The Orion multi-mission transport spacecraft has been developed by NASA and Lockheed Martin since the mid-2000s and already completed its first unmanned test flight in December 2014. With the help of Orion, cargo and astronauts will be launched into space, but that’s not all that this ship is capable of. In the future, it will be Orion that will have to deliver people to the surface of the Moon and Mars. When creating the ship, its developers used many interesting technologies and new materials, one of which we would like to tell you about today. As astronauts travel towards asteroids, the Moon or Mars, they will be treated to stunning views of space through small windows in the spacecraft's hull. NASA engineers are striving to make these windows to space stronger, lighter and cheaper to produce than previous spacecraft. In the case of the ISS and Space Shuttle, the windows were made of laminated glass. In the case of Orion, acrylic plastic will be used for the first time, which will significantly improve the integrity of the ship's windows. “Glass window panels have historically been part of the ship's shell, maintaining the necessary pressure inside the ship and preventing the death of astronauts. The glass should also protect the crew as much as possible from the enormous temperature upon entry into the Earth’s atmosphere. But the main disadvantage of glass is its structural imperfection. Under heavy loads, the strength of glass decreases over time. When flying in space, this weak point can play a cruel joke on the ship,” says Linda Estes, head of the window subsystems department at NASA. It is precisely because glass is not an ideal material for portholes that engineers have been constantly looking for a more suitable material for this. There are many structurally stable materials in the world, but only a few are transparent enough to be used to create portholes. In the early stages of Orion's development, NASA tried to use polycarbonates as a material for the windows, but they did not meet the optical requirements necessary for obtaining high-resolution images. After this, the engineers switched to acrylic material, which provided the highest transparency and enormous strength. In the USA, huge aquariums are made from acrylic, which protect their inhabitants from the environment that is potentially dangerous to them, while withstanding enormous water pressure. Today, Orion is equipped with four windows built into the crew module, as well as additional windows in each of the two hatches. Each porthole consists of three panels. The inner panel is made of acrylic, and the other two are still made of glass. It was in this form that Orion had already been in space during its first test flight. During this year, NASA engineers must decide whether they can use two acrylic panels and one glass in the windows. In the coming months, Linda Estes and her team are scheduled to conduct what they call a “creep test” on the acrylic panels. Creep in this case is a slow deformation of a solid that occurs over time under the influence of a constant load or mechanical stress. All solids, without exception, are subject to creep - both crystalline and amorphous. Acrylic panels will be tested for 270 days under enormous loads. Acrylic windows should make the Orion ship significantly lighter, and their structural strength will eliminate the risk of the windows breaking due to accidental scratches and other damage. According to NASA engineers, thanks to acrylic panels, they will be able to reduce the weight of the ship by more than 90 kilograms. Reducing the mass will make it much cheaper to launch a ship into space. Switching to acrylic panels will also reduce the cost of building Orion-class ships, because acrylic is much cheaper than glass. It will be possible to save about $2 million on windows alone during the construction of one spacecraft. Perhaps in the future glass panels will be completely excluded from windows, but for now this requires additional thorough testing. Taken from hi-news.ru
When looking at a spacecraft, one's eyes usually widen. Unlike an airplane or a submarine with extremely sleek lines, there are a lot of different blocks, structural elements, pipelines, cables sticking out from the outside... But there are also details on board that are clear to anyone at first glance. Here are the portholes, for example. Just like planes or sea planes! In fact, this is far from true...
From the very beginning of space flights, the question was: “What’s overboard - it would be nice to see!” That is, of course, there were certain considerations in this regard - astronomers and astronautics pioneers tried, not to mention science fiction writers. In Jules Verne's novel From the Earth to the Moon, the heroes set off on a lunar expedition in a projectile equipped with glass windows with shutters. The characters of Tsiolkovsky and Wells look out into the Universe through large windows.
When it came to practice, the simple word “window” seemed unacceptable to space technology developers. Therefore, what astronauts can look out of the spacecraft through is called, no less, special glazing, and less “ceremoniously” - portholes. Moreover, the porthole itself for people is a visual porthole, and for some equipment it is an optical one.
Windows are both a structural element of the spacecraft shell and an optical device. On the one hand, they serve to protect the instruments and crew located inside the compartment from the influence of the external environment, on the other hand, they must provide the ability to operate various optical equipment and visual observation. Not only observation, however - when on both sides of the ocean they were drawing equipment for “star wars”, they assembled and aimed through the windows of warships.
Americans and English-speaking rocket scientists in general are perplexed by the term “porthole”. They ask again: “Are these windows, or what?” In English, everything is simple - whether in the house or in the Shuttle - window, and no problems. But English sailors say porthole. So Russian space window manufacturers are probably closer in spirit to overseas shipbuilders.
Two types of windows can be found on observation spacecraft.
The first type completely separates the filming equipment located in the pressurized compartment (lens, cassette part, image receivers and other functional elements) from the “hostile” external environment. Zenit-type spacecraft are built according to this scheme.
The second type of porthole separates the cassette part, image receivers and other elements from the external environment, while the lens is located in an unsealed compartment, that is, in a vacuum. This scheme is used on Yantar-type spacecraft. With such a design, the requirements for the optical properties of the porthole become especially stringent, since the porthole is now an integral part of the optical system of the filming equipment, and not a simple “window into space.”
It was believed that the astronaut would be able to control the spacecraft based on what he could see. To a certain extent this was achieved. It is especially important to “look forward” during docking and when landing on the Moon - there, American astronauts more than once used manual controls during landings.
For most astronauts, the psychological idea of up and down is formed depending on the surrounding environment, and portholes can also help with this. Finally, portholes, like windows on Earth, serve to illuminate compartments when flying over the illuminated side of the Earth, Moon or distant planets.
Like any optical device, a ship's window has a focal length (from half a kilometer to fifty) and many other specific optical parameters.
When creating the first spaceships in our country, the development of portholes was entrusted to Research Institute of Aviation Glass of the Ministry of Aviation Industry(now this OJSC "Research Institute of Technical Glass"). They also took part in the creation of “windows to the Universe” State Optical Institute named after. S.I. Vavilova, Research Institute of Rubber Industry, Krasnogorsk Mechanical Plant and a number of other enterprises and organizations. The Moscow region made a great contribution to the melting of various brands of glass, the manufacture of portholes and unique long-focus lenses with large apertures. Lytkarino Optical Glass Plant.
