Roscosmos criticized Elon Musk's ship: what is wrong with this criticism?

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Roscosmos criticized Elon Musk's ship: what is wrong with this criticism?
Roscosmos criticized Elon Musk's ship: what is wrong with this criticism?
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The Russian space corporation has named three problems with SpaceX's Crew Dragon. However, a close examination of these problems reveals the unexpected: they are not all problems. What exactly makes the Russian space corporation invent flaws for its main competitor? Oddly enough, the point is not even that he pushed Russia out of the launch market. The real reason goes much deeper. Let's try to figure out the details.

Crew Dragon

The June issue of the magazine "Russian Space" - the departmental magazine of "Roscosmos" - could not pass by a really major event: the first launch of a spacecraft of a private company with people on board. But he did it in a very strange way.

First, I tried to find flaws in Crew Dragon - which in itself would be nice. After all, as soon as we find flaws in something, the opportunity to eliminate them immediately appears. Unless, of course, we are talking about real shortcomings. Secondly, the magazine published a column dedicated to the same ship of Elon Musk, in which the head of Roskosmos made a number of statements.

It can be seen from this that the psychological reaction of the Roscosmos leadership to the launch of the manned Dragon was very sharp. At first glance, this seems incomprehensible: as we already wrote, the new ship does not threaten Russia's interests in space specifically (unlike SpaceX's Starship). Let's try to understand what is the matter.

Why Crew Dragon's rescue engines are dangerously close to the crew

The departmental magazine notes: in the SpaceX spacecraft, the engines of the emergency rescue system are located right behind the wall of the manned section of the ship. This, he said, is "alarming."

“A number of specialists,” continues “Russian Space”, doubt the safety of the proximity of the crew and a couple of tons of toxic fuel (monomethylhydrazine) and an oxidizer (nitrogen tetroxide). The question arises: how bad is this for the safety of American astronauts?

Emergency rescue systems (SAS) have existed in spacecraft since the 1960s. They are launched if suddenly something went wrong with the rocket - at the start or already in flight. The SAS engines raise the capsule with the crew to a considerable height (if an emergency has arisen on the launch pad), after which the capsule's parachutes open and it lands. If the SAS had to be triggered already in flight, it separates the capsule from the rocket, takes the first one to a considerable distance from it and activates the parachutes there.

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It seems to be obvious that the safest scheme of the SAS is about the same as on the Soyuz or Apollo - in the form of a detachable structure on the nose of the spacecraft, so that the SAS fuel would be away from people. And even with engines on components that in the event of an accident will be non-toxic - and in the SAS of both ships from the 60s, solid rocket fuel is used, and not at all monomethylhydrazine (rather toxic), like SpaceX's Crew Dragon.

However, if you see someone's seemingly obvious mistake, it sometimes makes sense to think: Do you really understand what you see well? SpaceX clearly knows how to design spacecraft, otherwise it would not perform more commercial launches per year than Roskosmos. What made Musk place the SAS engines not in the detachable nose turret, but on the sides of the capsule with the astronauts? And even on engines with toxic fuel?

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Garrett Reisman, a SpaceX consultant and former NASA astronaut, explains it simply: the "push" solution (the engines on the sides of the capsule itself) is safer than the "pull" solution (the engines in a detachable turret on top of the capsule with people).

There are two reasons for this. First, the detachable turret with SAS engines, even by pulling the capsule aside, in the event of an accident, the missile may not separate. Yes, oddly enough, there are disruptions in the space industry. Even the Russian Soyuz launch vehicles, the safest and most tested means of launching people into space, sometimes fail in the correct separation of the stages - and in the same way, a non-separation at the SAS turret may one day happen.

And in this case, it will not be possible to save the astronauts in the ship: after all, the parachutes will go up and have serious chances not to turn around normally due to the undivided turret. Then the capsule will stick into the surface of the planet and kill its crew.

But there is a second reason: the flexibility of an emergency rescue system without a turret increases significantly. On the way up, an ordinary spacecraft (for example, the Soyuz) is forced to shoot off the turret, which represents extra weight for it and creates unnecessary resistance. This means that the ship does not have SAS engines from a certain height. If something goes wrong, he will be forced to descend by parachute. That is, not really choosing the landing point.

