Launching spacecraft into orbit. Soviet orbital trick. Orbits of artificial earth satellites

Just as seats in a theater provide different perspectives on a performance, different satellite orbits provide perspectives, each with a different purpose. Some appear to hover above a point on the surface, providing a constant view of one side of the Earth, while others circle our planet, passing over many places in a day.

Types of orbits

At what altitude do satellites fly? There are 3 types of near-Earth orbits: high, medium and low. At the highest level, farthest from the surface, as a rule, many weather and some communications satellites are located. Satellites rotating in medium-Earth orbit include navigation and special ones designed to monitor a specific region. Most scientific spacecraft, including NASA's Earth Observing System fleet, are in low orbit.

The speed of their movement depends on the altitude at which satellites fly. As you approach the Earth, gravity becomes stronger and the movement accelerates. For example, NASA's Aqua satellite takes about 99 minutes to orbit our planet at an altitude of about 705 km, while a meteorological device located 35,786 km from the surface takes 23 hours, 56 minutes and 4 seconds. At a distance of 384,403 km from the center of the Earth, the Moon completes one revolution in 28 days.

Aerodynamic paradox

Changing the satellite's altitude also changes its orbital speed. There is a paradox here. If a satellite operator wants to increase its speed, he can't just fire up the engines to speed it up. This will increase the orbit (and altitude), resulting in a decrease in speed. Instead, the engines should be fired in the opposite direction of the satellite's motion, an action that would slow down a moving vehicle on Earth. This action will move it lower, allowing for increased speed.

Orbit characteristics

In addition to altitude, a satellite's path is characterized by eccentricity and inclination. The first relates to the shape of the orbit. A satellite with low eccentricity moves along a trajectory close to circular. An eccentric orbit has the shape of an ellipse. The distance from the spacecraft to the Earth depends on its position.

Inclination is the angle of the orbit relative to the equator. A satellite that orbits directly above the equator has zero inclination. If a spacecraft passes over the northern and south poles(geographical, not magnetic), its inclination is 90°.

All together - height, eccentricity and inclination - determine the movement of the satellite and how the Earth will look from its point of view.

High near-Earth

When the satellite reaches exactly 42,164 km from the center of the Earth (about 36 thousand km from the surface), it enters a zone where its orbit matches the rotation of our planet. Since the craft is moving at the same speed as the Earth, i.e., its orbital period is 24 hours, it appears to remain stationary over a single longitude, although it may drift from north to south. This special high orbit is called geosynchronous.

The satellite moves in a circular orbit directly above the equator (eccentricity and inclination are zero) and remains stationary relative to the Earth. It is always located above the same point on its surface.

The Molniya orbit (inclination 63.4°) is used for observation at high latitudes. Geostationary satellites are tied to the equator, so they are not suitable for far northern or southern regions. This orbit is quite eccentric: the spacecraft moves in an elongated ellipse with the Earth located close to one edge. Because the satellite is accelerated by gravity, it moves very quickly when it is close to our planet. As it moves away, its speed slows down, so it spends more time at the top of its orbit at the edge farthest from Earth, the distance to which can reach 40 thousand km. The orbital period is 12 hours, but the satellite spends about two-thirds of this time over one hemisphere. Like a semi-synchronous orbit, the satellite follows the same path every 24 hours. It is used for communication on far north or south.

Low near-Earth

Most scientific satellites, many meteorological satellites, and the space station are in nearly circular low-Earth orbit. Their tilt depends on what they are monitoring. TRMM was launched to monitor rainfall in the tropics, so it has a relatively low inclination (35°), remaining close to the equator.

Many of NASA's observing system satellites have a near-polar, high-inclination orbit. The spacecraft moves around the Earth from pole to pole with a period of 99 minutes. Half of the time it passes over the day side of our planet, and at the pole it turns to the night side.

As the satellite moves, the Earth rotates underneath it. By the time the vehicle moves to the illuminated area, it is over the area adjacent to the zone of its last orbit. In a 24-hour period, the polar satellites cover most of the Earth twice: once during the day and once at night.

Sun-synchronous orbit

Just as geosynchronous satellites must be located above the equator, which allows them to remain above one point, polar orbiting satellites have the ability to remain at the same time. Their orbit is sun-synchronous - when the spacecraft crosses the equator, local solar time is always the same. For example, the Terra satellite always crosses it over Brazil at 10:30 am. The next crossing 99 minutes later over Ecuador or Colombia also occurs at 10:30 local time.

A sun-synchronous orbit is essential for science because it allows sunlight to remain on the Earth's surface, although it will vary depending on the season. This consistency means scientists can compare images of our planet from the same season over several years without worrying about too big jumps in light, which could create the illusion of change. Without a sun-synchronous orbit, it would be difficult to track them over time and collect the information needed to study climate change.

The satellite's path here is very limited. If it is at an altitude of 100 km, the orbit should have an inclination of 96°. Any deviation will be unacceptable. Because atmospheric resistance and the gravitational force of the Sun and Moon change the spacecraft's orbit, it must be adjusted regularly.

Injection into orbit: launch

Launching a satellite requires energy, the amount of which depends on the location of the launch site, the height and inclination of the future trajectory of its movement. Getting to a distant orbit requires more energy. Satellites with a significant inclination (for example, polar ones) are more energy-intensive than those circling the equator. Insertion into a low-inclination orbit is aided by the rotation of the Earth. moves at an angle of 51.6397°. This is necessary to make it easier for space shuttles and Russian rockets to reach it. The height of the ISS is 337-430 km. Polar satellites, on the other hand, do not receive any assistance from the Earth's momentum, so they require more energy to rise the same distance.

Adjustment

Once a satellite is launched, efforts must be made to keep it in a certain orbit. Because the Earth is not a perfect sphere, its gravity is stronger in some places. This unevenness, along with the gravitational pull of the Sun, Moon and Jupiter (the most massive planet solar system), changes the inclination of the orbit. Throughout their lifetime, the GOES satellites have been adjusted three or four times. NASA's low-orbiting vehicles must adjust their inclination annually.

In addition, near-Earth satellites are affected by the atmosphere. The uppermost layers, although quite rarefied, exert a strong enough resistance to pull them closer to the Earth. The action of gravity leads to the acceleration of satellites. Over time, they burn up, spiraling lower and faster into the atmosphere, or fall to Earth.

Atmospheric drag is stronger when the Sun is active. Just like the air in hot-air balloon expands and rises when heated, the atmosphere rises and expands when the Sun gives it additional energy. Thin layers of the atmosphere rise, and denser layers take their place. Therefore, satellites orbiting the Earth must change their position approximately four times a year to compensate for atmospheric drag. When solar activity is at its maximum, the position of the device has to be adjusted every 2-3 weeks.