The task turned out to be extremely difficult. At one time, mastering the production of aircraft flashlights took a long time and was difficult - the glass quickly lost its transparency and became covered with cracks. In addition to ensuring transparency, the Patriotic War forced the development of armored glass; after the war, the increase in the speed of jet aircraft led not only to increased requirements for strength, but also to the need to preserve the properties of glazing during aerodynamic heating. For space projects, the glass that was used for canopies and airplane windows was not suitable - the temperatures and loads were not the same.
The first space windows were developed in our country on the basis of Resolution of the Central Committee of the CPSU and the Council of Ministers of the USSR No. 569-264 of May 22, 1959, which provided for the start of preparations for manned flights. Both in the USSR and in the USA, the first portholes were round - these were easier to calculate and manufacture. In addition, domestic ships, as a rule, could be controlled without human intervention, and, accordingly, there was no need for too good an aircraft-like overview. Gagarin's Vostok had two windows. One was located on the entrance hatch of the descent vehicle, just above the astronaut’s head, the other was located at his feet in the body of the descent vehicle.
It’s not out of place to recall the names of the main developers of the first windows at the Aviation Glass Research Institute - S.M. Brekhovskikh, V.I. Alexandrov, H.E. Serebryannikova, Yu.I. Nechaev, L.A. Kalashnikova, F.T. Vorobyov, E.F. Postolskaya, L.V. King, V.P. Kolgankov, E.I. Tsvetkov, S.V. Volchanov, V.I. Krasin, E.G. Loginova and others.
Due to many reasons, when creating their first spacecraft, our American colleagues experienced a serious “mass shortage.” Therefore, they simply could not afford a level of automation in ship control similar to the Soviet one, even taking into account lighter electronics, and many functions for controlling the ship were limited to experienced test pilots selected for the first cosmonaut corps. At the same time, in the original version of the first American spacecraft “Mercury” (the one about which they said that the astronaut does not enter it, but puts it on himself), the pilot’s window was not provided at all - even the required 10 kg of additional mass was nowhere to be found.
The window appeared only at the urgent request of the astronauts themselves after Shepard’s first flight. A real, full-fledged “pilot’s” window appeared only on the Gemini - on the crew’s landing hatch. But it was made not round, but of a complex trapezoidal shape, since for full manual control when docking the pilot needed forward visibility; On the Soyuz, by the way, a periscope was installed on the window of the descent module for this purpose. The Americans developed portholes by Corning, while the JDSU division was responsible for glass coatings.
On the command module of the lunar Apollo, one of the five windows was also placed on the hatch. The other two, which ensured approach when docking with the lunar module, looked forward, and two more “side” ones made it possible to glance perpendicular to the longitudinal axis of the ship. On the Soyuz there were usually three windows on the descent module and up to five on the service compartment. The majority of windows are on orbital stations - up to several dozen, of different shapes and sizes.
An important stage in “window construction” was the creation of glazing for space planes – the Space Shuttle and Buran. Shuttles land like an airplane, which means the pilot needs to have a good view from the cockpit. Therefore, both American and domestic developers provided six large windows of complex shape. Plus a pair in the roof of the cabin - this is to ensure docking. Plus there are windows in the rear of the cabin for payload operations. And finally, along the porthole on the entrance hatch.
During dynamic phases of flight, the front windows of the Shuttle or Buran are subject to completely different loads, different from those to which the windows of conventional descent vehicles are exposed. Therefore, the calculation of strength is different here. And when the shuttle is already in orbit, there are “too many” windows - the cabin overheats, and the crew receives extra “ultraviolet light”. Therefore, during an orbital flight, some of the windows in the Shuttle cabin are closed with Kevlar shutters. But the Buran had a photochromic layer inside the windows, which darkened when exposed to ultraviolet radiation and did not allow “extra” into the cabin.
The main part of the porthole is, of course, glass. “For space”, not ordinary glass is used, but quartz. During the “Vostok” era, the choice was not particularly large - only the SK and KV brands were available (the latter is nothing more than fused quartz). Later, many other types of glass were created and tested (KV10S, K-108). They even tried to use SO-120 plexiglass in space. Americans know the Vycor brand of thermal and impact-resistant glass.
Glass of different sizes is used for windows - from 80 mm to almost half a meter (490 mm), and recently an eight-hundred-millimeter “glass” appeared in orbit. External protection of “space windows” will be discussed later, but to protect crew members from the harmful effects of near-ultraviolet radiation, special beam-splitter coatings are applied to the windows of windows working with non-stationary installed devices.
A porthole is not just glass. To obtain a durable and functional design, several glasses are inserted into a holder made of aluminum or titanium alloy. They even used lithium for the Shuttle's windows.
To ensure the required level of reliability, several glasses were initially made in the porthole. If something happens, one glass will break, and the rest will remain, keeping the ship airtight. Domestic windows on the Soyuz and Vostok had three glasses each (the Soyuz has one double-glass window, but it is covered by a periscope for most of the flight).
On the Apollo and Space Shuttle, the “windows” are also mostly three-glass, but the Americans equipped the Mercury, their “first swallow,” with a four-glass porthole.
Unlike the Soviet ones, the American porthole on the Apollo command module was not a single assembly. One glass worked as part of the shell of the load-bearing heat-protective surface, and the other two (essentially a two-glass porthole) were already part of the pressurized circuit. As a result, such portholes were more visual than optical. Actually, given the key role of pilots in managing Apollo, this decision seemed quite logical.
On the Apollo lunar cabin, all three windows themselves were single-glass, but on the outside they were covered by external glass, which was not part of the pressurized circuit, and from the inside by internal safety plexiglass. More single-glass windows were subsequently installed at orbital stations, where the loads are still less than those of spacecraft descent vehicles. And on some spacecraft, for example, on the Soviet interplanetary stations “Mars” in the early 70s, several windows (double-glass compositions) were actually combined in one frame.
