Military Review

Aviation spacesuits SI-1 and SI-3M: the first independent developments of "Zvezda"

The first completely independent development of the plant No. 918 (JSC "NPP" Zvezda ") was the model of the high-altitude spacesuit" SI-1 ", and a few years later the improved model" SI-3M ". Earlier VSS series - VSS-04A, VSS-04M, VSS-05, VS-06, VSS-07 (VKS-1) (1953–1954), not to mention E.E. Chertovsky (Ch-1, Ch-3), were created on the basis of VSS spacesuits developed at LII, and with all the differences in individual elements, they had basically the same design scheme.

Aviation spacesuits SI-1 and SI-3M: the first independent developments of "Zvezda"

General information about SI-1 and SI-3M spacesuits

aviation SI-1 and SI-3M spacesuits were developed in the mid-50s. (1955 and 1956 respectively) of the last century and belonged to the "ventilation type", when the air and oxygen entering the spacesuit are removed from it through the pressure regulator. This ventilation system is called open and is typical for aviation and rescue space suits.

The second feature of the SI-1 and SI-3M spacesuits was the presence of an oxygen mask. This type of spacesuit is called "mask".

In mask-type spacesuits, an oxygen-air mixture (or pure oxygen) for breathing was supplied through an oxygen mask, and the spacesuit was ventilated with air from the aircraft pressurization system.

The SI-1 and SI-3M spacesuits had a pressurized shell, which simultaneously performs the functions of a power and hermetic shell. As a rule, the casing was made of two or three layers of rubberized cotton fabric (percale).

When flying in a pressurized cockpit, the suits had an overpressure of about 10–20 hPa (100–200 mm of water column), which made it possible to unfold their shell and “remove” the weight of the suit from the pilot's body, providing him with internal space for movement. When the cabin was depressurized at altitudes of more than 10–11 km, an operating excess pressure of the order of 150–220 hPa was created in the spacesuit, which was sufficient for breathing pure oxygen and at the same time ensured acceptable mobility. The maximum flight altitude in a spacesuit was about 20 km.

On November 1, 1962, test parachutists P.I. Dolgov and E.N. Andreev in SI-3M spacesuits ascended in the Volga stratospheric balloon to a height of 25,5 kilometers and made a parachute jump. For this jump, the SI-3M spacesuit was modified. The oxygen mask and oxygen device were removed from it, and oxygen was supplied to the helmet in a continuous stream (a maskless type of spacesuit, which later became widespread).

At the moment of exiting the gondola for a parachute jump, P.I. Dolgov straightened up and hit the protruding object of the hatch with his helmet. The blow was so strong that the glass of the helmet was broken, and the spacesuit was depressurized, which led to the death of P.I. Dolgov.

E.N. Andreev landed safely.

This tragedy led to the following modifications to the suits being either double glazed or the spherical helmet was replaced with a helmet with a metal helmet. Unfortunately, many technical solutions and safety rules in aviation are written in blood. And don't forget about that.

SI-1 or SI-3M spacesuits: similar and different

On SI-3M, the most effective solution was introduced to eliminate the inevitable "spacesuit growth".

On the SI-1, a power system was used using a wide transverse belt with a slit in the back, which was connected through a system of rollers to the longitudinal power cords of the body (the so-called pulley power system). When the suit was inflated, the belt had to move apart, while choosing the length of the longitudinal cords. However (due to the high friction between the belt and the shell), the system proved to be ineffective in eliminating “overgrowth” and was used only for adjusting spacesuits in height.

For the first time, the SI-3M used the so-called front pull-up - adjustable with a special power band buckle connecting the neck ring with the inguinal zone of the sheath.

The second difference between SI-1 and SI-3M is the location of the group communication input: SI-1 has it on the left side, while SI-3M has it on the right.

These suits have not gained much popularity.

However, they became an important stage in the development of design ideas and were an integral part of the Soviet approach to the creation of aviation and space equipment.
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  1. Vladimir_2U
    Vladimir_2U 29 December 2020 12: 13
    An interesting article, in the Internet there are not very many materials about the spacesuits of the USSR.
    1. Alien From
      Alien From 29 December 2020 12: 54
      One hundred percent agree with you, a very interesting and little-covered topic!
    2. The leader of the Redskins
      The leader of the Redskins 29 December 2020 13: 10
      Definitely a plus. Not pouring from empty to empty, but a new, little disclosed topic. Very important for VO, lately.
    3. merkava-2bet
      merkava-2bet 29 December 2020 18: 44
      And not only in spacesuits, last week I was looking for scuba gear and normobaric sea spacesuits, so to speak, a historical excursion, gulkin's nose, mostly foreign, sorry.
      1. Bshkaus
        29 December 2020 22: 35
        very interesting and little-covered topic!