Space debris

The third reason forcing a change in orbit is space debris. One of Iridium's communications satellites collided with a non-functioning Russian spacecraft. They crashed, creating a cloud of debris consisting of more than 2,500 pieces. Each element was added to the database, which today includes over 18,000 objects of man-made origin.

NASA carefully monitors everything that may be in the path of satellites, since orbits have already had to be changed several times due to space debris.

Engineers monitor the position of space debris and satellites that could interfere with the movement and carefully plan evasive maneuvers as necessary. The same team plans and executes maneuvers to adjust the satellite's tilt and altitude.

To launch two spacecraft, a single-launch scheme is being considered using the SOYUZ LV and FREGAT LV. Figure 10 shows a diagram of the launch of the first spacecraft into a working orbit. The launch vehicle launches the warhead (SC and RB) into a circular reference orbit of an artificial satellite at an altitude of 200 km. On the first orbit of the reference orbit, the first RB is turned on (

V 1), as a result of which the head part is transferred to the first transfer orbit, in which the apogee altitude is 350 km, and the perigee argument differs from the perigee argument of the working orbit of the first type by 180°.

In this orbit, in the apogee region, the second activation of the RB takes place

(V 2) and the warhead is transferred to the second transfer orbit. The apogee height of this orbit is equal to the apogee height of the working orbit of the first type. After this, the first spacecraft launched into a working orbit of the first type is separated from the upper stage. Further maneuvers of this spacecraft are carried out using its own propulsion system. A detailed description of this stage is given in section 3.8.

The RB with the remaining second spacecraft continues to form an equatorial working orbit. Figure 11 schematically shows this stage of formation of the working orbit of an equatorial spacecraft. To do this, in the area of the descending node of the second transfer orbit, the third switching on of the RB remote control is carried out and the head part is transferred to the fourth transfer orbit, which is located almost in the plane of the Earth's equator. After this, the second spacecraft, launched into a working near-equatorial orbit, is separated from the upper stage. Further maneuvers of this spacecraft are carried out using

own propulsion system. A detailed description of this stage is given in section 3

.8. This completes the tasks of the accelerating unit.

The energy costs of the Fregat RB and the spacecraft propulsion system during the formation of working orbits are summarized in Table 5.

Table 5

	Purpose	Value, m/s
	Formation of the first transfer orbit
	Formation of the second transfer orbit
	Formation of the third transfer orbit
	Total costs of RB “Fregat”
	Formation of the working orbit of the 1st spacecraft (PS of the 1st spacecraft)
	Formation of the working orbit of the 2nd spacecraft (PS of the 2nd spacecraft)
	Corrections for phasing of the 1st and 2nd spacecraft	20.0 for each spacecraft
	Corrections of working orbits of the 1st and 2nd spacecraft (approximately once a month for 3 years)	110.0 for each spacecraft

To launch a spacecraft into orbit, the launch vehicle must inform it completely certain speed, both in magnitude and direction at given coordinates of the end of the flight. This is ensured by the launch program, the flight of which occurs when the control elements act on the launch vehicle. The path traversed by the launch vehicle when launching a spacecraft into orbit is called the flight path (Fig. 3.14) and is characterized by active and passive sections. The active phase of the flight is the flight of the stages of the launch vehicle with the engine running, the passive phase is the flight of the spent rocket units after their separation from the launch vehicle. It is also possible for the launch vehicle to fly in the so-called pulse mode, that is, with interruptions in engine operation.

Rice. 3.14. Launch vehicle trajectory:

1 - Earth; 2 - vertical flight segment; 3 - active phase of the first stage flight;

4 - active phase of the 2nd stage flight; 5 - active phase of stage III flight;

6 - spacecraft orbit; 7 - passive flight phase of the second stage rocket unit;

8 - passive flight phase of the first stage rocket unit; 9 - local horizon;

10 - direction of the earth's radius

The launch vehicle, starting vertically, then enters a curved section of the flight path, which ensures a gradual decrease in the angle of inclination of its axis relative to the local horizon. To reduce the speed loss of the launch vehicle from aerodynamic drag, it is desirable for it to pass through the dense layers of the atmosphere as quickly as possible and to bring its flight path closer to horizontal only after leaving these layers. In dense layers of the atmosphere, the launch vehicle, as a rule, moves along a trajectory close to the trajectory with zero lift, which reduces the loads caused by aerodynamic forces at high angles of attack on its body.

One of the main issues related to the flight trajectory is the question of its optimization, i.e., determining a trajectory along which the optimality criterion (orbit altitude, payload size, etc.) reaches its maximum (minimum) value. In this case, two problems are usually solved: the first is to determine the optimal flight trajectory of the launch vehicle with its known parameters, and the second is to determine the parameters of the launch vehicle with known requirements for its flight trajectory, i.e., the optimal design problem.

As a rule, launch vehicles impart only the first escape velocity to the spacecraft and launch it into either a circular or elliptical orbit. Achieving the second and third cosmic velocities is more profitable due to the energy of the spacecraft itself, starting in this case from the reference orbit of the satellite.

Parameters that determine the final speed of the launch vehicle. In the general case, the movement of a launch vehicle is characterized by a rather complex system of equations (Appazov R.F., Lavrov S., S., Mishin V.P. Ballistics of long-range guided missiles. M., Nauka, 1966), one of which, taking into account only the main forces acting on the launch vehicle in flight can be written in the form

, (3.1)

Where V- speed of the launch vehicle;

τ - flight time;

R- engine thrust;

X- aerodynamic drag force;

m- current mass of the launch vehicle (mass at a given time);

g- acceleration of gravity;

θ - the angle of inclination of the tangent to the flight path relative to the horizon.

To identify the parameters that determine the final speed of the launch vehicle, we will use transformations of equation (3.1), according to which the final speed of the launch vehicle

Where ; (3.3)

; (3.4)

– relative mass of the launch vehicle – dimensionless coefficient characterizing its current mass; m 0 and T– launch and current masses of the launch vehicle, respectively; – midsection load – launch weight per unit area of the maximum cross-section of the launch vehicle; S m – midsection area; and – specific impulse of the rocket engine at sea level and in vacuum, respectively; – dimensionless coefficient characterizing the thrust-to-weight ratio of the launch vehicle; P 0 – starting (at sea level) thrust of the launch vehicle; – speed pressure; V– current speed of the launch vehicle; R 0 – atmospheric pressure at sea level; ρ And R– current density and pressure of the atmosphere at the location of the launch vehicle in this moment time; C X is the dimensionless coefficient of aerodynamic drag force.

From equations (3.2) – (3.5) it follows that the final speed of the launch vehicle is determined by design and energy parameters: relative final mass μ k, specific impulse of the engine and, thrust-to-weight ratio of the launch vehicle, characterized by the value ν 0 , an aerodynamic configuration characterized by the values R m and WITH X, and trajectory parameters (program for changing the angle θ , change in speed pressure q and pressure environment R by flight time). Relative final mass of the launch vehicle

, (3.6)

Where m pg – payload mass; m kon – mass of structural elements of the launch vehicle body and its systems; m then is the mass of fuel residues; m g – mass of charge gases; m 0 – launch vehicle mass.