When a spacecraft is in orbit, the temperature difference on its surface can be a couple of hundred degrees. The expansion coefficients of glass and metal are naturally different. So seals are placed between the glass and the metal of the cage. In our country, they were dealt with by the Scientific Research Institute of the Rubber Industry. The design uses vacuum-resistant rubber. Developing such seals is a difficult task: rubber is a polymer, and cosmic radiation eventually “chops” the polymer molecules into pieces, and as a result, “ordinary” rubber simply creeps apart.
Upon closer examination, it turns out that the design of domestic and American “windows” differs significantly from each other. Almost all glass in domestic designs is cylindrical in shape (naturally, with the exception of the glazing of winged craft such as “Buran” or “Spiral”). Accordingly, the cylinder has a side surface that must be specially treated to minimize glare. For this purpose, the reflective surfaces inside the porthole are covered with special enamel, and the side walls of the chambers are sometimes even covered with semi-velvet. The glass is sealed with three rubber rings (as they were first called - rubber seals).
The glass of the American Apollo spacecraft had rounded side surfaces, and a rubber seal was stretched over them, like a tire on a car rim.
It is no longer possible to wipe the glass inside the window with a cloth during the flight, and therefore no debris should categorically get into the chamber (the space between the glass). In addition, the glass should neither fog up nor freeze. Therefore, before launch, not only the tanks of the spacecraft are filled, but also the windows - the chamber is filled with especially pure dry nitrogen or dry air. To “unload” the glass itself, the pressure in the chamber is provided to be half that in the sealed compartment. Finally, it is desirable that the inside surface of the compartment walls is not too hot or too cold. For this purpose, an internal plexiglass screen is sometimes installed.
Glass is not metal; it breaks down differently. There will be no dents here - a crack will appear. The strength of glass depends mainly on the condition of its surface. Therefore, it is strengthened by eliminating surface defects - microcracks, nicks, scratches. To do this, glass is etched and tempered. However, glass used in optical instruments is not treated this way. Their surface is hardened by so-called deep grinding. By the early 70s, the outer glass of optical windows could be strengthened by ion exchange, which made it possible to increase their abrasive resistance.
To improve light transmission, the glass is coated with a multilayer antireflective coating. They may contain tin oxide or indium. Such coatings increase light transmission by 10–12%, and they are applied using reactive cathode sputtering. In addition, indium oxide absorbs neutrons well, which is useful, for example, during a manned interplanetary flight. Indium is generally the “philosopher’s stone” of the glass, and not only glass, industry. Indium-coated mirrors reflect most of the spectrum equally. In rubbing units, indium significantly improves abrasion resistance.
During flight, windows can also become dirty from the outside. After the start of flights under the Gemini program, the astronauts noticed that fumes from the heat-protective coating were settling on the glass. Spacecraft in flight generally acquire a so-called accompanying atmosphere. Something is leaking from the pressurized compartments, small particles of screen-vacuum thermal insulation are “hanging” next to the ship, and there are combustion products of fuel components during operation of the attitude control engines... In general, there is more than enough debris and dirt to not only “spoil” view”, but also, for example, disrupt the operation of on-board photographic equipment.
Developers of interplanetary space stations from NPO im. S.A. Lavochkina they say that during the flight of the spacecraft to one of the comets, two “heads” - nuclei - were discovered in its composition. This was recognized as an important scientific discovery. Then it turned out that the second “head” appeared as a result of fogging of the porthole, which led to the effect of an optical prism.
The windows of the windows should not change light transmission when exposed to ionizing radiation from background cosmic radiation and cosmic radiation, including as a result of solar flares.
The interaction of electromagnetic radiation from the Sun and cosmic rays with glass is generally a complex phenomenon. Absorption of radiation by glass can lead to the formation of so-called “color centers,” that is, a decrease in the initial light transmission, and also cause luminescence, since part of the absorbed energy can immediately be released in the form of light quanta.
The luminescence of the glass creates an additional background, which reduces the image contrast, increases the noise-to-signal ratio and can make the normal functioning of the equipment impossible. Therefore, glass used in optical windows must have, along with high radiation-optical stability, a low level of luminescence. The magnitude of luminescence intensity is no less important for optical glasses operating under the influence of radiation than color resistance.
Among the factors of space flight, one of the most dangerous for windows is micrometeor impact. This leads to a rapid decrease in the strength of the glass. Its optical characteristics also deteriorate.
After the first year of flight, craters and scratches reaching one and a half millimeters are found on the external surfaces of long-term orbital stations. While most of the surface can be shielded from meteoric and man-made particles, the windows cannot be protected this way.
To a certain extent, lens hoods, sometimes installed on the windows through which, for example, on-board cameras operate, help. On the first American orbital station, Skylab, it was assumed that the windows would be partially shielded by structural elements. But, of course, the most radical and reliable solution is to cover the “orbital” windows from the outside with controllable covers. This solution was applied, in particular, at the second-generation Soviet orbital station Salyut-7.
There is more and more “garbage” in orbit. On one of the Shuttle flights, something clearly man-made left a rather noticeable pothole-crater on one of the windows. The glass survived, but who knows what might come next time?.. This, by the way, is one of the reasons for the serious concern of the “space community” about the problems of space debris. In our country, in particular, Professor Samara State Aerospace University L.G. Lukashev.
The windows of the descent vehicles operate under even more difficult conditions. When descending into the atmosphere, they find themselves in a cloud of high-temperature plasma. In addition to the pressure from inside the compartment, external pressure acts on the window during descent. And then comes the landing - often on snow, sometimes in water. At the same time, the glass cools sharply. Therefore, special attention is paid to issues of strength here.
"The simplicity of the porthole–this is an apparent phenomenon. Some opticians say that creating a flat porthole–the task is more complex than manufacturing a spherical lens, since building a mechanism of “exact infinity” is much more difficult than a mechanism with a finite radius, that is, a spherical surface. And yet, there have never been any problems with the windows,”- this is probably the best assessment for a spacecraft assembly, especially if it came from the mouth Georgy Fomin, in the recent past - first deputy general designer of the State Scientific Research and Design Center "TsSKB - Progress".
Not so long ago - on February 8, 2010, after the Shuttle flight STS-130 - an observation dome appeared on the International Space Station, consisting of several large quadrangular windows and a round eight-hundred-millimeter window.
