Spacesuit "Yastreb" for work in open space

After A.A.Leonov's successful exit into open space, which in its essence confirmed the fundamental possibility of finding a person in open space, the designers faced a new task of creating a spacesuit for practical work outside the ship.

This need arose primarily because the Soviet lunar program provided for the transfer of astronauts in Earth orbit from the Soyuz transport vehicle to a spacecraft for circling the Moon by crossing open space.

The Berkut spacesuit for AA Leonov's spacewalk, firstly, did not provide the required duration of autonomous operation (up to two hours), since other tasks were assigned to it. Secondly, the new SC was to be used only for extravehicular activities and put on immediately before leaving, while the Berkut SC performed a double function - as a rescue SC at the stages of launching into orbit and entering the dense layers of the atmosphere, and SC for extravehicular activity. Thirdly, the experience gained when A.A. Leonov came out required significant improvements, including due to the transition from open-type coolant to closed-type coolant.

The shell of the new spacesuit, which received its own name "Hawk", was made on the basis of the shell of the "Berkut" spacesuit, but with significant modifications.

Like SC "Berkut", "Yastreb" had a double hermetic shell, double glazing, and given the sharp change in external thermal conditions in space - depending on being in the shade or on the sunny side, it was decided to use thermal protection on the Yastreb in the form screen-vacuum insulation, similar to that used at the SC "Berkut".

To facilitate putting on the spacesuit in zero gravity in the utility compartment of the ship, which has a limited volume, the shell of the spacesuit had a cut for the "standing" position, which excluded its use as a rescue spacesuit, since its compatibility with the Kazbek chair was lost. The ventilation suit was permanently attached to the inner shell of the SC. The sealed cuffs of the sleeves, like the gloves, were removable; instead of leather boots, soft shoes were used, etc.

The GNSh-2 pressure helmet underwent refinement, the light filter in which, unlike the Berkut SC, was located outside, which increased the internal volume of the under-helmet space. In addition, hand mobility has been improved and a compact communications connector has been developed. An emergency oxygen cylinder is installed on the body of the suit, and so on, and the layout of the pressure regulators on the Yastreb shell, in contrast to the Berkut, was made differently.

Power supply, radio communication and control of telemetric parameters were carried out using the onboard systems of the ships with the help of an electrofala.

Technical characteristics of SC "Yastreb"

The time spent outside the ship is up to 3 hours.
Spacesuit absolute pressure:
Mode No. 1 (working) - within 270-340 mm Hg. Art. (0,4 kgf / cm²)
Mode No. 2 (emergency) - within 180-230 mm Hg. Art. (0,27 kgf / cm²)
The maximum heat removal provided by the RVP-1 coolant is 200 kcal / hour.
Gas leakage through the pressure suit shell - no more than 1 l / m.
The weight of the suit is up to 19,5 kg.

Coolant system SK "Yastreb" RVP-1 and RVP-1P

Coolant system for SC "Yastreb" was made in two versions:

1 - in the form of a back pack (RVP-1);
2 - in the form of placement in front of the legs on the harness (RVP-1P).

The version of the hanging knapsack was caused by the narrow hatch of the Soyuz spacecraft, the diameter of which was 600 mm and made it difficult to pass in a spacesuit with a knapsack placed on the back.

On January 17, 1969, the Soyuz-4 and Soyuz-5 spacecraft successfully docked in orbit, and the cosmonauts A.S. Eliseev and E.V. Khrunov, dressed in the Yastreb spacesuits, successfully transferred from the Soyuz-5 spacecraft. "In the Soyuz-4 spacecraft through open space and descended on another spacecraft to earth. The stay in open space during the transition from ship to ship was 37 minutes.

Comments

[yehat2]

Since childhood, I have been tormented by the constant question - if there is an OPEN space and, in general, it is understandable, that is, it is also closed, and this is what it is, I do not understand.

[Bshkaus]

if there is an OPEN space and in general it is understandable, then there is also a closed space, and this is what it is, I don’t understand.

These are relative concepts of the location of a particular object.
"Open space" means the location of an object in outer space.
For example, a spacecraft flies in open space, but the astronaut is inside the spacecraft, the concept of "being in space", "space flight" is applied to it - you can conventionally call it closed space.
But when he (the astronaut) leaves the spaceship, he goes out into open space, the person in this case becomes an object located directly in outer space - open space.
There are other concepts: autonomous work. For example, during airlock, as long as the pressure is released, the spacesuit is powered from the board, but after undocking the pad, autonomous work begins, but the astronaut is still in the airlock with the door open, but he is not yet in "open space" it hits only after leaving the gateway.

