Fully reusable aerospace system from existing technologies
The word "astronautics" from the time of Korolev and Gagarin means huge spaceports and disposable rockets. Well, not always disposable - but even the reusable rocket stages of Elon Mask should be brought in every time, assembled in a special workshop, installed on a special launch pad, refueled, checked - and only then launched. It is not surprising that astronautics is a very expensive pleasure and the massive industrial development of space resources even now seems like a vague prospect for the near future.
What can replace missiles? Reusable aerospace system. This idea is not new: after the appearance of the An-225 Mriya aircraft, many aerospace systems were designed on its basis, as can be learned from the memoirs of Anatoly Vovnyanko , who participated in its creation. The most interesting of them is MAKS-M:
The most important advantage of this option is full reusability. The aircraft acts as the first stage. This eliminates the need for a special cosmodrome - it can be any airport that can take An-225. The aircraft itself can carry out tens of thousands of spacecraft launches throughout its entire life cycle.
The spaceplane, designed for use with the An-225, can weigh up to 275 tons. According to preliminary calculations , a fully reusable version can bring into low Earth orbit from 5.5 tons at a latitude of 51 ° to 7 tons at the equator. In case of incomplete loading, you can launch a spaceplane near the launch aerodrome (for example, on the territory of Ukraine or over the Black Sea), and if you need to bring exactly 7 tons into orbit, the plane can fly to the equator and launch already there.
The separation of the aircraft and the spaceplane occurs at an altitude of 10 km and a speed of 236 m / s (850 km / h). To smoothly separate the heavy spaceplane located on the back of the aircraft, you need to create a small negative overload. A plane for this makes something like this “slide”:
and on it the spaceplane is separated. After that, the plane returns to the airfield, and the spaceplane, having an initial speed, begins horizontal acceleration. It is horizontal: the spaceplane has aerodynamic quality, and the greater the horizontal speed in the atmosphere, the greater the lifting force. In addition, in order to enter orbit, it is necessary to develop a horizontal speed of 8 km / s. Kinetic energy for speed:
But at an altitude of 10 km you cannot enter orbit: the atmosphere is in the way. For a stable low orbit, you need to gain 200 km. Potential energy for height (neglecting the gradient of g over height, since it is important for us only to estimate the order):
Let us evaluate the ratio of the energy of horizontal acceleration and vertical rise:
If we substitute the numbers, we get that the energy for climbing 200 km is about 16 times less than for climbing a horizontal speed of 8 km / s. So what matters most is horizontal acceleration, in which aerodynamics will do most of the lifting work.
On a spacecraft, you can put the usual, long-developed and produced by the rocket industry, oxygen-kerosene rocket engines. At the same time, the thrust of the engines is much less than in the case of a conventional vertical take-off rocket: there is no direct need to overcome gravity, the spaceplane has aerodynamic quality and is supported by lift in the air. Again, the greater the horizontal speed (which you need to pick up already) - the stronger the atmosphere will push the spaceplane into space.
Once in space, the spaceplane leaves in orbit a container with cargo. Further in outer space, it is best to haul cargo in orbital tugs at nuclear reactors with a nuclear reactor . With a thrust of the order of 1-2 Newton, suitable only for acceleration in zero gravity and space vacuum, they provide a very high specific impulse. If a chemical engine gives a jet of up to 5 km / s, then an electroreactive accelerator can accelerate ions to 300 km / s - that is, 60 times more efficient. However, what to do in space itself is a topic for a separate article, and not one.
After completing the task, the spaceplane leaves orbit and returns to the atmosphere. It is already empty and relatively light, but still has aerodynamic quality. This means that the descent from orbit will be much smoother than the ballistic descent of conventional descent vehicles. At the same time, the spaceplane should have a special shape for a smoother descent than the shuttles and Buran. This will reduce (if not eliminate) the need for thermal protection - and related consumables and maintenance.
The spaceplane can land at the airport, from which it will be its next flight into space. There, undergo maintenance and loading of cargo. After that, an empty spaceplane (that is, weighing within 100 tons) is loaded with an autocrane onto the back of the An-225, refuel with the plane - and on a new flight. Theoretically, one An-225 can launch on a space plane every 4-6 hours, or even more often. That is, 20-30 tons per orbit per day, and so every day. When the spaceplanes begin to fly steadily into orbit every few hours, one can already confidently talk about industrial space exploration.