The Cupola module is designed for Earth observations and work with a manipulator. It was developed by the European concern Thales Alenia Space, and was built by Italian mechanical engineers in Turin.
Thus, today the Europeans hold the record - such large windows have never been put into orbit either in the USA or in Russia. The developers of various “space hotels” of the future also talk about huge windows, insisting on their special significance for future space tourists. So “window construction” has a great future, and windows continue to be one of the key elements of manned and unmanned spacecraft.
"Dome"–really cool stuff! When you look at the Earth from a porthole, it’s like looking through an embrasure. And in the “dome” there is a 360-degree view, you can see everything! The earth from here looks like a map, yes, most of all it resembles a geographical map. You can see how the sun goes away, how it rises, how the night approaches... You look at all this beauty with some kind of freezing inside.”
From the diary of cosmonaut Maxim Suraev.
ARE WE FLYING?? ?)) In what city and how are windows for spaceships made? and got the best answer
Answer from Mask Incognito[guru]
The window of a spacecraft (SV) performs two main functions. First, it must have the appropriate range and level of transmission and reflection of electromagnetic radiation, ensuring the operation of an optical instrument or visual observation with a minimum of distortion and interference.
Secondly, being part of the spacecraft shell, it must, while maintaining its integrity, provide protection for the crew and equipment from the effects of factors in outer space and the earth’s atmosphere.
With prolonged use of windows on board a spacecraft, the likelihood of damage increases; on the outer surface of the glass, under the influence of micrometeorites, cosmic dust and debris, craters, gouges, and scratches of various sizes and shapes are formed, which raises concerns about the reliability of the product.
The launch of a long-term orbital ISS necessitated the need to study the long-term strength and durability of optical elements damaged by impacts of microparticles during ground-based modeling, analyze and systematize emerging mechanical defects, scientific and technical substantiation of permissible and critical defects, develop a methodology for examining the condition of windows in orbit, and issue reports on operability portholes with defects.
The cabin of the first spacecraft is much more spacious than a typical pilot's cabin on an airplane. The device has three
porthole with heat-resistant glass and two quick-opening hatches. 
The cabin of the Vostok spacecraft was equipped with three windows (forward and side views), while the cabin of the Mercury spacecraft was equipped with only one (in front of the astronaut). 
spaceship window 7K. Photo 1966
Portholes were produced at the Avtosteklo plant in Konstantinovka, Donetsk region. They were listed in the “other products” column. Everything was very secret. They made glass for a wide variety of vehicles, including participating in equipping the first nuclear-powered icebreaker "Lenin". Now this enterprise is called Spetstekhsteklo CJSC, it has developed a new multi-layer glazing, launched the production of aviation glass, tempered, multi-layer glass with a thickness of 6.5-70mm, armored (II - IV degrees).
Innovation in the production of special glass - the world's largest sapphire was grown in Ukraine. The process of the appearance of this amazing stone took only 10 days - from July 20 to July 30. In such a short period of time, the stone reached simply incredible dimensions: 80 by 35 by 5 cm and a weight of 45 kilograms. From sapphires of this size and shape it will be possible to make weather-resistant windows for spaceships.
Source:
Answer from 2 answers[guru]
Hello! Here is a selection of topics with answers to your question: ARE WE FLYING?? ?)) In what city and how are windows for spaceships made?
Answer from Alexey Kuznetsov[guru]
I know for sure that the portholes for Tereshkova were made in a small town in the Novgorod region - Malaya Vishera, at a local glass factory. The plant is closed, but the veterans remember personal gratitude from Valya.
Answer from Marina[guru]
At the Gus-Khrustalnensky quartz glass plant.
The plant is truly unique. It is the only one in Russia that has the technology and equipment for the production of highly pure quartz products. Without its glass, the power laser installation will not work, not a single spacecraft will enter orbit. Plus radiation-resistant glass for nuclear power plants, especially pure glass for the chemical industry, quartz substrates for computer displays on liquid crystals, optical fiber, glass for night vision devices, crystalline piezoquartz for mobile and space communications and much more. At the time of the USSR, it belonged to the construction materials industry, the plant worked almost entirely for the defense industry.
There are two main specializations here. Firstly, the production of crystalline quartz, which is what workshop No. 5 specializes in, the same one where expensive Japanese equipment is installed. And this is, first of all, piezoquartz, from which resonators are made for the radio-electronic industry. Its price ranges from 50 to 150 dollars per kilogram. And the potential capacity of the workshop is to produce about 240 tons of these crystals per year. And this is 2.5 - 3 million dollars in profit. .
The second direction is fused quartz, from which the same windows for space stations, substrates for liquid crystal monitors, especially pure glass for the chemical industry, optical fibers, etc. are made.
The Research Institute of Technical Glass, the country's only developer of windows for spaceships, Air Force aircraft and submarines, is on the verge of collapse.
In outer space, at enormous temperatures, any glass in a ship's windows burns out, and as its thickness increases, visibility becomes difficult, since transparency noticeably decreases. An inorganic nanomaterial coating was applied to the outside of the window without changing the optical properties of the glass itself. The outer shell of the Buran was also coated with heat-resistant ceramic compounds based on nanopowders.
At the plant in Samara. 
Creating windows for a spaceship
Portholes with protective glass that does not transmit cosmic rays. There are also replaceable filters that protect against direct sunlight, and a shading mechanism in case of excessive radiation or elevated temperatures.
In most cases, GOI developed the design, manufactured and tested a prototype of each new lens, after which the proven technology was introduced at industry enterprises. It should be noted that in cases where lens developers “did not have enough” glass with the necessary parameters to achieve higher technical or operational characteristics, such glass was specially developed at Branch No. 1 of GOI (NITIOM), and the corresponding melting technologies were also introduced. These works were led by Academician G. T. Petrovsky, an outstanding scientist and founder of optical, including space, materials science. Let us especially mention that under his leadership, research and experiments were also carried out on growing especially pure optical crystals with a reduced number of dislocations in space conditions.
And I want to copy and paste one more article. I originally read it in the Nizhny Novgorod Land newspaper, but the original, it turns out, was published in the Russian Space magazine. While driving from the village to the city, I just started reading. The article talks about the history of the creation of portholes, popularly and intelligibly tells how they are created in our country and in the Americans, what they are made of and where they are used.
