You are here. ⇡ Will we wake up tomorrow in a new world? ⇡ Planned landing

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That's when their Falcon 1 flies, then we'll talk.

That's when there will be a contract with NASA, then we'll talk.

That's when they build their ship, then we'll talk.

That's when they figure out how to land rockets, then we'll talk.

That's when they put on a barge, then we'll talk.

You are here.

But "here", of course, does not mean anything. Let's briefly describe this place.

You are on the street of the 30th Irkutsk division, building 8, apartment 219.

There is a Magnolia store in your house, the day before yesterday they brought supposedly Moroccan tangerines, but they don’t even taste Abkhazian. You even thought for a minute where such sour meat could be grown, but you have no versions.

The upstairs neighbor is constantly drilling something, the downstairs neighbor is banging on the battery. At first, you thought that your TV was too loud when you watched TV shows, but then a neighbor woke you up by tapping on the radiator at three in the morning, and somehow felt better.

There is a serious discussion on TV about whether a priest should be held responsible for a failed rocket launch. Before that, they also seriously discussed what films can be made about the king, but you don’t remember what conclusion they came to. Judging by the fact that the mausoleum and Voykovskaya station are still with us, probably any.

You are here, where money for the treatment of seriously ill patients must be collected by the whole world, and then these patients should be treated in another country, because here, on the street of the 30th Irkutsk Division, money does not guarantee anything.

Where presidential elections are so meaningless that candidates talk about it openly.

Where your pension savings have been frozen for several years (and you don’t understand what it is, but you feel that a good thing will not be called a freeze), and 8.5 billion rubles were found in the colonel’s apartment.

You also found money yesterday, two hundred rubles in the pocket of your winter jacket. At first they were very happy, and then they read about the colonel.

You are here where the city to travel must go. And an amazing thing - after the roadway was narrowed in the center, there were more traffic jams, who would have thought.

Where dumplings cost six hundred rubles, after all. Yes, in fact, this price also does not guarantee anything, except, of course, that after buying dumplings you will have six hundred rubles less.

Well, that is, taking into account the fact that you found two hundred, then after buying dumplings you will have minus four hundred rubles. Here this arithmetic does not seem strange, here the laws of history, mathematics and physics behave differently.

Here, which you got, seems to be a little expired, and everything is possible in it, especially if it all somehow crap you.

In the morning you look at yourself in the mirror and see above you the fiery letters "not subject to warranty repairs."

Surely, of course, there is something good here. But you are here anyway. Not in this list above, but here. You entered the list like that, to visit, to dream.

As for the good, you have to add it yourself. Therefore, in the evening you brew strong coffee, watch TV shows on headphones for a long time, eating them with dumplings in barbecue sauce - even so, they do not look very much like dumplings.

At 2.45 you get up from your chair. Everything was mixed up in my head from lack of sleep and serials, Flash again saved the planet and had dinner with pseudo-dumplings.

You pick up a hammer and approach the battery. At first you knock rarely, waiting for the echo to die down, then more and more often. The neighbor from below responds first, but the rest gradually connect to it. By three in the morning the whole house is singing.

You put the hammer aside and walk over to the socket.

“You are here,” you shout into the socket.

“We are here,” you shout into the ventilation.

- I'm here! - you shout through the open window so that the windows in the neighboring house also light up.

That's when they launch the apparatus to the moon, then we'll talk.

That's when he sits on Mars, then we'll talk.

Just ten years ago, on September 28, 2008, SpaceX was able to send a satellite into orbit for the first time, using the Falcon 1 light-class rocket. , is building a giant BFR rocket, and in another ten years he expects to have his own habitable base on Mars. The fantastic successes of the company raise a lot of questions: how did it happen that a “private trader” was able to bypass even some well-deserved space powers in a negligible time? And what is the price of Elon Musk's promises to get to the Moon and Mars? Editorial N+1 asked experts - Director of the Institute of Space Policy Ivan Moiseev and editor of the magazine "Cosmonautics News" Igor Afanasiev to explain the rapid development of SpaceX and assess its plans for the future.

Dragon cargo spacecraft during docking with the ISS

Maskophobes attribute SpaceX's success to the fact that the company received funding and technology from NASA. Is that what it's all about?