Magnitude μ k is determined by the perfection of the design of the body, assemblies and systems of the launch vehicle, as well as by the perfection of the engine and fuel system, which determine the amount of fuel residue and the final mass of pressurized gases of the fuel tanks. The perfection of the design of the body, assemblies and systems depends on the skill of the designer, the adopted layout scheme, the development of materials science and the level of loads determined by the degree of optimization of the flight path.

The smaller the value μ Moreover, the higher speed the launch vehicle develops at the end of its flight.

The specific impulse of the engine depends on the type of propulsion system (solid propellant rocket engine, liquid propellant rocket engine, nuclear rocket engine), fuel components (working fluid) and the level of development of engine building. The latter is characterized by the perfection of the engine design (the presence or absence of unproductive losses of fuel components), the perfection of fuel combustion processes and the degree of expansion of combustion products. The higher the engine specific impulse, the longer the launch vehicle's terminal speed.

The thrust-to-weight ratio of the launch vehicle has a dual effect on the value of the final speed. Its increase leads to a decrease in flight time and an increase in the speed of passage of dense layers of the atmosphere (increase in speed pressures), a decrease in costs and energy for overcoming the force of gravity and an increase in overcoming the forces of aerodynamic resistance. At the same time, the loads acting on the launch vehicle body increase, which causes an increase in its final mass. The complex nature of the influence of the thrust-to-weight ratio of a launch vehicle on the value of its final speed for a specific design leads to the need for joint optimization of the parameters of the launch vehicle and its flight trajectory.

The influence of the aerodynamic configuration of the launch vehicle on its final speed is determined by the load on the midsection R m and aerodynamic drag force coefficient WITH X, with the coefficient WITH X is a direct indicator of the perfection of the aerodynamic configuration, and R m - indirect, although more visual. The perfection of the aerodynamic layout of simple layout schemes (monoblock, without a large number of elements protruding above the body contours, with a limited number of engines, etc.) is quite well characterized by the value R m, and the aerodynamic perfection of more complex layout schemes - by the coefficient WITH X. Aerodynamic perfection can be characterized by a dimensionless coefficient

where is the relative mass of the payload at an arbitrary load on the midsection;

μ pg 10,000 – relative payload mass at R m =10,000 kgf/m.

Schemes for launching a spacecraft into orbit.

The speed required to launch a spacecraft into a circular orbit in the central gravitational field of the Earth is determined by the formula:

Where g= 9.81 m/s2 – free fall acceleration; R = 6,371 km - the average radius of the Earth; H is the height of the spacecraft’s orbit above the Earth’s surface.

The value of this speed at H=0 is called the first cosmic speed (~ 7,900 m/s). For a low circular orbit H=200 km (base orbit), the speed of the spacecraft is 7,791 m/s, for a geostationary orbit H=35,809 km – 3,076 m/s.

For elliptical orbits, terminal velocities V uh = 7,900…11,200 m/s. From an energy point of view, the parabolic flight of a spacecraft is characterized by the so-called second escape velocity, equal to V p ≈ 11,200 m/s, which allows you to overcome gravity. Movement along a parabola relative to the Earth is possible only in the absence of other forces of influence other than the force of gravity.

Hyperbolic orbits are characterized by velocities V g > 11,200 m/s, which includes the third escape velocity ( V g ≈ 16,700 m/s) is the lowest initial speed at which the spacecraft can overcome not only earthly, but also solar gravity and leave the solar system.

It should be taken into account that due to the rotation of the Earth, the launch vehicle with the spacecraft acquires a certain initial speed, which, when launched in the eastern direction, is: at the equator - 465 m/s, and at the latitude of the Russian Plesetsk cosmodrome - 210 m/s.

In practice they are implemented various methods launching a spacecraft into orbit, each of which affects many parameters, such as the required energy, the thrust change program, the parameters of the launch vehicle stages, the duration of the launch, the visibility conditions of the launch sites from certain points, and others. However, the main requirement determining the choice of the type of extraction remains the requirement to minimize energy. There are three main types of output:

− fully active output (direct output);

− ballistic output;

− elliptical output (with or without a section of motion along a perigee circular orbit of radius equal to the perigee distance of the transfer orbit).

During direct insertion, there is only one active section, the motion parameters at the end of which must coincide with the required orbital parameters of the spacecraft motion. This type of output, compared to the two subsequent types of output, is less economical because with increasing duration of the active section, energy consumption to overcome increases. gravitational forces. Using this method, it is advisable to launch spacecraft only into low (up to 400 km) orbits. In this case, the issues of choosing the optimal launch vehicle motion program that ensures a minimum of energy consumption become important.

During ballistic inference, trajectories similar to those of ICBMs are realized, which are arcs of elliptical trajectories in the central gravitational field. In this case, the top of the elliptical trajectory must touch the orbit into which the spacecraft is launched. At the top of the spacecraft trajectory, an additional impulse is imparted to the required orbital speed (second active section). This method, compared to others, has the following properties: shorter flight time, direct visibility during insertion, more favorable conditions for rescuing individual stages of the launch vehicle. The limit of altitudes for which the ballistic type of output is more acceptable from the point of view of energy consumption is about 1,000 km.

With an elliptical launch, the spacecraft is first launched into a low-altitude circular orbit (180...200 km), in which (immediately or after some time) it accelerates to the perigee speed of the transition ellipse (Hohmann trajectory), at the apogee of which, touching the given orbit, the spacecraft accelerates to required orbital speed.

Wide Application in astronautics, it is found in the geostationary orbit (GSO), located in the equatorial plane with an altitude above the earth's surface of 35,809 km. The inclination and eccentricity of this orbit are zero, the movement occurs in an easterly direction with a period equal to the daily rotation of the Earth (23 hours 56 minutes 4 seconds).

The most beneficial from an energy point of view is launching a spacecraft into geostationary orbit from launch pads located at the equator. Launching a spacecraft into geostationary orbit from Russian cosmodromes is more complex, since it requires an additional change in the plane of the spacecraft's orbit. This energy-intensive maneuver is carried out, as a rule, with the help of special repeatedly switched on stages of the launch vehicle - upper stages (UR). In this case, injection methods are used, including passive sections and reference orbits. At present, two- and three-pulse launch schemes have found practical application for launching spacecraft into geostationary orbit, as well as using the lunar gravitational field to rotate the orbital plane. Upper stages are also used to launch spacecraft onto interplanetary trajectories.