        I'm glad I liked it, I'll get out of the "New Year's drinking", I'll tell you about the "Vorkuta" spacesuit)))) Then about the aviation "Falcon", smoothly moving on to how it became space, and then to the "Orlan" through the lunar "Gyrfalcon" a stone's throw))))
        1. Vladimir_2U
          Vladimir_2U 30 December 2020 03: 13
          We wait! Happy New Year!
  2. JonnyT
    JonnyT 29 December 2020 14: 24
    Thanks, very interesting.
  3. dgonni
    dgonni 29 December 2020 14: 33
    Here is a look at Soviet spacesuits and the feeling that they were made in a circle does not leave skillful hands from what they got and blinded. Look at the shtatovskie of the same years. Well, straight sweetie. Later Soviet ones already shoved amers into both sexes.
    1. ycuce234-san
      ycuce234-san 30 December 2020 07: 14
      Then the materials were like rubberized percale, which now give the impression of "old school". And now, despite the new materials, they seem to have stalled in development - for example, no one is developing for military aviators all-metal space suits or body armor space suits with ceramic and Kevlar anti-fragmentation protection, space suits with human protection from fire, spacesuits integrated into a capsule chair and other new items.
      The skafs never arrived on civilian aircraft - although, in the event of an accident, explosion, depressurization, attack, fires, it is extremely important that the crew is capable and able to land the plane - and there is no progress here. Liners fall to themselves, and to force them to develop protection for their pilots - and it never occurs to anyone ...
      1. Bshkaus
        30 December 2020 09: 10
        no one develops for military aviators all-metal space suits or body armor space suits with ceramic and kevlar anti-fragmentation protection, space suits with protection of a person from fire, space suits integrated into a capsule chair and other novelties.

        See, in order:
        1 integrating a spacesuit into a capsule chair is nonsense. Either we have a full-fledged protective capsule like the B-58 and a protected pilot, or a spacesuit. The spacesuit + capsule is butter, the pilots will just beat you))).
        2 Why do you need UK for a civil liner? Firstly, it flies at altitudes up to 12 km, and there it is not even necessary to supply oxygen to the mask "under excess", and an altitude-compensating suit is not needed either. We have Tu-144 only on pedestals, but there the pilot was fully protected by the VKK and the spacesuit in this case is redundant because the height is not higher than 18 km (I was told that even on regular flights, the pilots entered the cockpit, took off their jackets and put on the VKK, but I cannot say because I myself do not fully believe, but during the tests it was so for sure).
        3 Spacesuits themselves are integrated with ejection seats (SC "Strizh" and "Baklan"). Then, the spacesuit protects from fire more than enough, unless of course you are going to push a person into the cremator chamber. And then, "Swift" in this regard has the highest level of fire resistance because was developed for Buran and the possibility of ejection at altitudes up to 40 km and at speeds up to M = 4, and such ejection was carried out (I will also talk about this in the article over time).
        4 In "all-metal" (or more correctly "in a hard-type spacesuit"), are you ready to eject yourself? ))))) Then on the tin case of the suit, you can immediately glue the label "canned ground" (((((.
        5 The specificity of the use of spacesuits implies protection in high-altitude flights and the stratosphere, this is not an attack aircraft that is exposed to dense fire, incl. small arms, and when ejected, any weight is a potential injury to the pilot.
        So everything here is not as straightforward as we would like.
        PS And the networks in the American ejection seat, about which there was recently an article - these are dozens of future severed hands - this is also not how chairs do))))))
        1. ycuce234-san
          ycuce234-san 30 December 2020 12: 57
          Astronauts, by the way, have obtained a convenient and applicable "integral" - the Astronaut Maneuvering Unit. And for pilots, difficulties with an integral capsule are lagging behind - although the exit from the capsule with Gagarin's parachute on a chair was provided even when there was even a triple integration: a capsule (into a ship) - into a capsule an ejection seat - into a chair by a man in a spacesuit.
          If there is no ejection, there are no problems with the mass and you can make mass commercial metal spacesuits for GA - fires and explosive decompressions are regularly present in the causes of the disaster.
          That is, the applicability of such protective technology is not at all associated with extreme altitude, but rather with technical and emergency risks and can be a subject of discussion and reflection.
          1. Bshkaus
            30 December 2020 13: 17
            Do not forget that Gagarin was the first. They tried to fully implement the "refusal to refuse" principle. Gagarin was catapulted at an altitude of 8 km while the SC defended in a vacuum. He even considered the option of depressurization, when Gagarin was without gloves and the SK still ensured tightness in this case due to the wrist inflatable cuffs while the hands remained bare (the glazing flap lowered automatically when the pressure dropped to 500 mm Hg.
            The Vostok capsule is a spaceship; it should not be confused with a launch vehicle. The Americans launched Mercury both at Redstone and a little later with Atlas.
            Do not confuse "explosive decompression" and "depressurization" either: explosive decompression is a depressurization with a clearly specified gas outflow rate, which should not exceed the pressure equalization rate for more than 0,3 sec. Anything that is longer is the usual depressurization. You will not get explosive decompression on a civil aircraft due to the large volumes of the cabin, and if you do, the fuselage should break longitudinally, after which it is no longer important for you to have any rescue systems ((((.
            And once again about a rigid (metal) spacesuit for aviation - this is nonsense))))
            1. ycuce234-san
              ycuce234-san 30 December 2020 13: 41
              One comrade did not obey the smart ones and began to rivet his rockets out of steel and he succeeded - this suggests that you need to think and try.
              Liner Aloha Airlines 243, for example, landed just after an explosive decompression.
              In principle, in astronautics, too, stagnation in such matters - for example, the autonomous flight station of the Grumman corporation - it was invented in 70-80, but never made.
  4. xomaNN
    xomaNN 29 December 2020 22: 05
    The suits look like a fant. films of the 50s. Almost alien belay