When looking at a spacecraft, one's eyes usually widen. Unlike an airplane or a submarine with extremely sleek lines, there are a lot of different blocks, structural elements, pipelines, cables sticking out from the outside... But there are also details on board that are clear to anyone at first glance. Here are the portholes, for example. Just like planes or sea planes! In fact, this is far from true...
WE CUT A WINDOW TO THE UNIVERSE
From the very beginning of space flights, the question was: “What’s overboard? It would be nice to see!” That is, of course, there were certain considerations in this regard - astronomers and astronautics pioneers tried, not to mention science fiction writers. In Jules Verne's novel From the Earth to the Moon, the heroes set off on a lunar expedition in a projectile equipped with glass windows with shutters. The characters of Tsiolkovsky and Wells look out into the Universe through large windows.
A Zenit-type spacecraft before docking with a launch vehicle. The portholes in front of the camera lenses are covered with covers (photo: RSC Energia) When it came to practice, the simple word “window” seemed unacceptable to space technology developers. Therefore, what astronauts can look out of the spacecraft through is called, no less, special glazing, and less “ceremoniously” - portholes. Moreover, the porthole for people is a visual porthole, but for some equipment it is an optical one.
Windows are both a structural element of the spacecraft shell and an optical device. On the one hand, they serve to protect the instruments and crew located inside the compartment from the influence of the external environment, on the other hand, they must provide the ability to operate various optical equipment and visual observation. Not only observation, however - when on both sides of the ocean they were drawing equipment for “star wars”, they assembled and aimed through the windows of warships.
Americans and English-speaking rocket scientists in general are perplexed by the term “porthole”. They ask again: “Are these windows, or what?” In English, everything is simple - whether in the house or in the Shuttle - window, and no problems. But English sailors say porthole. So Russian space window manufacturers are probably closer in spirit to overseas shipbuilders.
Karen Nyberg at the window of the Japanese Kibo module that arrived at the ISS, 2008 (photo: NASA) There are two types of windows on observation spacecraft. The first type completely separates the filming equipment located in the pressurized compartment (lens, cassette part, image receivers and other functional elements) from the “hostile” external environment. Zenit-type spacecraft are built according to this scheme. The second type of porthole separates the cassette part, image receivers and other elements from the external environment, while the lens is located in an unsealed compartment, that is, in a vacuum. This scheme is used on Yantar-type spacecraft. With such a design, the requirements for the optical properties of the porthole become especially stringent, since the porthole is now an integral part of the optical system of the filming equipment, and not a simple “window into space.”
It was believed that the astronaut would be able to control the spacecraft based on what he could see. To a certain extent this was achieved. It is especially important to “look forward” during docking and when landing on the Moon - there, American astronauts more than once used manual controls during landings.
The edge of the Vostok porthole is visible behind the astronaut’s helmet. Most astronauts’ psychological idea of up and down is formed depending on the environment, and portholes can also help with this. Finally, portholes, like windows on Earth, serve to illuminate compartments when flying over the illuminated side of the Earth, Moon or distant planets.
Like any optical device, a ship's window has a focal length (from half a kilometer to fifty) and many other specific optical parameters.
OUR GLAZERS ARE THE BEST IN THE WORLD
When the first spaceships were created in our country, the development of windows was entrusted to the Research Institute of Aviation Glass of the Ministry of Aviation Industry (now it is OJSC Scientific Research Institute of Technical Glass). The State Optical Institute named after. S. I. Vavilova, Research Institute of Rubber Industry, Krasnogorsk Mechanical Plant and a number of other enterprises and organizations. The Lytkarinsky optical glass plant near Moscow made a great contribution to the melting of various brands of glass, the production of portholes and unique long-focus lenses with large apertures.
Porthole on the hatch of the command module of the Apollo spacecraft. The task turned out to be extremely difficult. At one time, mastering the production of aircraft flashlights took a long time and was difficult - the glass quickly lost its transparency and became covered with cracks. In addition to ensuring transparency, the Patriotic War forced the development of armored glass; after the war, the increase in the speed of jet aircraft led not only to increased requirements for strength, but also to the need to preserve the properties of glazing during aerodynamic heating. For space projects, the glass that was used for canopies and airplane windows was not suitable - the temperatures and loads were not the same.
The first space windows were developed in our country on the basis of Resolution of the Central Committee of the CPSU and the Council of Ministers of the USSR No. 569-264 of May 22, 1959, which provided for the start of preparations for manned flights. Both in the USSR and in the USA, the first portholes were round - these were easier to calculate and manufacture. In addition, domestic ships, as a rule, could be controlled without human intervention, and accordingly there was no need for too good an aircraft-like overview. Gagarin's Vostok had two windows. One was located on the entrance hatch of the descent vehicle, just above the astronaut’s head, the other was at his feet in the body of the descent vehicle. It is not at all out of place to recall the names of the main developers of the first windows at the Aviation Glass Research Institute - these are S.M. Brekhovskikh, V.I. Alexandrov, H. E. Serebryannikova, Yu. I. Nechaev, L. A. Kalashnikova, F. T. Vorobyov, E. F. Postolskaya, L. V. Korol, V. P. Kolgankov, E. I. Tsvetkov, S. V. Volchanov, V. I. Krasin, E. G. Loginova and others.
Virgil Grissom and the Liberty Bell capsule. A trapezoidal porthole is visible (photo: NASA) Due to many reasons, when creating their first spacecraft, our American colleagues experienced a serious “mass deficit”. Therefore, they simply could not afford a level of automation in ship control similar to the Soviet one, even taking into account lighter electronics, and many functions for controlling the ship were limited to experienced test pilots selected for the first cosmonaut corps. At the same time, in the original version of the first American spacecraft, Mercury (the one about which they said that the astronaut did not enter it, but put it on himself), the pilot’s window was not provided at all - even the required 10 kg of additional mass was nowhere to be found.