Such a startup frequency and such an intensive operating mode are possible only if one-time components such as booster units or an external fuel tank are completely eliminated. It is also necessary to minimize consumables, ideally so that each time only kerosene and liquid oxygen are consumed. The described aerospace system uses the same aerodromes and even the same kerosene as conventional aviation. Any airfield capable of receiving An-225 can easily become a spaceport. There are differences from conventional aviation, but they fit well into the framework of the aerodrome infrastructure: loading a space plan on the An-225 with a truck crane, refueling with liquid oxygen and maintaining the space plan in airfield hangars, which, again, should not be much more complicated than an airplane.
The An-225 airplane has existed in a flying copy for 30 years. In addition, there is another unfinished instance that can be completed specifically for the needs of the aerospace program. There is no ready-made space plan yet - and this is even good, since it will allow you to design from scratch a new design that is optimized as much as possible for an air launch from a carrier aircraft and intensive operation with a minimum of consumables and maintenance. Most of the components necessary for such an aerospace program can be produced within Ukraine.
In addition to space flights, another no less attractive prospect opens up: suborbital airlines. After testing the technology at orbital launches, it will be possible to apply it already for ultra-high-speed passenger and mail transportation. A spaceplane flight along a suborbital trajectory to anywhere in the world will take no more than an hour. Do you want to fly from Europe to South America or Australia in an hour of zero gravity?
At section 1, the spaceplane accelerates on its engines to a speed sufficient to enter the suborbital trajectory. At Section 2, it flies through space in zero gravity, which passengers feel. At section 3, aerodynamic drag occurs, after which landing occurs at the target airport.
A spacecraft compatible with the An-225 can accommodate up to 60 passengers during suborbital flight. If at the same time it is possible to achieve “airplane” simplicity of operating the aerospace system, tickets will cost slightly more than conventional aircraft: in 15 hours, instead of the usual long-distance flight with passengers, the An-225 can manage to launch several suborbital space planes, carrying a commensurate number of passengers. The only question is the speed of pre-launch operations, which can be gradually increased (of course, not to the detriment of security). There should be another An-225 at the destination, launching space planes on the return flight.
Such a system will be easy to deploy and collapse at any airport in the world: it is enough on the An-225 itself to bring in a truck crane for loading the space plan and portable equipment for oxygen liquefaction, which is used to fill the space plane. The expensive, complex and long-term construction of stationary infrastructure (as at spaceports for conventional missiles) is not needed.
A fully reusable aerospace system can not only open the era of industrial space exploration, but also make it possible to fly to the farthest point of the Earth in an hour.
UPD: in the comments mentioned a partially reusable version of the MAX with an external fuel tank. The system with an external tank, according to calculations, will output 19.5 tons at the equator, and fully reusable - 7 tons. So what? During a more complex prelaunch preparation of a system with an external tank, you can just have time to prepare and launch a reusable spacecraft 3 or more times. Which, incidentally, has a much larger cargo compartment, that is, it is possible to display more oversized cargo.
It was also discussed that a subsonic carrier aircraft would produce very little initial velocity. What to bring wings into space is a decrease in useful mass. But the key advantage of the described system is not in the initial speed of the spaceplane, and not in the output mass. The key advantage is almost aircraft simplicity and speed of preparation for launch, minimizing the complexity of the necessary equipment . Again, instead of a single launch of a single or partially reusable medium, it is possible to carry out several starts of a reusable system. By minimizing the cost of each start, it will be more profitable.
UPD2: Liquefied methane may be a more suitable fuel for a space plane than kerosene. The cryogenics of liquid methane and oxygen are about the same, so this will only slightly complicate the system. It is best to deliver fuel by rail, laying the rails directly to the airfield’s gas station.
UPD3: the comments dealt with the complexity of servicing a spaceplane and the Shuttle was cited as an example of the impossibility of reducing it. However, the Shuttle had a starting mass of 2030 tons, while it had a disposable external tank and conditionally reusable boosters that still needed to be caught in the ocean, brought and refueled. The system with the Shuttle required assembly in a special workshop and a launch pad with export to it. And the assembly of the described system comes down to loading the spaceplane onto the back of the An-225 with a crane.
As for the difficulty in servicing the Shuttle itself, the main problem is engines with a thrust of 541 tons. On a horizontal space launch plan with a mass of 275 tons, their thrust can be significantly less. Perhaps even less than the mass of the spaceplane, since the work to overcome gravity does the lifting force. Less thrust - less vibration - easier spacecraft maintenance between flights.
UPD4: a spaceplane on an airplane must be submerged by a truck crane.
An empty spaceplane weighs less than 100 tons - and this mass is available even to serial truck cranes. The gyrodynes of the spaceplane itself (designed for turning around its axis in orbit) can help stabilize and rotate the spaceplane during the ascent.