When launching a satellite into orbit, the launch vehicle usually imparts its initial speed after crossing the dense layers of the atmosphere, at an altitude of at least 140 km. At the moment when the required orbital speed is reached, the engine of the last stage of the launch vehicle is turned off. Further, one or more may be separated from this stage artificial satellites, intended for different purposes. At the moment of separation, the satellite gains a small additional speed. Therefore, the initial orbits of the satellite and the last stage of the launch vehicle are always somewhat different from each other.

In addition to one or several satellites with one or another equipment and the last stage of the launch vehicle, some parts are usually launched into close orbits, for example, parts of the nose cone that protects the satellite when passing through dense layers of the atmosphere, etc.

In principle, the starting point of the satellite’s motion can be any point in its orbit, but the characteristic velocity of the launch vehicle will be minimal if the active segment ends near perigee. In the case when the perigee is located near dense layers of the atmosphere, it is especially important that the speed acquired by the satellite during acceleration is not less than a given value and that its direction minimally deviates from the horizontal (Fig. 3.15, a, b). IN otherwise the satellite will enter the dense layers of the atmosphere without completing even one revolution.

If the planned orbit is located high enough, then small errors do not threaten the destruction of the satellite, but because of them, the resulting orbit, even if it does not cross the dense layers of the atmosphere, may be unsuitable for the intended scientific purposes. The orbital insertion portion typically includes one or more passive intervals. At a high perigee of the orbit into which the satellite is being launched, the passive phase of the launch can be more than 10,000 km in length. The launch trajectory, which is, generally speaking, a spatial

curve, located near the plane of the satellite’s orbit. If the launch is made exactly in the easterly direction, then the inclination of the orbital plane is equal to the latitude of the launch site. In this case, the orbital plane touches the parallel. In all other cases, the orbital inclination can only be greater than the latitude of the cosmodrome (in particular, when launching at westward, when the orbital plane also touches the parallel of the cosmodrome, the inclination should be greater than 90°). The orbital inclination can be less than the latitude of the launch site only if a maneuver is provided to change the orbital plane after the launch.

Methods for launching a satellite into orbit are shown in Fig. 3.16.

In the active phase, a satellite may separate from the launch vehicle even before the last stage is turned off. After switching off, the second satellite may separate. Obviously, the orbits of the two satellites will be different, but their perigee altitudes will differ little, since during the additional acceleration the last stage could not rise too high. Apogees can be at different heights, because even a small increase in the initial speed sharply raises the apogee.

The separation of two satellites during the active phase of the last stage flight was first carried out on January 30, 1964. At the same time, the Soviet satellite Elektron-1 was launched into orbit with a perigee altitude of 406 km and an apogee altitude of 7,145 km, and the Elektron-2 satellite - with altitudes of 457 km and 68,000 km, respectively. The choice of orbits was determined by the goals of the launch - the study of the inner and outer parts of the radiation belt.

In cases where the intended orbit of the satellite is circular at high altitude, or elliptical with a high perigee, or elliptical with a low perigee but with an apogee located in a certain region of space, it may be necessary to pre-inject the satellite into a low intermediate orbit. This requires additional impulses supplied by the upper stage of the rocket or the onboard engine of the satellite.

Let us assume that having a cosmodrome at point A (Fig. 3.17), we want to place the satellite into an elliptical orbit with an apogee located above point A. Having accelerated the satellite to a circular speed at point B, we will place it into a low intermediate orbit 1. If we now report satellite at point C increases in speed by turning on the engine of a new stage or re-turning on the previous stage, the satellite will move to an elliptical orbit with an apogee located above A. A similar technique is used when launching Soviet communications satellites of the Molniya type, the apogee of which should be located at an altitude approximately 40,000 km certainly over the northern hemisphere (but, of course, not necessarily over the cosmodrome). The difficulty of such a launch is that point C is outside the radio visibility zone of tracking radar stations.

If at the apogee of the elliptical orbit one more speed increment is given, then the satellite can be transferred to a new orbit. In particular, if we bring the speed at point D to the local circular one, then the satellite will move to circular orbit 3. If point D is at an altitude of 35,800 km, then we will get a daily satellite with an orbital speed of 3.08 km/sec, and if in addition the cosmodrome and and the orbit is in the equatorial plane, then stationary. If point A is not on the equator, then at the moment of crossing the equatorial plane, it will be necessary to correct the position of the orbital plane with another impulse. The position of point C in intermediate orbit 1 is selected so that the stationary satellite is located above a given point of the equator. Usually, due to errors in the satellite's orbital period, this is not immediately possible. The satellite begins to slowly “drift” to the east or west, and additional orbital corrections are necessary to stop it above a given point, and subsequently to compensate for the inevitable disturbances. Finally, at the apogee of intermediate orbit 2 (not necessarily at an altitude of 35,800 km), the local circular speed can be exceeded using an onboard engine, and then point D will become the perigee of a new elliptical orbit 4. In this way, satellites are launched into elliptical orbits with high perigees. An example is the American communications satellite Relay-2, launched on January 21, 1964 into an orbit with a perigee at an altitude of 2,091 km and an apogee at an altitude of 7,411 km.

It is curious that, using two intermediate orbits 1 and 2 (Fig. 3.17), it is possible, using one launch vehicle, to launch two satellites into the same circular orbit (or almost the same) so that they are simultaneously in two significantly different points of this orbit. To do this, it is enough, after launching one satellite into orbit 3 at point D, to allow the second satellite to complete an entire revolution along orbit 2, so that when it reaches apogee D again, it will finally be launched into orbit 3. You can select the revolution periods of orbits 2 and 3 so that both satellites ended up at a given distance from each other along the orbital arc (in principle, even at the ends of the same diameter). In this way in the USA in 1963, 1964, 1965 and 1967. Four pairs of Vela-Hotel inspection satellites (to detect nuclear explosions in space) were launched into circular orbits at an altitude of approximately 100,000 km, with one satellite in the pair being 130 - 140° ahead of the other. During all launches, a third, scientific satellite, remained in intermediate orbit 2.

The process of launching an artificial satellite into a stationary orbit (Fig. 3.18) can be represented step by step as follows (Fig. 3.18, a):

– launch from a launch position located near the equator, in an eastern direction to a holding orbit at an altitude of 185...250 km;

– at the moment of crossing the equatorial plane, the satellite is transferred from the waiting orbit to an intermediate orbit, the apogee of which coincides with the altitude of the synchronous orbit;

– carrying out the necessary orientation maneuvers in the intermediate orbit to prepare for turning on the apogee engine;

– after completing several orbits along the transfer orbit, transition using the apogee engine to an orbit close to circular;

– precise translation of the satellite to a point above a given longitude and correction of its orbital period and orbital eccentricity; transfer of the satellite (if required) from the rotation stabilization mode to the three-axis stabilization mode and deployment solar panels;

– periodic correction of orbital parameters to ensure that the satellite is located above a given point on the earth’s surface.

It is possible to launch satellites into orbit according to the scheme presented in Fig. 3.18, b.