[Pete mitchell]

Nice topic, great presentation. I thank the author and look forward to continuing

[Bshkaus]

Nice topic, great presentation. I thank the author and look forward to continuing

In a week about the lunar ones, I'll start, and then I'll speak at the conference a week later on a promising lunar moon, maybe I'll share it a little later, although in my opinion it's not interesting (self-critical).

[Pete mitchell]

Why not? People with diverse interests, one must try for the joy of society

[Bshkaus]

Why not? People with varied interests

it's not about interests, but about the content itself, which boils down to the fact that the "industry" can offer three options for a flight to the moon, but in order to choose which one you need, you must first decide what you are going to the moon do)))

[Pete mitchell]

here's one thing and find out

[210ox]

In general, the Soviet lunar program was closed for uninitiated people for a long time. I would like to read about the descent module. And in general, what the flight should look like, its stages. Thanks for the articles.

[bistrov.]

Quote: yehat2

if there is OPEN space

These are the features of the Russian language, for example, in the "open" sea, in the "open" ocean, in the "open" space, ... that is. directly in the designated environment ... what is not clear here ...

[Flooding]

Quote: bistrov.

what is incomprehensible

there are many interesting riddles in the Russian language

[mojohed2012]

Again, good and interesting material.

[Vladimir_2U]

Amazing stuff!

Coolant system for SC "Yastreb" was made in two versions:

Here's where else I would find out about it!

[Bshkaus]

Here's where else I would find out about it!

But the Hawk's coolant was conditionally autonomous, he all the same had an electrophalus. But the lunar Eagle (about him the next article) was already completely autonomous. The star did not waste time on trifles and made two completely different spacesuits for the Moon at once: as a result, Krechet was chosen for L3, and Oryol looked after Chelomey for his LK-700. ))) so there were options

[Aviator_]

January 17, 1965 Soyuz-4 and Soyuz-5 spacecraft successfully docked in orbit, and cosmonauts A.S. Eliseev and E.V.

It was in 1969 year

[Bshkaus]

It was in 1969 year

I agree, this is a typo (I confused the campaign with Leonov's exit).

[Gimlet]

Thanks to the author for another interesting article! It seems that I read a lot (and I do!) Memoirs, documentary and other literature on space topics. But there are few places where the technical and design features of technology are described in such detail.
A question arose that, perhaps, has little to do with the topic, but still I want to ask: if the working pressure in the spacesuit was 0,4 kgf / cm2, and in the Soyuz capsules, as you know, the working pressure is approximately equal to 1 atm., Then in In the process of putting on the spacesuit, was there time allowed for the astronaut to adapt to work in a lower pressure environment?
Still, the pressure of 0,4 kgf / cm2 is "above 6000m above sea level." To such a height without intermediate adaptations, without having received the possible unpleasant consequences of decompression sickness, it is rather difficult to climb even for trained climbers ...

[Bshkaus]

A question arose that, perhaps, has little to do with the topic, but still I want to ask: if the working pressure in the spacesuit was 0,4 kgf / cm2, and in the Soyuz capsules, as you know, the working pressure is approximately equal to 1 atm., Then in In the process of putting on the spacesuit, was there time allowed for the astronaut to adapt to work in a lower pressure environment?
Still, the pressure of 0,4 kgf / cm2 is "above 6000m above sea level." To such a height without intermediate adaptations, without having received the possible unpleasant consequences of decompression sickness, it is rather difficult to climb even for trained climbers ...

This question is related to the topic and is very relevant!
Problems with the transition from a pressure of 1 atmosphere to 0,4 (300 mm Hg) are not as terrible as they paint it:
Indeed, this is an altitude of about 7 km, but a 100% oxygen environment is maintained inside the spacesuit, due to which the partial pressure of oxygen is even higher than in ordinary terrestrial conditions.
As for the pressure drop, it does not occur instantly, but smoothly, there may be problems with ear congestion, as in a passenger plane, only more pronounced, but given that astronauts take people whose barofunction is usually normal, then problems, as a rule, does not arise.

But the prevention of the risk of developing high-altitude decompression sickness really has to be taken into account because the height in the UK is 7 km. For this, the so-called "desaturation" is performed. At first, a 100% oxygen environment is created inside the spacesuit, and then the astronaut breathes pure oxygen for 30 minutes so that nitrogen is washed out of the body.

But to call it "adaptation" is not correct, a person quickly adapts to a drop in pressure and a change in gas composition, this does not pose a problem for him.

