Why not fly into space straight from a normal runway at the airport? The Skylon space plane project seeks to meet this ambition and jump over some technical hurdles along the way
Amber dew Galileo
The dream of flying into space using a plane that would take off from a normal runway at an airport, without the need for rocket boosters, and that could be reused a very large number of times, accompanied humanity even before the first satellite was launched in 1957.
Many technological ventures, private and governmental, have gone up and down and even today, 50 years after the first man's flight into space, there is still no tool of this kind, neither for launching humans nor for launching satellites.
Meet the Skylon
An interesting project that is being built in recent years is the Skylon space plane (Skylon, so called because of its resemblance to a steel tower with the same name and an unusual shape, thin and aerodynamic, which was erected in London in 1951 and was destroyed a year later). The aircraft is being developed by Reaction Engines.
The Skylon space plane will be equipped with rocket engines that can also use oxygen from the atmosphere, and in this way Skylon will be a single-stage space launch vehicle. Skylon is designed for a large number of space flights, and it will be able to place satellites weighing up to 15 tons on each space flight.
Much of the knowledge needed to build the space plane was drawn from a British venture to build a space plane, HOTOL, which was conducted during the eighties of the 20th century, and was cancelled. The tool's designers declare its ability to fly into space and back 200 times, and to lower the launch price per kilogram by more than an order of magnitude, compared to what is currently practiced using different launchers.
The Skylon space plane is an aircraft powered by jet engines that change their mode of operation while in flight and become rocket engines powered by liquid fuel (and not based on atmospheric oxygen). The vehicle will use liquid hydrogen to propel it both as a jet plane and as a rocket-propelled vehicle.
When flying in the atmosphere, it will use the oxygen in the air (jet propulsion), and when climbing into space, the vehicle will switch to using liquid oxygen stored in its tanks (rocket propulsion). The Skylon space plane will be able to climb to a height of 26 km and reach a speed of Mach 5.4 with the power of the hydrogen-fed jet engines, before their mode of operation changes to pure rocket propulsion.
When the vessel is in orbit around the Earth, the cargo compartment doors will be opened, and the cargo will be launched into space. Cargoes that could be launched using Skylon include various types of satellites, equipment and supplies for space stations and even manned spacecraft (although this destination is, according to the tool's developers, in the very distant future).
The structure of the space plane
Skylon will be built mostly from carbon fibers that will give it great strength at a low weight compared to metals. Certain parts of the space plane, which require carrying a lot of weight (the connections between the wings and the engines for example), will be built from titanium alloys.
Skylon's fuel tanks will be constructed of aluminum, and insulating materials will be installed inside to insulate it from external heat that will be created due to friction with the atmosphere at high speeds during the flight into space and during the return to Earth.
The outer parts of Skylon will be coated with a thermal protection system based on ceramic compounds, somewhat reminiscent of the special insulation tiles that covered the space shuttle of the United States. The latest Skylon design (model known as C2) is of an 82-meter-long aircraft with a diameter of 6.3 meters.
The Skylon has a central delta wing, with a 25.4 meter boom, at both ends of which its large engines will be installed. Skylon's enormous dimensions stem from the need to contain large amounts of liquid hydrogen - the vehicle's fuel, both as an airplane and as a spacecraft.
Skylon after landing at the airport
Propulsion method: from jet engines to rocket engines
The Skylon space plane is designed to use a unique propulsion method, which has not yet matured for operational use: jet engines that burn hydrogen and have extremely high thrust that "breathe" atmospheric oxygen, which can "change their skin" and become rocket engines that use liquid oxygen.
This process is reversible and thus, when a Skylon comes to land at an airport, it will not glide to the ground without propulsion (like the space shuttles of the United States), but will use jet propulsion. Skylon's unique engine uses a technology called an integrated circuit, in which the air fed into it undergoes significant cooling and turns into a liquid, and is mixed with the liquid hydrogen that serves as its fuel.
The engine is called SABER (an acronym for Synergistic Air Breathing Rocket Engine) and is an advanced development of an engine invented by British engineers in the eighties of the 20th century, called LACE (an acronym for Liquid Air Cycled Engine). The development of Skylon's engine is funded, in large part, by the European Space Agency, although the Skylon project is not part of its operations.
As mentioned above, Skylon's unique jet engines burn liquid hydrogen. These engines can change how they operate in flight; The vessel's large air intakes will be closed and the liquid oxygen supply system will begin to flow it into the combustion chamber in a manner similar to a normal cryogenic rocket engine (a cryogenic engine is an engine that operates using extremely cold liquid fuels - at temperatures close to minus 200 degrees Celsius).