Ivan Moiseev : NASA paid for the Falcon 9 rocket, as they say, "on the vine." This means that the rocket has not yet been built, and the US space agency has already begun paying money to SpaceX - as part of contracts for the delivery of goods aboard the International Space Station. SpaceX was able to effectively use this money and expand its activities - to receive orders for satellite launches from other countries, from the US military and from telecommunications companies.

Of course, these successes would not have been possible without the technological capital that has been raised in the US to date. And the task of NASA, both then and now, was precisely to introduce the intellectual property that is concentrated at the agency. This was a very big contribution to the success of SpaceX.

Igor Afanasiev: Undoubtedly, external funding from NASA and other government agencies (in particular, from DARPA) in the early (but not early) stages of the development of launch vehicles and spacecraft significantly influenced the success of SpaceX.

However, one cannot discount the fact that Musk started work on the company's money (one might say, on his own) and / or on funds that he managed to raise through external sources and venture funds. And these amounts were measured by six or seven figures and grew from stage to stage. In particular, when developing the Falcon 1 light rocket, Musk understood that his own savings would barely be enough to create a small, relatively simple launch vehicle, and from the very moment SpaceX was formed, it was necessary to establish good relations with government departments - NASA and the Pentagon - that were most interested in research and space exploration.

Having made the first rocket and demonstrated to potential customers the capabilities of his company, Musk secured state support and got the opportunity to build a powerful Falcon 9 on its basis. Following this, SpaceX, armed with a new carrier, became not only another player in the launch services market, but also a powerful development driver rocket and space technology in the United States and around the world.

Shares of companies and countries in the commercial launch market

Tim Hughes, SpaceX

The same can be said about intellectual property. And here we are talking, rather, not about obtaining technologies belonging to NASA, but about specific people with extensive experience in the rocket and space industry. It was these people that Musk sought to get by any means, they were the intellectual backbone of SpaceX.

However, there are also conspiracy points of view, for example, that the Musk “raised and nurtured” NASA (on its own or with the support of the Pentagon) by creating a competitor to the largest aerospace giants of today Boeing and Lockheed Martin, which, from the point of view of a number of experts, “snickered and bite off budget pie too fatty pieces, inadequate to the benefits.

First launch of the Falcon Heavy super-heavy rocket

What is the main technical achievement of the designers of the Falcon missiles?

Ivan Moiseev : I would outline two main achievements, they are a bit diverse.

The first is that they adapted it to the requirements of the market even at the development stage of the future Falcon 9 rocket. In particular, they adopted simple open circuit motors. In these, the generator gas that drives the turbopumps is simply dumped rather than fed into the combustion chamber where it could generate additional thrust.

Such engines are considered obsolete, they are less efficient than those with a closed circuit. But, since they turned out to be cheaper, simpler, SpaceX benefited greatly from this.

Secondly, they developed the return stage. This is already SpaceX's own initiative, this was not done at the expense of contracts with NASA, but this allows the company to save quite a lot on launches - up to 20-25 percent.

Igor Afanasiev: There are several real achievements.

First: the creation, serial production and operation of a two-stage medium/heavy launch vehicle with the highest design efficiency today without the use of oxygen-hydrogen fuel. In terms of the number of stages and the ratio of the payload mass to the launch mass, the Falcon 9 is more efficient than such launch vehicles of a similar class as Ariane-5, Long March-5, Zenit, Proton, and the like.

Second: development of the landing technology and the first stages of reuse of the most expensive and usually lost element of the rocket and space transport system - the multi-engine first stage. If the declared characteristics are confirmed, this may become a trend in modern rocket and space technology.

Third: an exceptionally high rate of launches (not typical for American launch vehicles of the 2010s) and good cost performance, which made it possible to win a significant share of the launch market, squeezing out (or significantly moderating the ardor) of traditional players with their launch vehicles created using technologies 1960–1980s.

Landing Falcon Heavy side boosters

Will reusing the first stages of SpaceX rockets really be cost effective?

Ivan Moiseev : It seems very doubtful to me that the promises that the used first stages will be able, after returning, immediately, almost without preparation, go back into space. Serious checks, tests, preparation for a new launch will still be needed. SpaceX can, of course, cut costs for this, but there are fundamental things that you cannot cut.