Ptuf 53 · 10-09-2014

The union is certainly good. but the cost of removing 1 kg of cargo is still prohibitive. Previously, we discussed methods of delivering people into orbit, but I would like to discuss alternative methods of delivering cargo to rockets (agree to throw a person and a piece of iron (satellite) is still a big difference). I think projects that are not real at all (such as a tower or a space elevator) should not be touched. but the EM gun can be discussed. Who has any thoughts? (Maybe someone has read a recent article)

Dilettant 111 · 10-09-2014

I remember about 30 years ago there was a film about a “space” gun, I don’t remember the details, but the height of the shot was very high.
I don’t know for what reasons the Americans abandoned the project, but in my opinion it is a quite suitable method for launching small satellites.
The truth about the cost is that the commercial component is unpredictable, as in the joke about brokers:
Twice two, how much is it?
Are we selling or buying?

An electromagnetic (aka magnetofugal - in a word!) gun is a gadget quite suitable for launching cargo into Earth orbit. The truth is so far exclusively in the form of metal blanks, because no electronic filling can withstand SUCH overloads.
There was a rumor on Internet forums that some guy calculated what the length of the gun should be in order to accelerate the projectile to the first escape velocity with acceptable acceleration. I don’t know the details (and in general, maybe they’re all lying), but it seems like he got a gun with a barrel length of somewhere around 1000 km.

Back in 1935, Max Valier came up with the idea that it would be possible to first accelerate a projectile in a ring tunnel, then “switch the switch” and direct it into the “barrel” tangentially adjacent to the ring accelerator, thus launching it in the desired direction. direction. This kind of nuclear accelerator is overgrown for “collective farm” needs.
For better effect, it was proposed to spin the projectile in a vacuum.
It was absolutely impossible at that time to assemble a “arrow” capable of switching at such a speed (now, however, it is also still impossible).
Plus, the shock during the transition from vacuum to atmosphere during the shot will be enough to turn the satellite into a well-done pancake - what did he want at the first cosmic speed, but not into the thin upper layers, but into the plump lower ones!
After such problems, overcoming the destructive effects of centrifugal force in a military accelerator is an easy workout for the mind.

Theoretically, the EM device could be used to launch satellites from the Moon: the first spacecraft there is much smaller, and there is no air. But this is, of course, if before this we solve the difficulties with a compact and powerful energy source, a heat sink and how to deliver it all there and mount it there. But maybe in the future...

Oh yes. Another problem is the size of the satellite. You can’t fire people from such a gun; you’ll have to overcome too many engineering hemorrhoids. But shooting cubesats into orbit, at least in theory, is quite possible. But even for this, a bunch of related problems will have to be solved, such as the fragility of the electronics, the energy source, changing the direction of the shot, etc.

In short, for all its beauty, the idea of a magnetic fugitive launcher is still unpromising due to the high costs of solving technical problems and the small useful “exhaust”.

In the meantime, only warriors look at “railguns” with cautious optimism - after all, throwing a blank into the side of an enemy ship or tank, or anything at all, at a distance of 200 km at a speed of about 6 km/sec is, let me tell you, always a pleasure.
But even among the “star-driven” there are skeptics. The thing is that EM guns are extremely bulky, so they can only be placed on a large tank or ship, and are wildly vulnerable: any hit by a shrapnel into the power plant (and it is “present” separately from the gun itself and is also never small ) - and the fireworks on May 9 will seem like just a dull sparkler! And the weapon itself is not distinguished by increased survivability.
Well, there is also quite a lot of wear on the rails after each shot (in the case of a railgun), which affects durability and accuracy; plus the problem of heat removal, and fast one at that - apply several million amperes to the same rails within a fraction of a second - anything will overheat. And if in the case of launching satellites this does not play a role - you shoot once, then let it cool for a month - then in battle, after several shots, the gun can stupidly melt!

Nope. It turned out a little chaotic. Still, compilation from different sources, which touch on the space sphere only in passing, and even with “sawing up” of the original source (thank you very much to fellow legislators and moderators) does not contribute to improving the quality of the commentary. But what are they rich in...

There is also, proposed by Rogozin, a trampoline and a super slingshot, as in the joke.
The only real thing left is the chemical rocket. And we can talk about a reduction in price only within 10-20%, this is realistic, but it seems that this is the limit, I take into account the total cost of the cycle, and not individual stages.
True, the price can be reduced within these limits by changing just one condition; it is necessary to exclude the possibility of theft at all stages, starting with design.

Lipa 23 · 12-09-2014

Well done Dim - detailed and clear! EM gun to the dustbin of history! This is an unacceptable option for space (I also read about it), but the warriors really became interested in railstones and learned to shoot hot plasma from them (the charge melts and flies at high speed) well, you need to break through the energy, there is no rate of fire (yet), but if you hit it once there is no need to repeat. The soldiers are happy, but what should we do? So how about flying on kerosene gas? So we’ll be hanging around in orbit like poop in a hole. A rocket is not an option - you need to sculpt something reusable (not like Musk’s grasshopper and rocket “with flippers”), but truly reusable.

DimitriyP 113 · 12-09-2014

Theoretically, there is an option to reduce the cost of launching a rocket (at least in theory) as a result of placing the energy source outside of the rocket and transferring this energy “through the air” directly on board, for example, with a laser beam or something like that (although the laser will not penetrate here, but it will do to illustrate the principle). The idea is not new, but this still does not bring it closer to a solution.
However, a lot will depend on the cost of such “teleportation”, otherwise it may end up being even more expensive.

DimitriyP 113 · 12-09-2014

Wow, while I was writing the above post, lipa had already posted three (at least) and was severely banned! And I didn’t even have time to read... However, it’s sad!

Dilettant 111 · 12-09-2014

“Somehow the evening is no longer languid.”
Moderators ban in a black way, after a day someone has to be saved, and what is especially disgusting is that they leave a red mark, better without a trace or the point of violation for clarity.
Damn, I'm tired of it, I didn't have time to read it and the thread of the discussion is lost.

DimitriyP 113 · 12-09-2014

dilettant. I support!
Comrade moderators, if you would at least write under a ban for what reason, you’ll see that people would stop “sprinkling sedition.” Otherwise, the moral and ethical principles that you follow when moderating your next post are very often not clear.
And so the people see the borders, and you have less work.

Delitant 76 · 13-09-2014

“a gun with a barrel length of about 1000 km.” It’s easier to install an elevator in the barrel and make cutouts at different heights, and even cheaper - a hanging ladder. But this is provided that the barrel is pointed towards the sky.