The window appeared only at the urgent request of the astronauts themselves after Shepard’s first flight. A real, full-fledged “pilot’s” window appeared only on the Gemini - on the crew’s landing hatch. But it was made not round, but of a complex trapezoidal shape, since for full manual control when docking the pilot needed forward visibility; On the Soyuz, by the way, a periscope was installed on the window of the descent module for this purpose. The Americans developed portholes by Corning, while the JDSU division was responsible for glass coatings.
On the command module of the lunar Apollo, one of the five windows was also placed on the hatch. The other two, which ensured approach when docking with the lunar module, looked forward, and two more “side” ones made it possible to glance perpendicular to the longitudinal axis of the ship. On the Soyuz there were usually three windows on the descent module and up to five on the service compartment. Most of the windows are on orbital stations - up to several dozen, of different shapes and sizes.
Nasal glazing of the Space Shuttle cabin An important stage in “window construction” was the creation of glazing for space aircraft - the Space Shuttle and Buran. Shuttles land like an airplane, which means the pilot needs to have a good view from the cockpit. Therefore, both American and domestic developers provided six large windows of complex shape. Plus a pair in the roof of the cabin - this is to ensure docking. Plus there are windows in the rear of the cabin for payload operations. And finally, along the porthole on the entrance hatch.
During dynamic phases of flight, the front windows of the Shuttle or Buran are subject to completely different loads, different from those to which the windows of conventional descent vehicles are exposed. Therefore, the calculation of strength is different here. And when the shuttle is already in orbit, there are “too many windows” - the cabin overheats, the crew receives extra “ultraviolet light”. Therefore, during an orbital flight, some of the windows in the Shuttle cabin are closed with Kevlar shutters. But the Buran had a photochromic layer inside the windows, which darkened when exposed to ultraviolet radiation and did not allow “extra” into the cabin.
FRAMES, SHUTTERS, CLATCHES, CARVED WINDOWS...
The main part of the porthole is, of course, glass. “For space”, not ordinary glass is used, but quartz. During the “Vostok” era, the choice was not particularly large - only the SK and KV brands were available (the latter is nothing more than fused quartz). Later, many other types of glass were created and tested (KV10S, K-108). They even tried to use SO-120 plexiglass in space. Americans know the Vycor brand of thermal and impact-resistant glass.
Julie Payette controls Endeavor's manipulator at the ship's ceiling porthole (photo: NASA) Glass of different sizes is used for portholes - from 80 mm to almost half a meter (490 mm), and recently an eight-hundred-millimeter “glass” appeared in orbit. External protection of “space windows” will be discussed later, but to protect crew members from the harmful effects of near-ultraviolet radiation, special beam-splitter coatings are applied to the windows of windows working with non-stationary installed devices.
A porthole is not just glass. To obtain a durable and functional design, several glasses are inserted into a holder made of aluminum or titanium alloy. They even used lithium for the Shuttle's windows.
To ensure the required level of reliability, several glasses were initially made in the porthole. If something happens, one glass will break, and the rest will remain, keeping the ship airtight. Domestic windows on the Soyuz and Vostok had three glasses each (the Soyuz has one double-glass window, but it is covered by a periscope for most of the flight).
On the Apollo and Space Shuttle, the “windows” are also mostly three-glass, but the Americans equipped the Mercury, their “first swallow,” with a four-glass porthole.
Double-glass window (above), three-glass window of the Soyuz family spacecraft (below) (photo: Sergei Andreev) Unlike the Soviet ones, the American window on the Apollo command module was not a single assembly. One glass worked as part of the shell of the load-bearing heat-protective surface, and the other two (essentially a two-glass porthole) were already part of the pressurized circuit. As a result, such portholes were more visual than optical. Actually, given the key role of pilots in managing Apollo, this decision seemed quite logical.
On the Apollo lunar cabin, all three windows themselves were single-glass, but on the outside they were covered by external glass, which was not part of the pressurized circuit, and from the inside by internal safety plexiglass. More single-glass windows were subsequently installed at orbital stations, where the loads are still less than those of spacecraft descent vehicles. And on some spacecraft, for example, on the Soviet interplanetary stations “Mars” in the early 70s, several windows (double-glass compositions) were actually combined in one frame.
When a spacecraft is in orbit, the temperature difference on its surface can be a couple of hundred degrees. The expansion coefficients of glass and metal are naturally different. So seals are placed between the glass and the metal of the cage. In our country, they were dealt with by the Scientific Research Institute of the Rubber Industry. The design uses vacuum-resistant rubber. Developing such seals is a difficult task: rubber is a polymer, and cosmic radiation eventually “chops” the polymer molecules into pieces, and as a result, “ordinary” rubber simply creeps apart.
Upon closer examination, it turns out that the design of domestic and American “windows” differs significantly from each other. Almost all glass in domestic designs is cylindrical in shape (naturally, with the exception of the glazing of winged craft such as “Buran” or “Spiral”). Accordingly, the cylinder has a side surface that must be specially treated to minimize glare. For this purpose, the reflective surfaces inside the porthole are covered with special enamel, and the side walls of the chambers are sometimes even covered with semi-velvet. The glass is sealed with three rubber rings (as they were first called - rubber seals).
The glass of the American Apollo spacecraft had rounded side surfaces, and a rubber seal was stretched over them, like a tire on a car rim.
The first man on the Moon, Neil Armstrong, in the Eagle lunar module (photo: NASA) It is no longer possible to wipe the glass inside the window with a cloth during the flight, and therefore no debris should categorically get into the chamber (the space between the glass). In addition, the glass should neither fog up nor freeze. Therefore, before launch, not only the tanks of the spacecraft are filled, but also the windows - the chamber is filled with especially pure dry nitrogen or dry air. To “unload” the glass itself, the pressure in the chamber is provided to be half that in the sealed compartment. Finally, it is desirable that the inside surface of the compartment walls is not too hot or too cold. For this purpose, an internal plexiglass screen is sometimes installed.
THE LIGHT HAS BEEN A WEDGE ON INDIA. THE LENS TURNED OUT WHAT WE NEED!
Glass is not metal; it breaks down differently. There will be no dents here - a crack will appear. The strength of glass depends mainly on the condition of its surface. Therefore, it is strengthened by eliminating surface defects - microcracks, nicks, scratches. To do this, glass is etched and tempered. However, glass used in optical instruments is not treated this way. Their surface is hardened by so-called deep grinding. By the early 70s, the outer glass of optical windows could be strengthened by ion exchange, which made it possible to increase their abrasive resistance.