But the fact is that even a 25 percent reduction in launch costs is a lot for the rocket industry, this is a very good indicator. If you manage to, say, reduce the price by one percent, this is already serious money, because launches cost millions of dollars, and here it’s 25 at once. And Elon Musk made a revolution in a sense, because the inertia of the developers’ thinking forced them to make the most efficient engines and not very care about the fate of the step. But he did the opposite and got the result.

Igor Afanasiev: The repeated use of the first steps has already been established. True, so far this process has been reduced to the double use of rocket blocks (but soon we are promised something more, with the help of the latest version of the Falcon 9 Block 5 carrier). Has this resulted in real cost savings? It's hard to say - the company (like most launch providers) does not give specific "price tags", you have to either take Musk's word for it, or "figure it out on your fingers", using the proportions indicated earlier by SpaceX officials.

If we assume that the first stage costs 60-80 percent of the entire two-stage Falcon 9 rocket, then with its two-stage use (excluding inter-flight maintenance), launch costs are 60-70 percent of the cost of a similar one-time rocket, with three times - 47-60 percent. The goal of Musk's engineers is to cut costs by orders of magnitude. It will be extremely difficult to do this, taking into account the inevitable appearance during multiple launches of the above-mentioned costs for interlaunch operations, including the repair of worn mechanisms, the restoration of thermal protection sections lost during entry into the atmosphere, the cleaning of soot from propulsion systems, etc. By the way, during the operation of the Space Shuttle system, these costs turned out to be much higher than the developers expected ...

Estimated appearance of the super-heavy rocket BFR

How realistic is the 150-tonne BFR missile project?

Ivan Moiseev : This rocket will remain on paper, like the previous project - the Martian transporter. The thing is, it doesn't have a customer. The development of a rocket of this class, the class of the super-heavy lunar Saturn V rocket, costs tens of billions of dollars, even if it is very economical. Its counterpart, the SLS rocket, has already cost $30 billion.

SpaceX does not have that kind of money, and there is no other customer for this rocket, because NASA in its interplanetary projects focuses on using its own SLS rocket. No customer - no rocket.

Igor Afanasiev: The BFR project is no larger than the Saturn V that has flown for half a century, and in terms of launch weight it is lighter than the Soviet Vulkan carrier that remained on paper, which was supposed to be created on the basis of Energia. The Raptor oxygen-methane engines for the BFR are close in size to the Kuznetsov NK-33 on the Soviet N-1 lunar rocket. Analysts note that the financial side of the project is no longer as hopeless as it used to be and does not cause persistent rejection among potential investors. It is possible that, in a certain scenario, NASA will become interested in the project, because one of the goals of the BFR is to replace the Dragon spacecraft serving the ISS.

Leaving aside the economics of the project, we can say that, in general, there are no particular doubts about the feasibility of BFR (as practice shows, almost any engineering problem formulated that does not contradict the laws of mechanics can be solved). But many questions remain both to the whole concept in general and to the details in particular. It is still difficult to achieve the planned levels of excellence. It is not known what to do with the acoustic loads, which for the first stage BFR are almost twice as high as it was on the Saturn. Increased acoustics forces to strengthen the structure, greatly weighting it. Skeptics note the utopia of the idea of ​​“a universal system capable of landing on the Earth, the Moon and Mars, as well as on all other celestial bodies,” as Musk declares. There are very big doubts about the possibility of carrying out "conveyor launches" - and for the future colonization of Mars, thousands of launches a year are needed!

Many questions are raised by the planned operation of the system, which provides for a minimum of repair and restoration work after BFR flights, or a complete rejection of them and even maintenance. Meanwhile, so far unattended equipment (sledgehammers, axes and other equipment are not considered) has not been realized by anyone - even cars (not to mention aircraft) undergo regular maintenance. It is absolutely incomprehensible how to create a non-repairable rocket aircraft subject to much higher loads?

It is not clear how the issue of emergency rescue of the crew and passengers of the BFR during an abnormal launch is being resolved. Musk reduces everything to an analogy with passenger aviation, where neither the crew nor the passengers have means of escape in emergency and catastrophic situations. If desired, one can find a rational grain in these arguments, but one must take into account that “the history of aviation written in blood” is more than 100 years old, while not a single interplanetary passenger flight has yet been completed (professionals flew to the moon, and for them the risk was everyday phenomenon), therefore, the extension of aviation experience and criteria to deep space flights seems unreasonable.

