discovered. If Soyuz 2A had started as planned, these three cosmonauts would also have died when the main screen was activated. A safe landing with the reserve parachute would only have been possible for both spaceships without prior activation of the main system. It is unclear to what extent such a procedure to rescue the crew would have been recognized and used in good time if Soyuz 2A had taken off. The canceled manned space flight was officially not given a number, but is usually referred to as Soyuz 2A . The originally planned name Soyuz 2 was later used for an unmanned Soyuz spacecraft.

Due to the changes in design and production that had become necessary, the next unmanned launch of Soyuz spaceships with Kosmos 186 and Kosmos 188 was postponed . The next manned launch took place with Soyuz 3 in October 1968, and the planned transfer of cosmonauts was not carried out successfully until January 1969 with Soyuz 4 and Soyuz 5 .

See also

Web links

Individual evidence

  1. ↑ path data for Soyuz 1 mission Transcript, RGANTD, quoted in: Asif Siddiqi: Fifty years later: Soyuz-1 revisited (part 1). The Space Review, April 17, 2017, p. 2 , accessed May 4, 2017 .
  2. ^ Asif Siddiqi: Fifty years later: Soyuz-1 revisited (part 1). The Space Review, April 17, 2017, p. 2 , accessed May 4, 2017 .
  3. ↑ Excerpt from a broadcast by Pervy kanal on Soyuz 1. (Video) Retrieved on September 21, 2015 (Russian).