One of the windows of the Soyuz descent module is covered with a periscope for most of the flight. To improve light transmission, the glass is coated with a multilayer antireflective coating. They may contain tin oxide or indium. Such coatings increase light transmission by 10-12%, and they are applied using reactive cathode sputtering. In addition, indium oxide absorbs neutrons well, which is useful, for example, during a manned interplanetary flight. Indium is generally the “philosopher’s stone” of the glass, and not only glass, industry. Indium-coated mirrors reflect most of the spectrum equally. In rubbing units, indium significantly improves abrasion resistance.
During flight, windows can also become dirty from the outside. After the start of flights under the Gemini program, the astronauts noticed that fumes from the heat-protective coating were settling on the glass. Spacecraft in flight generally acquire a so-called accompanying atmosphere. Something is leaking from the pressurized compartments, small particles of screen-vacuum thermal insulation are “hanging” next to the ship, and there are combustion products of fuel components during operation of the attitude control engines... In general, there is more than enough debris and dirt to not only “spoil” view”, but also, for example, disrupt the operation of on-board photographic equipment.
(photo: ESA) Developers of interplanetary space stations from NPO im. S.A. Lavochkina says that during the flight of the spacecraft to one of the comets, two “heads” - nuclei - were discovered in its composition. This was recognized as an important scientific discovery. Then it turned out that the second “head” appeared as a result of fogging of the porthole, which led to the effect of an optical prism.
The windows of the windows should not change light transmission when exposed to ionizing radiation from background cosmic radiation and cosmic radiation, including as a result of solar flares. The interaction of electromagnetic radiation from the Sun and cosmic rays with glass is generally a complex phenomenon. Absorption of radiation by glass can lead to the formation of so-called “color centers,” that is, a decrease in the initial light transmission, and also cause luminescence, since part of the absorbed energy can immediately be released in the form of light quanta. The luminescence of the glass creates an additional background, which reduces the image contrast, increases the noise-to-signal ratio and can make the normal functioning of the equipment impossible. Therefore, glass used in optical windows must have, along with high radiation-optical stability, a low level of luminescence. The magnitude of luminescence intensity is no less important for optical glasses operating under the influence of radiation than color resistance.
The window of the Soviet spacecraft Zond-8 (photo: Sergei Andreev) Among the factors of space flight, one of the most dangerous for windows is micrometeor impact. This leads to a rapid decrease in the strength of the glass. Its optical characteristics also deteriorate. After the first year of flight, craters and scratches reaching one and a half millimeters are found on the external surfaces of long-term orbital stations. While most of the surface can be shielded from meteoric and man-made particles, the windows cannot be protected this way. To a certain extent, lens hoods, sometimes installed on the windows through which, for example, on-board cameras operate, help. On the first American orbital station, Skylab, it was assumed that the windows would be partially shielded by structural elements. But, of course, the most radical and reliable solution is to cover the “orbital” windows from the outside with controllable covers. This solution was applied, in particular, at the second-generation Soviet orbital station Salyut-7.
There is more and more “garbage” in orbit. On one of the Shuttle flights, something clearly man-made left a rather noticeable pothole-crater on one of the windows. The glass survived, but who knows what might come next time?.. This, by the way, is one of the reasons for the serious concern of the “space community” about the problems of space debris. In our country, the problems of micrometeorite impact on the structural elements of spacecraft, including windows, are actively studied, in particular, by professor of the Samara State Aerospace University L.G. Lukashev.
Valery Polyakov meets on his way to dock with Discovery World. The tilted porthole cover is clearly visible. The windows of the descent vehicles operate in even more difficult conditions. When descending into the atmosphere, they find themselves in a cloud of high-temperature plasma. In addition to the pressure from inside the compartment, external pressure acts on the window during descent. And then comes the landing - often on snow, sometimes in water. At the same time, the glass cools sharply. Therefore, special attention is paid to issues of strength here.
“The simplicity of the porthole is an apparent phenomenon. Some opticians say that creating a flat illuminator is a more difficult task than making a spherical lens, since building a “precise infinity” mechanism is much more difficult than a mechanism with a finite radius, that is, a spherical surface. And yet, there have never been any problems with the windows,” - this is probably the best assessment for the spacecraft unit, especially if it came from the lips of Georgy Fomin, in the recent past - First Deputy General Designer of the State Scientific Research and Production Space Center "TsSKB - Progress".
WE ARE ALL UNDER THE "DOME" OF EUROPE
Not so long ago - on February 8, 2010, after the Shuttle flight STS-130 - an observation dome appeared on the International Space Station, consisting of several large quadrangular windows and a round eight-hundred-millimeter window.
Micrometeorite damage on the Space Shuttle window (photo: NASA) The Cupola module is designed for Earth observations and operation with a manipulator. It was developed by the European concern Thales Alenia Space, and was built by Italian mechanical engineers in Turin.
Thus, today the Europeans hold the record - such large windows have never been put into orbit either in the USA or in Russia. The developers of various “space hotels” of the future also talk about huge windows, insisting on their special significance for future space tourists. So “window construction” has a great future, and windows continue to be one of the key elements of manned and unmanned spacecraft.
“The view of the Cupola “Dome” observation module is a really cool thing! When you look at the Earth from the porthole, it’s like looking through an embrasure. And in the “dome” there is a 360-degree view, you can see everything! The Earth from here looks like a map, yes, more In all, it resembles a geographical map. You can see how the sun goes away, how it rises, how the night approaches... You look at all this beauty with some kind of freezing inside.”
A little food for thought.