Ivan Moiseev A: It's pure fantasy. First, who will be the customer of this project? This customer must have money not only for a super-heavy rocket, but also for a ship, and for the entire infrastructure, for the constant supply of this base. In order to land just two astronauts on Mars and return them back (and, remember, Musk plans to send hundreds of people), according to some estimates, $ 500 billion is needed. The largest customer in this area is NASA, with a budget of $20 billion a year. That is, if NASA will deal only with Mars and nothing else, then it will take 25 years to implement this project.

Therefore, all this talk about Mars will remain talk. As soon as they start counting money and asking “who will pay?”, it immediately turns out that there is no one to pay. In addition, the machines work quite well, they transmit a lot of information from Mars, therefore, in the scientific plan, a manned expedition will not be justified. What's the point of having a habitable base if a rover can travel and collect information for years?

Igor Afanasiev: There are too many "ifs" here ... If the BFR project "gets started", if Musk finds the necessary money, if the flight tests of the rocket go at the intended pace, and so on. But judging by how much the timeline for SpaceX's vast program is dragging on compared to previously released plans, most likely not.

But this is natural: in astronautics, each subsequent step is much harder than the previous one, as if climbing a ladder with ever-increasing steepness. Building a giant rocket the size of a BFR is a big step, sending people to Mars is a huge step, and building a base, and even by the end of the next decade, seems like a utopia. In addition, all the main successes of SpaceX over the past ten years are somehow related to solving problems in the interests of government agencies. But NASA plans to land people on Mars (at least for the time being) on ​​its own, although the possibility of connecting "private traders" (consider - SpaceX and, possibly, Blue Origin) at some stage of the program cannot be completely ruled out. Most of the technical aspects of the problem seem to be feasible, although the scale of development is amazing.

Interviewed by Grigory Kopiev

On March 30 at 22:27 UTC, when it was almost half past one in Moscow on March 31, the Falcon- 9ft. For the first time in the history of world cosmonautics, a rocket stage with liquid engines set off on a space mission again (the first flight of the CRS-8 with the Dragon cargo ship took place on April 8, 2016). The SpaceX rocket successfully launched the SES-10 communications satellite into orbit, and the first stage, the “veteran”, made a soft landing on the automatic barge “Of Course I Still Love You”.

⇡ Fears, insurance and launch

The "epochalism" of the event could be assessed by the reaction shown by the electronic and print media. Still would! “Musk is planning (and, according to many, is making) a revolution in the implementation of space transport operations: he reuses a stage in the launch vehicle that has already completed its mission to launch a satellite once, returned safely to earth, was rescued and restored ".

Officially, the main objective of the mission was to launch the SES-10 communications satellite into geostationary orbit. However, everyone understood that with this flight, SpaceX planned to demonstrate the possibility of multiple use of the first stage after returning from space. An auxiliary task was considered to be landing the stage (after completing the main task) on a remote-controlled barge located at sea along the launch trajectory. As a bonus, an attempt was made to save the head fairing flaps.

Veterans of rocket and space technology argued that “the launch customer would never go for the reuse of used materiel, especially in the most stressful launch site.” However, SES S.A. - a global satellite operator headquartered in Luxembourg - not only went, but also with its support allowed SpaceX to perform the first re-launch of a rocket with a real ("live") payload, and not with a mockup, as some suggested.

“As the first commercial satellite operator to fly a mission with SpaceX back in 2013, we are thrilled to once again be the first to re-fly into space,” said SES CTO Martin Halliwell. “We believe that reusable rockets will usher in a new era of space flight, making it more affordable and less expensive.”

After the triumphant return of the 1021 rocket stage almost a year ago, SpaceX experts conducted a detailed analysis of the state of this rocket unit. Their main concern was the engines, eight Merlin-1Ds, gathered in a ring around the ninth, central one. For the reuse of the stages, it was important to have 100% confidence in their serviceability after several cycles of operation, and also due to the influence of thermodynamic loads during re-entry from the ascent trajectory.

Throughout its life - up to this night - the first stage No. 1021 was "tested by fire" repeatedly, and as a result, before the second launch, it had six on-off switching of the propulsion system (three of them - in the first flight).