Dilettant 111 · 13-09-2014

It was proposed to use the mountain to build an acceleration tunnel, but it would be expensive at the very beginning, and the range of launch into orbit is too small.
You can only compare the costs of the entire launch program, with this approach it will be clearer which method is cheaper, otherwise they stick out the figure of payment for “Russian” delivery, forgetting that Russia contains cosmodromes and rocket production facilities and a network of escort stations. Such clever people come and say that we have a satellite and we need to launch it into orbit, but we want the launch to cost the same as rocket fuel. Would you like some horseradish with butter? Take on some of the complex costs and the launch itself will magically become cheaper. If you order a full range of services from a transport company, you get one price, but if you only deliver cargo from point A to point B, then the price will be much lower.
While earthlings have only flying kerosene stoves, everything else is exotic and fantastic.
Just the other day they showed a story about a 3-D car, the printer takes a week to print the body, the number of parts is orders of magnitude less, the wheels, the engine, and everything else is done in the usual way, the assembly is manual, the body must be processed with a file, the cost of such an electric car is 20-30 thousand in foreign countries currency, the same serial “regular” one will cost 3-4 thousand at most. There seems to be progress, but the cost is still going through the roof.
You can say that space is a whim, that you can build a wonderful life for yourself without aiming at space exploration, all this is also a point of view that deserves respect, but I will say this, personally, I can be patient a little and do without a consumer society, that is, live sensibly -enough, and the money raised from this should be used for some progressive developments, not necessarily space, but at the same time have control over the expenditure of funds.
For those who will try to use this fund only for the purpose of enriching themselves, one single punishment will be imposed: deportation to airless space with confiscation.

Ptuf 53 · 15-09-2014

I wanted to write on Friday but didn’t have time. In those three posts there were 3 articles, one very detailed one, starting from the dawn of astronautics, substantiating the economic benefits of using the Russian MAKS system, buried in the dashing 90s. The article is long and interesting; writing “in your own words” is too lazy and complicated. Therefore, I dumped it as is in the hope that it wouldn’t be deleted quickly and people would have time to read it. The second was from the youth technology magazine for the 11th year about the use of a cable propulsion device. Well, there are also “alternative” ways. The supply of offers on the Internet is through the roof. There are some interesting ones and some crazy ones. but there are a great many of them and to claim that there are alternatives to chemicals. there are no missiles somewhat frivolously. While reading, I realized several things: all projects using guns and their analogues (and there is also a method of launching by accelerating an object in a spiral and others) are not feasible for several reasons
1) Firstly, the drag of the lower layers of the atmosphere at hypersonic speeds will be very high (even compared to a concrete wall). and will destroy almost any object if it is not provided with powerful thermal protection (which complicates the process and makes it significantly heavier)
2) Secondly, any launched body will return after one revolution to the launch point, regardless of the speed. that is, it will be necessary to adjust the orbit, that is, to equip the object with a propulsion system. Which also greatly affects the cost and complexity and, taking into account the first fact, is also technically problematic due to large overloads (the electronics will be messed up, however, and without it the engine will not turn on in time).
3) The initial speed must be significantly higher than the 1st cosmic speed due to braking in dense layers of the atmosphere (quite strong) and this is not all the problems.
From the data studied, it became obvious that the main problem for rockets is precisely overcoming these densest lower layers of the atmosphere (the first 11-12 km of altitude). Acceleration and achievement of launch into orbit are carried out by the 2nd and 3rd stages of the rocket, and the first is precisely used for ascent to these 12 km And eat the lion's share of fuel - according to calculations, the flight of the 1st stage of Proton lasts 65 seconds. and during this time, either 250 or 280 tons of fuel burns (the exact figure was in the article, I don’t remember). And air launch saves a lot of money. In the calculations there was a figure for "MAX"; the cost of transporting 1 kg of cargo was supposed to be 1000 and in the future 500 bucks (which, you must agree, is no longer mullions as it is now). This truth has been known for a long time (somewhere since the mid-60s) and many have tried this solve the problem. The path of Musk with his grasshoppers is a dead end in my opinion. but our “Baikal” and “MAX” seem to be promising (but became victims of bureaucracy and the collapse of the USSR). There are others like this. And the problem of solving these first 11 km will significantly reduce the cost of removing cargo. An elevator, a tower and similar megalethic structures are technologically not feasible at the moment, and also politically (it must be built together and on the equator - the Negroes who live there do not need this, and the USA and Russia will not be allowed into Africa. There is a lot more that can be written, but the time is already lacks.

Yes, here’s the thin Earth’s atmosphere for you.... In general, the solution to the “first-stage problem” (as well as the very issue of reducing the cost of launch in general) very much depends on what and how much weight is proposed to be launched into space.

I think so, no matter how much we hope, no matter how much we deceive ourselves, but in the next 100 years we will be flying on kerosene gas. Maybe later, when some new physical principles are discovered and a “flying saucer on anti-gravity” is built, this will immediately reduce the cost of delivering cargo a hundred million times, but for now... Yes, here’s the thin Earth’s atmosphere for you.... But in general, a solution " problems of the first stage" (as well as the very issue of reducing the cost of launch in general) very much depends on what and how much weight is proposed to be launched into space.
Thus, it will not be difficult to make it cheaper to launch small and light “cubesats” into orbit. Due to their weight and size, even a relatively small rocket can throw them into space, which can easily be “attached to the back” of a high-altitude aircraft or hooked onto the same stratospheric balloon.
And here Mask and his comrades are surrounded by complete freedom and prosperity. Here you have “grasshoppers” and magnetic fusers and in general a bunch of all sorts of alternatives.

It’s another matter if you need to bring out something really worthwhile: a telescope there, 2-3 cosmonauts (or 6-7 taikunauts:)), or a module of some station. Then you will need a larger and thicker rocket, and it will no longer fit on the plane, and the “grasshoppers” will no longer save it.
And this is where you have to tinker with the rocket itself, the engines and the fuel. What is the main criterion here? Weight! Therefore, by making the rocket lighter, we can make the launch cheaper.
After all, now it’s like - along with the payload, a huge amount of “unnecessary” iron and heavy fuel is flying into space. It is in this direction, it seems to me, that we need to work: to reduce the weight of the rocket and satellite itself through new materials and engineering solutions, plus to develop new energy-efficient types of fuel so that a small amount of it burns “long and brightly.”

I think so, no matter how much we hope, no matter how much we deceive ourselves, in the next 100 years we will be flying on “kerogas”. Maybe later, when some new physical principles are discovered and a “flying saucer on anti-gravity” is built, this will immediately reduce the cost of delivering cargo a hundred million times, but for now...

DimitriyP 113 · 15-09-2014

What a bummer, the text was copied twice! And everything looked decent...

Okay, they say repetition is the mother of learning; I don’t know if there’s a lot of “science” in my post, but those who didn’t understand the first time will have another chance!

DimitriyP 113 · 16-09-2014

ptuf. I foresaw this outcome and copied it to my computer (I hope someone else thought of this before or managed to master it). True, I haven’t had time to read it yet, but as soon as I can, right away.
In any case, thanks for the info.