Before reading about the American “space” tin can Gemini, I especially pay attention to the ablative protection - a thick layer of “coating” that burns during descent so that the spacecraft itself does not burn, much like the evaporation of boiling water in a kettle/samovar protects it from damage for the time being. On Soviet descent vehicles, the thickness of this layer was measured in centimeters, and the mass - in hundreds of kilograms (too lazy to Google - almost up to one and a half tons). See the completely burnt declared Gagarin Vostok-1:
and one of the modern Soyuz-TMA with a space tourist:
For a person for whom the studio nature of NASA's manned flights to the Moon is already quite obvious, the question arises: when exactly was it decided that the entire Apollo program would go through Hollywood? Kubrick’s space epic didn’t start out of nowhere: Von Braun was breathing like that, breathing like that, like he was seriously sculpting something, trying... And it ended in complete crap: they sent him to collect meteorites in Antarctica and into some completely incomprehensible inglorious retirement. Why? At what point, in what year did the Great Insight come that taking beautiful photos in the studio would be a little easier than flying to the moon? Let's figure it out.
Before Apollo there were only low-orbit flights - Mercury, Gemini. Are they at least fake?
Well, now let's see something. Let's say Gemini three is the first manned flight under the Gemini program, as future fellow prisoners from NASA unanimously claim. 1965, almost five hours of flight.
"Gemini was the first American ship manufactured using a controlled descent system for the descent vehicle (crew compartment). The shape of the descent vehicle was made in the form of a headlight. Entry into the Earth's atmosphere was carried out bottom first, and thanks to the shifted center of mass relative to the longitudinal axis, the flight atmosphere took place with a constant angle of attack. The controlled flight was carried out due to the rotation of the descent vehicle along the roll angle. The descent vehicle of the Gemini spacecraft was two-seater, which made it possible to perform a spacewalk. At the same time, the entire atmosphere of the astronaut cabin, consisting of oxygen, was vented into space. after closing the hatch, it was restored due to the stored oxygen in the cylinders."
Now let’s go to the NASA website and look for what the hell this was all about:
In the picture, the stump is clear, everything is beautiful. But upon closer examination of photographs of real devices, questions arise:
No, excuse me, no fakes or “training mock-ups” - here’s a real vehicle after the descent, charred, with astronomers Armstrong and Scott inside, after splashdown:
And here it is, as if in space:
Wonderful crap. Beautiful, like a brand new galvanized bucket. Here's how its casing is arranged:
Gemini skin fastening
Do they want to say that these little tins with screws and washers could withstand the flow of air at least at the first cosmic speed?
Say, at 7000 m/sec? The speed of modern aircraft, if anything, is about 200 m/sec. Well, OK, when landing the ship fell bottom first, the bottom there is more massive - but when it takes off and enters orbit, it flies tins forward - and without any protective fairings, like the start is clearly visible:
You see - the tin stands without any fairing. Moreover, her hatches have glass portholes that look straight ahead. Yes, yes - forward to an air flow of 7000 m/sec. It's already funny for engineers, yes. The strategic reconnaissance aircraft SR-71 flies at a speed of 900 m/sec - and it has the most serious problem with the glass frontal blocks of the cockpit, so that they do not fall apart and burst from overheating, a monstrous glass sandwich is made, through which jet fuel is pumped to power the engines . And this is 900 m/sec. It’s hard to imagine what can withstand 7000 m/sec of oncoming flow.
Here you can see this porthole - in the hatch, next to which stands a horseradish with glasses:
Gemini after splashdown, on the deck of the ship:
By the way, it is very typical that NASA photographs were carefully selected so that the porthole was not visible, and the Gemini ships in museums are without hatches at all. But here, in a blurry photo supposedly from space, the porthole is visible on the open hatch:
: Pindos fell into space
No ablative protection? Big deal. In total, the air flow speed is up to 6-7 km/sec, and the temperature is up to 11000° Celsius (and for a short time, much more). Bullshit. Galvanization will hold up. It is covered with a super protective layer that can withstand temperatures up to 3000°C. What are you saying? The Soviet descent vehicles had a protective layer of up to 8 cm, and even then it burned up in the plasma? Why are these scoops so bad? We have nanotechnology. Millimeter coating, but holds better than theirs - 8 cm.
Well, the fact that we then multiplied such a wonderful, simple and excellently proven design by zero and began to sculpt ablative protection and heat shields for Apollo is difficult to explain, but we’ll come up with something.
Not the slightest sign of the screws locking? Well, the fact that there will be wild vibration is nothing particularly scary here. Well, the fastening will loosen, washers and sheathing sheets will begin to dangle and rattle... And if the edge gets stuck, the entire sheathing may be torn off - well, yes, it may well be, so what? They flew off, they tell you in English: they flew off! And all is well! Maybe in those years it was generally fashionable for hypersonics to seat propellers on office glue.
The washers are of such a huge diameter that it’s funny? Slightly tighten the washer with the screw - its edges will rise and the air flow along with the screws themselves, which the M5 approximately pulls out? And to hell with them. Maybe it will work out. The Lunar Chicken Coop over there in the neighboring studio was held together with Cosmic Scotch tape - and nothing happened, people grabbed it.
Recessed to improve aerodynamics? What kind of secret? We don’t know, we don’t know... Stupid? Why are we stupid? We're all like that here at NASA.
Half the screws weren't screwed in yet? So they still won’t be able to hold anything under such loads. And then, we reduced the mass of the ship. You can't screw in a couple of thousand - and the carrying capacity has already increased. And in general, your words are offensive - maybe we’ll have time to complete them just before the flight! You’re finding fault, but in fact you need to praise!
I would especially like to praise these piano hinges for sealed hatches:
The hatches open outwards. It is not difficult to calculate their area and the force that will act on them from the atmosphere in this apparatus - and there supposedly was an atmosphere with a pressure of 0.3 kg/cm. The hatch has an area of about a square meter, 10000 sq. cm * 0.3 = 3000 kg, three tons will put pressure on the hatch from the inside. Bullshit, the piano hinges will hold up, bggggh.
By the way, the same photo shows that there is no additional fastening of the hatch on the hinge side, and that the hatch is sealed with a creepy, unscientific seal, similar to the seal on a refrigerator door. Trust me - it looks funny. The Russians make the hatches of their descent vehicles plug-in from the inside - the pressure presses them against the rubber seal and ensures tightness. The Americans use a stupid design, potentially prone to etching and leaks. However, after the screws and washers, this is just a small thing.
So this bucket did not fly into space. More precisely, maybe it was launched, but in principle it could not return to earth from space with living astronomers inside.
It turns out that Hollywood at NASA began much earlier than the manned Apollo missions.