On the back of the An-225 to external mounts there should be a special adapter for mounting spacecraft. In it - “ruts” for the spacecraft landing gear. When the truck crane immerses and releases the space plan, the chassis becomes exactly in the right position, after which additional fastenings are fixed. After the final fixation, refueling and take-off occurs.
What can replace missiles? Reusable aerospace system. This idea is not new: after the appearance of the An-225 Mriya aircraft, many aerospace systems were designed on its basis, as can be learned from the memoirs of Anatoly Vovnyanko , who participated in its creation. The most interesting of them is MAKS-M:
The most important advantage of this option is full reusability. The aircraft acts as the first stage. This eliminates the need for a special cosmodrome - it can be any airport that can take An-225. The aircraft itself can carry out tens of thousands of spacecraft launches throughout its entire life cycle.
The spaceplane, designed for use with the An-225, can weigh up to 275 tons. According to preliminary calculations , a fully reusable version can bring into low Earth orbit from 5.5 tons at a latitude of 51 ° to 7 tons at the equator. In case of incomplete loading, you can launch a spaceplane near the launch aerodrome (for example, on the territory of Ukraine or over the Black Sea), and if you need to bring exactly 7 tons into orbit, the plane can fly to the equator and launch already there.
The separation of the aircraft and the spaceplane occurs at an altitude of 10 km and a speed of 236 m / s (850 km / h). To smoothly separate the heavy spaceplane located on the back of the aircraft, you need to create a small negative overload. A plane for this makes something like this “slide”:
and on it the spaceplane is separated. After that, the plane returns to the airfield, and the spaceplane, having an initial speed, begins horizontal acceleration. It is horizontal: the spaceplane has aerodynamic quality, and the greater the horizontal speed in the atmosphere, the greater the lifting force. In addition, in order to enter orbit, it is necessary to develop a horizontal speed of 8 km / s. Kinetic energy for speed:
But at an altitude of 10 km you cannot enter orbit: the atmosphere is in the way. For a stable low orbit, you need to gain 200 km. Potential energy for height (neglecting the gradient of g over height, since it is important for us only to estimate the order):
Let us evaluate the ratio of the energy of horizontal acceleration and vertical rise:
If we substitute the numbers, we get that the energy for climbing 200 km is about 16 times less than for climbing a horizontal speed of 8 km / s. So what matters most is horizontal acceleration, in which aerodynamics will do most of the lifting work.
On a spacecraft, you can put the usual, long-developed and produced by the rocket industry, oxygen-kerosene rocket engines. At the same time, the thrust of the engines is much less than in the case of a conventional vertical take-off rocket: there is no direct need to overcome gravity, the spaceplane has aerodynamic quality and is supported by lift in the air. Again, the greater the horizontal speed (which you need to pick up already) - the stronger the atmosphere will push the spaceplane into space.
Once in space, the spaceplane leaves in orbit a container with cargo. Further in outer space, it is best to haul cargo in orbital tugs at nuclear reactors with a nuclear reactor . With a thrust of the order of 1-2 Newton, suitable only for acceleration in zero gravity and space vacuum, they provide a very high specific impulse. If a chemical engine gives a jet of up to 5 km / s, then an electroreactive accelerator can accelerate ions to 300 km / s - that is, 60 times more efficient. However, what to do in space itself is a topic for a separate article, and not one.
After completing the task, the spaceplane leaves orbit and returns to the atmosphere. It is already empty and relatively light, but still has aerodynamic quality. This means that the descent from orbit will be much smoother than the ballistic descent of conventional descent vehicles. At the same time, the spaceplane should have a special shape for a smoother descent than the shuttles and Buran. This will reduce (if not eliminate) the need for thermal protection - and related consumables and maintenance.
The spaceplane can land at the airport, from which it will be its next flight into space. There, undergo maintenance and loading of cargo. After that, an empty spaceplane (that is, weighing within 100 tons) is loaded with an autocrane onto the back of the An-225, refuel with the plane - and on a new flight. Theoretically, one An-225 can launch on a space plane every 4-6 hours, or even more often. That is, 20-30 tons per orbit per day, and so every day. When the spaceplanes begin to fly steadily into orbit every few hours, one can already confidently talk about industrial space exploration.
Such a startup frequency and such an intensive operating mode are possible only if one-time components such as booster units or an external fuel tank are completely eliminated. It is also necessary to minimize consumables, ideally so that each time only kerosene and liquid oxygen are consumed. The described aerospace system uses the same aerodromes and even the same kerosene as conventional aviation. Any airfield capable of receiving An-225 can easily become a spaceport. There are differences from conventional aviation, but they fit well into the framework of the aerodrome infrastructure: loading a space plan on the An-225 with a truck crane, refueling with liquid oxygen and maintaining the space plan in airfield hangars, which, again, should not be much more complicated than an airplane.