“We didn’t repair these engines, we just wanted to change some gaskets…,” technicians reported in late January 2017 before fire testing at the SpaceX stand in McGregor, Texas. “But we just removed these engines, tested them, put them back and are burning them right now.”

It should be noted that SES representatives have been involved in the preparations for this launch over the past few months. According to Halliwell, "SpaceX gave the SES engineers ... 'full transparency' in their operations, gave them a glimpse into the preparation of engines and avionics, as well as the test results."

It was also surprising that the insurance premium for the first flight of the "used" stage was not increased, as if everyone understood that the attention to this launch was special and SpaceX put a lot at stake. As a result, the mission's level of preparation will be unprecedented. According to observers, "in terms of design reliability, the carrier will not be much lower than the previous ones."

As for insurance growth, “we can talk about hundredths of a percent,” Halliwell said. “In fact, there has been no change in the insurance premium.”

So, a huge - 70 m high - "pasta" Falcon 9 FT was installed in the launcher on the evening before the launch. The duration of the starting window was 150 minutes. Under the nose fairing of the rocket was SES 10, a communications satellite manufactured by the European consortium Airbus Defense and Space to broadcast television programs and transmit data from geostationary orbit throughout Latin America.

The timeline below describes the estimated launch sequence for the first SpaceX mission with the rocket's first stage already flown, salvaged and recovered.

Nine engines of the first stage of the rocket turned on a couple of seconds before the launch to conduct an automatic performance check. After the test, the holding clips released the rocket, and the Falcon 9 lifted off the LC-39A pad and lay down on the flight path.

Soon the sound barrier and the zone of maximum aerodynamic pressure were successively passed. After working for the prescribed 158 seconds, the first stage engines turned off, and after three seconds the stages separated.

After turning on the only engine of the second stage, when the carrier had already left the dense layers of the atmosphere, a huge carbon-fiber head fairing with a diameter of 5.2 m was dropped.

While the second stage engine was still running, the first stage rolled over, deployed the trellis aerodynamic fins at the front, and braked three of the nine engines for 20 seconds to slow reentry and create a gas-dynamic "bell" around the tail.

The last activation of the central engine for a soft landing occurred just before touchdown: the stage went to a barge located in the Atlantic Ocean about 340 miles (550 km) east of Cape Canaveral. At that moment, the television broadcast was interrupted, but the control room burst into applause when a step appeared on the screen, standing on “legs” on the deck of the drone ship.

At the same time, the second stage was completing its intermediate low orbit. The engine turned off and a short 18-minute passive section of the trajectory began ("ballistic pause").

This was followed by a short inclusion of Elon Musk, who spoke about the "gigantic revolution in space flight" and congratulated his colleagues on the victory that everyone had been waiting for.

Then the Merlin 1D Vacuum started up again and put the rocket into a highly elliptical orbit with an apogee near the geostationary station. The satellite separated from the second stage 32 minutes after launch.

⇡ Debriefing

How historically significant was the re-flight of the rocket stage? Opinions on this issue were divided even before the mission. Someone considered this a breakthrough in launch vehicles, which would drastically reduce the cost of access to space. Someone thought differently, calling the SpaceX experiments "show and circus" that had nothing to do with technical and economic feasibility.

But an objective view presupposes balance. In the history of cosmonautics, the technical feasibility of multiple use of solid-propellant launch boosters in orbital launches (Space Shuttle) and liquid-propellant rocket units in suborbital flights (New Shepard by Blue Origin) has been confirmed in practice. Musk was the first to solve the technical problem of reusing the liquid stage of the orbital carrier, complicated by the fuel components used (when burning kerosene in liquid oxygen, soot falls out in the engine units, causing many serious troubles). This is a significant achievement from a technical point of view.

However, reusability is needed to reduce costs. But here everything is not so clear. SpaceX spent at least four months and an unknown amount of money to repair, restore and test the already flying stage. And reuse makes sense if the cost of "inter-flight maintenance" does not exceed the savings in the manufacture of a new stage. They say that the launch customer of SES-10 cost about $ 40 million - a third less than the standard price tag. This is a special price taking into account possible risks. Whether Musk will be able to maintain this figure while reusing the first stages in regular operation is a big question. Cautious experts predict a possible price reduction by ten percent. And these are not the numbers that will “drastically” reduce the cost of space launches. In other words, Musk has proved the technical feasibility of reusing rocket technology, but the economic feasibility has yet to be proven.