[Gimlet]

Thanks for the clarifications, but questions remain
So, as I understand it, the process of putting on or "entering" a spacesuit is as follows:
1) the astronaut puts on / enters the spacesuit and seals it;
2) the first 30 minutes in the spacesuit, the pressure is 1 atm., But the composition is almost pure oxygen, nitrogen "comes out" of the blood, and so on. gases;
3) the pressure gradually decreases to a working level of 0,4 atm. for some not long period of time (or during the first 30 minutes does the gas composition change and the pressure decrease simultaneously?);
4) an astronaut in a spacesuit is ready to perform assigned tasks.
Then it turns out that the process of removing / exiting the spacesuit is not much easier, as it seems to me: it is only necessary to smoothly raise the pressure, a change in the gas composition can occur abruptly: opened the pressure helmet and that's it!
Then more questions - it turns out that inside the ship, for example, at launch, the pressure inside the spacesuit is lower than in the capsule itself. The spacesuit, for the most part, should crimp the astronaut ... And in all the photo / video frames, the spacesuits look like down jackets ...
And yet - I read somewhere that pure oxygen, without consequences, a person can breathe for about 7 days. Then there are irreversible changes in the lung tissue. We did experiments in pressure chambers. Does such a limitation really exist or is it a story?

[Bshkaus]

First, check the tightness, then a small release of pressure in the sluice to an altitude of 3 km where the gas composition changes: purging with pure oxygen for 5 minutes (280 liters are consumed for this) and then 30m desaturation. Then the pressure in the SC and the sluice is released to a height of 7 km (in the SC it is already clean 02 and desaturation has passed). Up to this point, there is overpressure in the SC. Further, the pressure in the sluice continues to drop, and 280-300 mm remain in the spacecraft. Moreover, the more the external falls, the more the internal (excess) grows. When they reach a vacuum, 0,4 atmospheres (300 mm Hg) are formed in the SC already in the vacuum, the electrofal and the side block are undocked, and the SC switches to autonomous mode. The reverse is both simpler and more difficult: first, the connection of the pads and the electrophalus, then the sublimator is dried for 30-40 minutes, and only after that the pressure increase in the airlock decreases as the excess in the SC decreases (at this moment the spacesuit begins to deflate and envelop the body and at a height of 7 km the pressure of the airlock and SC levels off (300 mm Hg). Further to the "ground" it rises here and there evenly. Switching from 02 to normal air is just opening the hatch.

[Bshkaus]

Now by 02: the Americans flew with him to the moon for up to 2 weeks and nothing, there were changes, but their significance is very exaggerated: 02 is toxic at high pressures of 2-7 atmospheres (from diving problems). There is a direct dependence on his pressure and the time spent before the onset of intoxication and its strength.
But there is an ambush: divers have a higher pressure, you pour water into a glass of 200 ml and drink, and because of the high water pressure, it turned out not 200, but 1000 ml with all the consequences. And in aviation, on the contrary, you pour 200 into a glass, and drink only 40 ml (5 times less, because all the water was smeared into 5 glasses. With oxygen also: pressure 0,3, concentration 100% and the molecules themselves necessary for breathing are exactly as much as you need (well, a little more). This is the secret that lunar experts and lovers of physiology do not know and do not understand))) yes, edema also begins there and the absorption worsens, there are no other energy gases, but up to 2-4 weeks a person can fly like this without serious consequences - but further the chapel))))

[Gimlet]

Thanks for the detailed story! I just haven't read such details anywhere. A lot has been written and filmed about divers and their problems. But about pilots and cosmonauts ... Alas! It is clear that secrecy is also less accessible ...
Now I more or less understand how and what is happening. In general terms, the whole process was roughly what I imagined, but without details. I knew about the "trick" with a reduced pressure of a purely oxygen atmosphere in astronauts before. The question was precisely about the safe terms of being in such an atmosphere with a reduced pressure ... Thank you again! Keep on telling, very exciting.

[Bshkaus]

The question was precisely about the safe period of being in such an atmosphere with a reduced pressure.

in the American literature of the 60s, it was sincerely believed that at a pressure of 0,3 and 100 o2, one can stay indefinitely. But additional experiments and practice have shown that the safe limit is 2-4 weeks.

[Gimlet]

In literature? Is this science fiction?
Have they not already conducted experiments? Didn't you study this question? How did they expect to send people into space then? Without a margin of "strength"? No reserve?
Although ... It is quite possible! They then, in the 60s, used a lot of things without proper verification and testing. The same "Saturn-5" - the first manned flight immediately after the emergency launch. The lunar lander - never really tested - was immediately thrown to the moon. No reserve. And if, upon landing, the module would have landed with a roll higher than the calculated one? What a boulder under a layer of dust would have fallen under the support ... And the very scheme of landing - fly forward with your feet and face down, choosing a landing site ... Supermen!
In general, their entire space program of the 60-70s is on the verge of a fall!