The An-225 airplane has existed in a flying copy for 30 years. In addition, there is another unfinished instance that can be completed specifically for the needs of the aerospace program. There is no ready-made space plan yet - and this is even good, since it will allow you to design from scratch a new design that is optimized as much as possible for an air launch from a carrier aircraft and intensive operation with a minimum of consumables and maintenance. Most of the components necessary for such an aerospace program can be produced within Ukraine.
In addition to space flights, another no less attractive prospect opens up: suborbital airlines. After testing the technology at orbital launches, it will be possible to apply it already for ultra-high-speed passenger and mail transportation. A spaceplane flight along a suborbital trajectory to anywhere in the world will take no more than an hour. Do you want to fly from Europe to South America or Australia in an hour of zero gravity?
At section 1, the spaceplane accelerates on its engines to a speed sufficient to enter the suborbital trajectory. At Section 2, it flies through space in zero gravity, which passengers feel. At section 3, aerodynamic drag occurs, after which landing occurs at the target airport.
A spacecraft compatible with the An-225 can accommodate up to 60 passengers during suborbital flight. If at the same time it is possible to achieve “airplane” simplicity of operating the aerospace system, tickets will cost slightly more than conventional aircraft: in 15 hours, instead of the usual long-distance flight with passengers, the An-225 can manage to launch several suborbital space planes, carrying a commensurate number of passengers. The only question is the speed of pre-launch operations, which can be gradually increased (of course, not to the detriment of security). There should be another An-225 at the destination, launching space planes on the return flight.
Such a system will be easy to deploy and collapse at any airport in the world: it is enough on the An-225 itself to bring in a truck crane for loading the space plan and portable equipment for oxygen liquefaction, which is used to fill the space plane. The expensive, complex and long-term construction of stationary infrastructure (as at spaceports for conventional missiles) is not needed.
A fully reusable aerospace system can not only open the era of industrial space exploration, but also make it possible to fly to the farthest point of the Earth in an hour.
UPD: in the comments mentioned a partially reusable version of the MAX with an external fuel tank. The system with an external tank, according to calculations, will output 19.5 tons at the equator, and fully reusable - 7 tons. So what? During a more complex prelaunch preparation of a system with an external tank, you can just have time to prepare and launch a reusable spacecraft 3 or more times. Which, incidentally, has a much larger cargo compartment, that is, it is possible to display more oversized cargo.
It was also discussed that a subsonic carrier aircraft would produce very little initial velocity. What to bring wings into space is a decrease in useful mass. But the key advantage of the described system is not in the initial speed of the spaceplane, and not in the output mass. The key advantage is almost aircraft simplicity and speed of preparation for launch, minimizing the complexity of the necessary equipment . Again, instead of a single launch of a single or partially reusable medium, it is possible to carry out several starts of a reusable system. By minimizing the cost of each start, it will be more profitable.
UPD2: Liquefied methane may be a more suitable fuel for a space plane than kerosene. The cryogenics of liquid methane and oxygen are about the same, so this will only slightly complicate the system. It is best to deliver fuel by rail, laying the rails directly to the airfield’s gas station.
UPD3: the comments dealt with the complexity of servicing a spaceplane and the Shuttle was cited as an example of the impossibility of reducing it. However, the Shuttle had a starting mass of 2030 tons, while it had a disposable external tank and conditionally reusable boosters that still needed to be caught in the ocean, brought and refueled. The system with the Shuttle required assembly in a special workshop and a launch pad with export to it. And the assembly of the described system comes down to loading the spaceplane onto the back of the An-225 with a crane.
As for the difficulty in servicing the Shuttle itself, the main problem is engines with a thrust of 541 tons. On a horizontal space launch plan with a mass of 275 tons, their thrust can be significantly less. Perhaps even less than the mass of the spaceplane, since the work to overcome gravity does the lifting force. Less thrust - less vibration - easier spacecraft maintenance between flights.
UPD4: a spaceplane on an airplane must be submerged by a truck crane.
An empty spaceplane weighs less than 100 tons - and this mass is available even to serial truck cranes. The gyrodynes of the spaceplane itself (designed for turning around its axis in orbit) can help stabilize and rotate the spaceplane during the ascent.
On the back of the An-225 to external mounts there should be a special adapter for mounting spacecraft. In it - “ruts” for the spacecraft landing gear. When the truck crane immerses and releases the space plan, the chassis becomes exactly in the right position, after which additional fastenings are fixed. After the final fixation, refueling and take-off occurs.
All Articles