Nevertheless, Halliwell said in advance that if this launch is successful, his company will be able to launch two more satellites - SES 14 and SES 16 - on previously used boosters later this year. "The next vehicle assigned to SpaceX, SES 11, will fly this summer on a recently launched rocket," he said.

In addition, according to him, the transition to reusable missiles is unlikely to be canceled even in the event of an accident.

⇡ Comparison

To better understand what new heights Musk has reached, let's take a closer look at the possible options for rescuing the lower (first) stages of launch vehicles. To date, three main methods have been studied in some detail:

1. Vertical parachuting (if necessary, using soft landing rocket engines at the last stage).
2. Horizontal gliding using wings or gliding parachutes.
3. Vertical jet landing on main or auxiliary rocket engines.

The main advantage of these methods can be considered that they allow you to create a system (lower stage) with multiple use of the material part as part of the rocket and space complex, and this reduces the cost of launching the payload by two to three times (depending on the frequency of use).

The main disadvantages of the methods are reduced to complicating and increasing the cost of developing, manufacturing, testing and operating the stage, increasing its “passive” mass, which as a result can lead not to a fall, but to an increase in the unit cost of launching a payload.

⇡ Parachute and parachute-jet landing

To date, it has been successfully implemented only in the Space Shuttle system for the return of starting solid-propellant boosters during landing on water, and was also considered to save the side blocks of the first stage of the Energia launch vehicle (not brought to practical implementation). Attempts to rescue the first stages of the Falcon-1 launch vehicle using a parachute were unsuccessful. We should also recall individual experiments to rescue the boosters of the Ariane-5 launch vehicle. Theoretically, the method of helicopter pickup of the parachute blocks of the Angara launch vehicle was studied.

Advantages of parachute landing:

1. allows using the earth's atmosphere to dampen the residual velocity after separation of the first and second stages;
2. relative ease of implementation for robust and stable systems such as solid-propellant boosters;
3. relatively small mass costs for them.

Flaws:

1. large areas of domes, the regular opening of which turns into a problem that is difficult to solve when the mass of returned cargo (in this case, spent stages) is more than 20-30 tons;
2. the impossibility to ensure accurate landing due to the effects of wind and other atmospheric disturbances, as well as the lack of active landing control (for disk and canopy parachutes);
3. relatively large mass costs for fragile liquid rocket blocks due to the need to install additional means (soft landing engines, landing legs, stiffening elements) to dampen speed and overload at the last stage of landing. Thus, for block A of the Energiya launch vehicle, the mass of rescue and landing means was a significant part of the final mass, which led to an increase in the cost of developing and building the system. Block A in a one-time version without means of rescue had a mass 60% less, in addition, the cost of a reusable block A in 1990 was 18 million rubles, while the launch of a Zenith launch vehicle, including a one-time analogue of block A, cost not more than 6 million rubles;
4. high g-forces during braking in the atmosphere, at the moment of putting the parachute system into operation and at the moment of touching the surface (in the absence of soft landing engines);
5. lack of guarantees for the safety of the structure (especially fluid blocks) during landing due to the impossibility (or extreme difficulty) of ensuring zero vertical and horizontal speed and, accordingly, the presence of shock loads;
6. when landing directly into the water - relatively large shock loads and a high risk of corrosion of structural elements;
7. great difficulties in transporting large-sized long stages from the landing site to a repair plant or spaceport.

⇡ Planned landing

At present, a horizontal gliding landing at the airfield using a relatively high aerodynamic quality has been implemented on the winged orbital stage of the Space Shuttle, on the Buran orbital ship and on the Kh-37 experimental rocket plane. In numerous projects of the 1960-2000s, this method was considered as the main one.

Advantages:

1. allows you to use the atmosphere not only to dampen residual speeds, but also for maneuvering (within certain limits) along the longitudinal and lateral range to select a landing site with minimal fuel consumption;
2. ideally, it is possible to return and land in the launch area, which reduces the cost of search and rescue and transport operations;
3. high landing accuracy (within the runway) due to the presence of aerodynamic controls;
4. low overloads during braking in the atmosphere (approximately 1.5-2 units);
5. low shock loads during landing (vertical speed of about 3 m/s can be absorbed by landing gear dampers).