The biggest technical challenge of the engine design is in operating it as a jet engine, and not as a rocket engine. Cooling systems of enormous dimensions and working with great power are needed to turn extremely high temperature air (the air that the engine sucks in when flying at speeds above Mach five) into very cold air. Until now, the operation of the cooling systems has been demonstrated experimentally and on a small scale. The transition to a full-size working engine will require many resources and additional experiments.
Additional applications
The people of the company that develops Skylon presented on their website, as well as at scientific conferences around the world, the possibility of building a large passenger plane in the future that would use Skylon's unique engine technologies. This plane will dwarf today's largest passenger plane, the Airbus A-380, and if it is ever built, it will require many infrastructural changes in airports that want to benefit from its services.
Meanwhile, the dream of the future passenger space plane is so far from its realization that it seems to be on the horizon of science fiction. It should be remembered that the necessary funding to complete a flying model of Skylon has not yet been obtained either.
to the website of the company that develops Skylon
The Skylon user guide
The author is the head of the Center for Space Research, the Fisher Institute for Strategic Air and Space Research, and the chairman of the Israel Space Association
14 תגובות
Spaceshiptwo takes off in a field on a plane and is released at an altitude of 12 km, spaceshipthree is designed to be carried by the largest plane ever built, with a payload capacity of up to 100 tons, I think the British are not aware of what they are doing in the American civilian space field
: )
As far as I know SpaceShipTwo launches into space from the air and not from the ground,
Is its launch cost considered high?
The main thing here is to continue investing budgets, the aspiration to space is part of research and development on scientific issues.
This should be a global trend.
Even in Israel we need to invest in these issues, even if they are not directly related to security but only to pure science...
Of course, we shouldn't forget those who were killed during the landing, like if I'm not mistaken, four Russian cosmonauts in the seventies (three in one flight and one more in another flight), and the Columbia disaster.
In April 1967, cosmonaut Vladimir Mikhailovich Komarov was killed, after he failed to open his emergency parachute during the landing of the spacecraft. In June 1971, three more Russian cosmonauts were killed, when the spacecraft they were flying into space returned to Earth.
My father, the 10 people should be perfected in relation to how many people were launched into space. According to Wikipedia, the number of people who have been launched into space (or experienced a launch that poses the same risk) is 523. Of these, 10 were killed. This is 1.9 percent of the people.
You have to calculate this percentage in the amount of people killed by traveling in a car, traveling on trains, flying in an airplane and flying in a hot air balloon to know how dangerous it is to fly into space.
However, even here it is not accurate, since the amount of money invested in road safety, car safety and flight safety must also be calculated. And all this, during the last 50 years.
Avi,
So we'll start with small satellites and progress from there.
Not sure I understood the comparison to the number of deaths from smoking. I am trying to compare launch prices between ground and air, human life is only one of the factors.
Too expensive for a large satellite and certainly for manned flight. Still reasonable and considered for small satellites.
Besides, ten people is a smaller number than the number of people who die every second from smoking.
Tal,
Even one disaster is too many. Challenger in 1986 and Apollo 1 in 1967 claimed ten lives. In the history of the satellite launcher in Kazakhstan, there are no known disasters, but there were many failures that cost a huge fortune.
My father's words imply that launching by plane is expensive but possible, so we have a challenge.
What about launching from the stratosphere, at an altitude of 50 km above the earth, when most of the atmosphere no longer exists?
Weather balloons that reach these heights can already be built today, I am sure that if a few billions are invested in the development of airships that will reach this height, this will be resolved within ten years. It is even possible to build a stratospheric launch station, or a kind of flying launcher carrier that will stay at that altitude for months and years. It will even be possible to anchor it or move it to the equator or other places and even then it will be above the height of most of the weather.
I published an article on this subject in 2004. The name of the article is "Shuttles to the Moon".
https://www.hayadan.org.il/shuttle-to-the-moon-15090/
I will add to Tal's words that launching from the air is relevant, even though it is expensive and probably not practical except for military purposes where a spy satellite needs to be immediately launched into space and there is no time to prepare for its launch. Our Air Force has also been talking for several years about launching satellites from space, and Rafael is also developing from such a launcher.
Yuval, the history of human space travel is not really "full" of disaster stories as you say. Carrying a launcher into space by plane has been debated for many decades, and many ventures started with great fanfare and stalled due to economic or technological reasons.
The release height of an airborne launcher would be about ten km and the speed Mach 0.8 - I would not define these conditions as "high altitude and speed".
In the meantime, until this is applicable, why don't we use large aircraft as launchers?
The current launch method is not safe, and the short history of human space travel is full of stories of disasters that happened on the ground or in the atmosphere. Conventional aviation is developed, advanced and infinitely safer. A large decoy plane can carry a shuttle on its back and give it good starting conditions at many altitudes and speeds.
The problem that my proposal does not solve is the low safety during the shuttle's return to the atmosphere. But that deserves an extended discussion elsewhere.