Ptuf 53 · 17-09-2014

YOV2 38 · 23-09-2014

Well, what can I say to shoot blanks (a set of bolts, rolled sheathing, disassembled frame elements) with a standard gun! and all the thin little things, in the old fashioned way, join them into a train and off to Mars!

YOV2 38 · 23-09-2014

and digging a hole in the ground or in the mountain is not at all necessary
but the mountain will come in handy! There is a mountain with a suitable slope, well, you can clean it up right away and build that tunnel right along the slope; there are mountains more than a kilometer away, so a tunnel can be built!

Sqwair777 50 · 23-09-2014

YOV2, “Well, what can I say: shoot blanks (a set of bolts, rolled sheathing, disassembled frame elements) with a standard cannon! And join all the thin little things in the old fashioned way into a locomotive and to Mars!”
And then how to catch it? At such and such speeds. Then you need to come up with a mechanism for braking and stabilization, in one place. Instead of racing with a net around orbit, God knows at what speeds. And there is also a possibility of shooting into some satellite.

Dimitpij 46 · 24-09-2014

Yakov, should you read what is written above about the use of guns? The details are detailed there:
1) A projectile launched along a ballistic trajectory will plop down at the launch point after one orbit - without any correction.
2) In the lower layers of the atmosphere at hypersonic speeds, the blank will heat up to red hot (it doesn’t matter to the projectile - the load is bad) That is, thermal protection is needed.
3) Due to braking in the lower layers of the atmosphere, the speed should be much higher than 1st cosmic speed, and these are prohibitive loads and resistance (at a speed of 10 km / s, the lower layers of the atmosphere = a concrete wall).
The result is that various versions of guns are only suitable for the military (to jam the Paris and knock down satellites). The idea is stillborn!

YOV2 38 · 25-09-2014

Note that the idea is not mine at all (see above)
I just wanted to say that technically such a device is far from being so prohibitively complex.
but with practical application Well, the problems are really more complicated than with construction.

YOV2 38 · 25-09-2014

here is simple garbage with a shot from a cannon, initial speed max. and then falls and air resistance decreases with height, i.e. the decrease in speed due to resistance decreases and here the current in the question of calculations is what will remain from the initial impulse.
but I would like exactly the opposite to smoothly accelerate, which is what rocket systems do.

YOV2 38 · 25-09-2014

it would be easier to exclude air from the equation + some kind of initial speed - which is what they are trying to implement when launching from “flying missile carriers”
Well, there are completely futuristic projects, the implementation of which is possible or not possible, but obviously for now it will be more expensive

And here on the AstroForum the namesake posted news a couple of days ago that scientists seem to have gotten their head around making especially strong threads, like diamond ones. And it seems like learn how to grow them in industrial scale- the space elevator is provided. And somewhere else I’ve already heard about developments in this area.
In short, if things continue like this, it may well happen that we will soon be riding an elevator into space!
Hmmm... I wonder if the Space Elevator profession is a heroic profession, or just an ordinary one?

Sqwair777 50 · 25-09-2014

DimitriyP, cosmolift - utopia. No material of this length can even support its own weight. And besides, what will the cable hold? And simply, even if something holds it in a static position, it will simply be wound around the Earth, but as for strength, see above.

DimitriyP 113 · 25-09-2014

Sqwair777. Truly a utopia! In general, all sorts of different “scientists” and “inventors” come up with all sorts of stupid things!

Here, they say, somewhere in the North American States lived two brothers. So they decided to make some kind of miracle with wings and a motor so that they could fly with THIS! Well, isn't it nonsense?
Everyone knows that flying on any heavier-than-air craft will be incredibly energy-intensive and therefore ineffective. Even if you manage to get into the air with the help of such a device (which is unlikely), then you certainly won’t be able to stay there for long enough!

Or I also remember there was one “eccentric”. So he argued that over time a person will overcome Earth's gravity and will be able to fly into space. On a rocket!
Well, how narrow-minded do you have to be, um... to assume such a thing! Not only will it take so much fuel to overcome Earth’s gravity that the rocket simply won’t be able to take off from the ground, but even if we assume that by some miracle this still happens, not a single material in the world can withstand SUCH pressure and temperature in the combustion chamber. It will just melt and explode!
Supporters of this idea can only be advised to douse themselves with kerosene, set themselves on fire and throw themselves into the abyss - the death will be similar, but how many resources will be saved in the end!

In short, I agree - the space elevator is technological nonsense and a chimera, and man will never build it!

YOV2 38 · 26-09-2014

Well, there's a tricky thing with numbers
It seems that the transfer of the cargo itself will be completely for nothing, but just for the sake of this one cable it will be necessary to create an infrastructure and even an entire branch of production, and putting such cables into production seems to be also pointless and where to put this new industry. and that's the price per circle!?

YOV2 38 · 26-09-2014

and with ideal placement you need to hook it on the equator! and there it’s normal, it’s AFRICA and there everything’s not normal at all, there’s an epidemic of revolution, it’s going to have to raise some kind of CONGO!

Dilettant 111 · 27-09-2014

Diamond nanotubes are beautiful, but actually they are carbon, and the problem is that so far they can only make them three centimeters long, but they need many kilometers, and even weave them into a rope.
But if we take into account the progress in the ability to produce nanotubes, cables of the required length should appear just by 2050, purely theoretically.

Flibustier51 58 · 24-03-2015

The topic somehow died out, I’ll add what I found:
An An 225 cargo plane.
“The third purpose of the Mriya - to become a flying cosmodrome - has so far remained a dream. Although the deputy general designer of the Antonov ASTC, Oleg Bogdanov, assured us: work on the mobile space launch project is underway in Russia, albeit very slowly, because there is no money for it . But this idea is not outdated, because it was ahead of its time by at least half a century. It is simple and elegant: an external fuel tank is installed on the “back” of the An-225 with an orbital aircraft attached to it in a manned or unmanned version. This mini-Buran is the size of "smaller than the large Buran - its length is only 19 m versus 26.
At an altitude of 9-10 km, the launch takes place: "Mriya" makes a "slide", at the moment of descent, a "space passenger" is separated from it, the engines are turned on, and the ship goes on the desired course, and "Mriya" returns to the airfield. After completing the task, the "shuttle" also lands on its own, and it does not need a special runway (runway), an ordinary 1st class airfield (with a runway only 5 km long) is sufficient. Such a space plane is designed for 100 launches. A crew of two can deliver to orbital station cargo weighing up to 8 tons, launch a satellite into low orbit (up to 400 km).
But the value of the project is not only that putting a kilo of payload into orbit using a mini-Buran costs three times less compared to disposable Soyuz launch vehicles ($12,000-15,000/kg) and reusable launch vehicles for the first generations - "Buran" (USSR) and "Space Shuttle" (USA) - (up to $22,000/kg). The main thing is the ability to launch in any direction, efficiency. This means that such a ship can be a lifeboat for a spaceship in distress, no matter where it is.
Alas, turning all this into metal is not only expensive (about $10 billion), but also difficult due to the fact that after the collapse of the USSR, Mriya began to belong to Ukraine, and all space projects are concentrated in Russia. So far, Russians are not interested in a mobile start. There is no money, and they don’t really need MAX - they use old, time-tested, disposable Soyuz to deliver cargo to the ISS orbital station, regardless of current costs."
It turns out that everything has already been invented.
The An 225 was built almost 30 years ago, I think that now they can make an even larger aircraft that can lift a larger shuttle with cargo, if necessary. And he has an advantage: he can deliver the shuttle anywhere and launch where necessary.