Flaws:

1. high complexity and cost of development, production, testing and operation due to the presence of aircraft systems and units (wing, tail, landing gear, auxiliary engines, aerodynamic controls, complex hydraulic system, etc.)
2. large bulkiness and high mass costs due to the presence of aircraft systems (up to 25-30% of the final mass of the rescued block);
3. operational restrictions are possible (limits on the program for changing the angles of attack during launch and on the atmospheric launch leg, as well as extremely accurate compliance with the atmospheric entry parameters and wind speed restrictions along the return route and at the landing site);
4. the impossibility of entering the second circle of a horizontal landing (to realize such a chance, it is necessary to equip the return unit with an auxiliary propulsion system and a supply of fuel, which further increases the "inertial" mass);
5. the need to strengthen tanks and other compartments (leads to an increase in the final mass of the block), associated with high transverse loads, which are not typical for disposable rocketry.

⇡ Vertical jet landing

To date, jet landing has been sufficiently worked out on the first stage of the Falcon 9 launch vehicle (SpaceX) and the NewShepard suborbital system (Blue Origin), as well as on landers of interplanetary (mainly lunar) probes and experimental aircraft of the DC-X type. and Grasshopper. Jet landing on auxiliary turbojet engines was considered in the project of the Podyom reusable rocket and space system of the enterprise, which is now called the Progress Rocket and Space Center (RKC), Samara.

Advantages:

1. relatively low cost of development and production, since the main mass costs fall on the cheapest component of the system - rocket fuel;
2. the possibility of limiting overloads during braking in the atmosphere;
3. the possibility of precise landing, including in the launch area (reducing the cost of search and rescue and transport operations);
4. low landing loads (near zero speed) and low lateral loads during atmospheric descent;
5. low losses in the mass of the payload during landing in the area of ​​the regular fall of the block (or on the landing platform in the ocean) - from 5 to 15%;
6. the possibility of using the rocket block both in reusable and disposable versions (expanding the flexibility of operation).

Flaws:

1. poor use of the earth's atmosphere to dampen residual velocities;
2. increased requirements for the control system (in fact, technologies were used that are more characteristic of modern high-precision weapons than rocket and space systems);
3. complication of the rocket block due to the installation of additional systems (auxiliary rocket nozzles or engines, aerodynamic controls, landing legs);
4. high loss of payload mass when the stage returns to the launch site (up to 30-50%);
5. restrictions on operation (first of all, wind speed and direction along the descent route and at the landing site);
6. tightening requirements for the propulsion system (the need for quick multiple automatic start in flight and the possibility of deep throttling of thrust during landing).

⇡ Will we wake up tomorrow in a new world?

Now, after the impressive successes of SpaceX and Blue Origin, according to some experts, in terms of operating costs of the entire system, a vertical jet landing looks preferable. However, the choice must be made on the basis of repeatedly confirmed examples, supported by real cost figures.

For example, the success of this method, demonstrated by Elon Musk's company, is largely due to the possibility of a simple, fast and cheap delivery of a dead stage by a self-propelled vessel to a coastal American spaceport: the declared minimum loss in payload mass is combined with minimal costs for search and rescue and transport operations. In the conditions of "continental" spaceports (Vostochny, Baikonur, Plesetsk), landing in the taiga or in the desert in the absence of transport infrastructure may turn out to be unacceptable, and the return to the launch site may be the only possible one. In this case, the aircraft method may become more profitable (due to lower losses in the mass of the payload).

When launching rockets from continental spaceports, landing a reusable stage on rough terrain is unacceptable

Combined return methods are possible (and are widely considered), including, for example, the use of the aerodynamic quality of the entire stage in the braking section in the atmosphere in combination with a parachute-jet landing of a block separated from the tank compartments with the most expensive and complex equipment - sustainer engines and a control system.

In any case, it should be noted that the currently existing criteria for the development of disposable launch vehicles are apparently unacceptable (or require significant adjustment) when creating reusable rocket and space systems, even including one (first) stage with a vertical jet landing.