Flibustier51 58 · 27-03-2015

The next thread addresses the problem with space debris. Every year it becomes more and more.
You can launch somewhere from an equatorial island, having built there only a runway for a cargo plane, an aircraft refueling station and a mini. necessary. The amount of debris from such launches can be minimized by programming the shuttle's upper stage to fall into the ocean (as when launching from Florida, there is water all around). You can also use it again (same as when launching the Shuttle).
And then the shuttle will land at the “home port” of its country, then it will pass there. They are designed for 100 launches.
Pros:
1) launch is 3 times cheaper than the current minimum (from the equator it will be even cheaper), additional costs for a flight to the equator are relatively small, for example, a transatlantic flight of Mriya costs about $100 thousand. The shuttle and jet fuel can be carried on ships, for that matter.
2) The problem with subsequent debris in orbit has been solved, there is less harm to the environment (the launch area is sparsely populated and less rocket fuel is used).
If you seriously develop space and build spacecraft. base or ship in orbit, then this option provides a clear advantage.

Dilettant 111 · 03/27/2015

Yes, you can completely abandon vertical launches with this concept, but the weight of a one-time payload will be significantly less than what the rocket can launch. Mriya, of course, is an aircraft with outstanding payload capacity, but its speed is not enough. The accelerator must gain at least 4-5 Mach speed, Mriya will never accelerate before that. The requirements for the airframe are too different, the super-heavy configurations do not allow the development of the required speeds, and the hypersonic aircraft does not have the required payload capacity. This antagonism must be somehow eliminated for the project to work to its full potential.

Dilettant 111 · 28-03-2015

I don’t want to argue with the ideologists of the project, but my technical experience does not allow me to take on faith everything that is beautifully shown on the internet.
The moment of separation of the load, that same slide, or rather its (slide’s) top point, the carrier aircraft goes to the horizon at the highest point of the parabola (separation of the payload occurs in horizontal flight at the moment when the “womb” goes into a peak, the beginning of a state of weightlessness) the shuttle must begin accelerating from subsonic speed while simultaneously gaining altitude. And you need to accelerate to the first space speed, and this, by the way, is not 1 km/sec, but much more, more than seven times, there will be practically no gain, but, in my humble opinion, there will even be a loss. If you don’t believe me, then watch the video on YouTube of how spacecraft are launched into orbit, where there is telemetry. In order to accelerate the spacecraft to the required orbital speed, the last stage of the rocket operates with a decrease in altitude in order to obtain a gain in payload weight, this may seem paradoxical, but this is ballistics!

Article from 2013: “The Advanced Research Foundation (APF), established earlier this year under the government, plans to implement the “Air Launch” project in the 2020s - launching an orbital aircraft (spaceplane) from a super-heavy transport aircraft, says the report of the Public Council under the Military -industrial commission under the government of the Russian Federation, distributed during a council meeting in the State Duma...
“The first step on the path to commercial space exploration could be a multi-purpose aerospace system - a two-stage space complex project, quite developed back in the 80-90s, which consists of a carrier aircraft (An-225 Mriya) and a launch vehicle an orbital spacecraft - a rocket plane (cosmoplane), called an orbital plane," says one of the paragraphs in the section on priority areas of research and development of the Fund."
In the long term, the authors of the report propose using a “space elevator” to deliver cargo into orbit, which could appear within 60-70 years.
The authors of the report note that space shuttles such as the Soviet Buran and the American Space Shuttle turned out to be excessive in capabilities and too expensive to operate. “Nevertheless, the very idea of a “space plane” - a reusable shuttle capable of performing both military, scientific and commercial tasks, continues to remain relevant. In the future, this technology, if implemented correctly, will dramatically reduce the cost of transporting cargo into orbit and will open the way to further commercial and military use of space," is noted in the priority areas of research and development of the Fund..... ""
Experts say that this method of delivery will “drastically reduce the cost”, so is it still profitable? And the cargo plane is precisely "Mriya", i.e. subsonic speed.
“The first cosmic velocity is the minimum speed at which a body moving horizontally above the surface of the planet will not fall on it, but will move in a circular orbit.” Horizontally, and the shuttle will fly vertically, it does not need to reach the PCS, it is enough to overcome the acceleration of gravity (g). At an altitude of 10 km it is less, and so is the air resistance.

Flibustier51 58 · 29-03-2015

More on this topic: “In the United States, the largest Roc aircraft in the history of world aviation is being built in the Californian Mojave Aerospace Port, which is planned to be used to launch spacecraft from the stratosphere.
The wingspan of this machine is 117 meters, the total maximum weight is 540,000 kg. The Roc's dimensions are larger than all other aircraft, such as the Boeing 747-8, Airbus A-380-800, or Hughes H-4 Hercules.
The project is being developed by billionaire Paul Gardner Allen, co-founder of Microsoft and investor in numerous amazing startups and projects, including the SETI Institute's Allen Telescope Array and SpaceShipOne, the first private suborbital flight.
If everything goes as the developers planned, then the first test flight of the new machine could take place as early as 2015, and the first launch of a rocket from its board - in 2016."

The main difficulty is to catch the cargo in orbit. There should be something like a target barge to shoot at. It is the barge that makes the adjustment to the maneuver; it will have about 7 minutes of time while the projectile is flying. The speeds will be approximately the same, so catching the projectile will not be too difficult, provided that all calculations are made correctly.
Transferring energy with a laser is also an interesting option. But it is not entirely clear what principle of movement the rocket itself will use after receiving energy. Reactive turns out not suitable...
WITH space elevators- too utopian an idea. People will build orbital ports faster than they will produce material for cables.
But in general, the idea with orbital ports is very interesting, but very ambitious in its concept. In this case, you need a specific place for construction as well as material. Arctic or Antarctica. Well, a good half of humanity should participate in construction. This is an ambitious project... Maybe it will stand when resource extraction on asteroids and satellites begins to actively develop.

All about car tuning

Launching spacecraft into orbit. Soviet orbital trick. Orbits of artificial earth satellites

Types of orbits

Aerodynamic paradox

Orbit characteristics

High near-Earth

Low near-Earth

Sun-synchronous orbit

Injection into orbit: launch

Adjustment

Space debris