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In the history of Russian cosmonautics, there have already been cases of landing in areas where our spacecraft did not plan to land. These are very dangerous and unpleasant cases. In 1975, during the launch of the Soyuz-18-1 spacecraft, some of the locks of the booster's stage compartment did not work: the stages separated abnormally, which is why it did not go into orbit, but parachuted down to where it was not planned.

Namely - on the snow-covered slope of Mount Teremok-3 in East Kazakhstan. The ship, naturally, began to roll down the slope and would have killed both cosmonauts, if not for a happy accident: the parachutes got stuck in the vegetation, and the Soyuz stopped 150 meters from the cliff. A sacramental question: what would happen if the ship fell a little higher, where there is no serious vegetation?

We had another fatal landing in an unplanned location in 1976. The Soyuz-23 ship hit Lake Tengiz, falling a couple of kilometers from the shore. At first, the exit hatch was under water, and the astronauts were locked inside. Then the water caused the release of reserve parachutes, from those "Soyuz" tilted and the water blocked the ventilation holes. There was no supply of oxygen for such a time on the spacecraft - and one of the two cosmonauts lost consciousness from suffocation.

They tried to pull the cosmonauts or tow them to the shore with the ship. But there was a blizzard and minus 20 ° C, which made it impossible for a long time. Fortunately, the storm died down and the people were rescued (however, one of the rescuers lost two fingers from frostbite). What would have happened if the weather had not improved?

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From this it is obvious: an emergency rescue system integrated into a ship is much better in the future than a detachable one. American ships land in the ocean, which means that they must get into a non-storm zone (otherwise, problems similar to the incident with Soyuz-23 may arise). But there are extremely few moments in the Atlantic when there are no storms along the entire trajectory of a possible fall of American spaceships.

But SAS Crew Dragon, due to its inseparability, can be used in any part of the ship's flight - even where, like the Soyuz-18-1, the usual tower rescue system would have already been separated.

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Thanks to the built-in CAS, the SpaceX ship can adjust its trajectory up to 370 kilometers - exactly where the Crew Dragon computer points. That is, to the desired area with a minimum wave force and / or a minimum distance from the coast. After the above examples with "Soyuz", it is obvious: this is an important feature that really increases safety.

Why SpaceX chose toxic fuel

Well, why integrate rescue engines into the Crew Dragon hull is understandable.But why choose for it not solid-fuel engines, but liquid ones - on the dangerous monomethylhydrazine?

Indeed, the engines of the SAS "Soyuz" or the old "Apollo" are solid-fuel, their contents are relatively non-toxic. But you have to pay for everything: solid propellant engines are, in fact, powder bills of a complex composition. The strength of their combustion is almost impossible to regulate. This means that they give a much lower accuracy when landing a ship.

The Crew Dragon emergency rescue system consists of four pairs of Super Draco engines, each of which can vary its thrust from 20 to 100% of the maximum. By giving more thrust to some pairs of these engines and less to others, it is possible to deviate very strongly the flight trajectory of the apparatus in the upper layers of the atmosphere and land exactly where it is necessary.

With solid-propellant SAS engines, this is basically a dream. That is why Soyuz-18-1 played bobsleigh on the slope of a difficult mountain, and Soyuz-23 played a submarine in the middle of the Kazakh steppes.

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There are other reasons why SpaceX chose liquid propellant rocket engines for the emergency rescue system. In an ordinary spacecraft (the same "Soyuz"), the SAS is separated in the atmosphere and does not enter space. Crew Dragon always has it with her. Therefore, in orbit, being docked to the ISS, the emergency rescue system is subjected to strong heating and cooling 32 times a day for many weeks.

Solid propellants are not designed for these operating conditions. What happens if it catches fire in orbit? But monomethylhydrazine does not care: it and its oxidizer can easily tolerate such temperature drops while being in sealed capsules.

Incidentally, this is one of the reasons why Russian Soyuz spacecraft also use toxic fuel (dinitrogen tetroxide and asymmetric dimethylhydrazine) for maneuvering in orbit, albeit to a lesser extent than Crew Dragon.

Another important point: even if the solid fuel SAS does not ignite in orbit, it will have to be changed upon returning to Earth. SpaceX's concept is precisely in the reusability of the ship - and as many of its subsystems as possible.

But what about the crash of Crew Dragon in April 2019, when the emergency rescue system fuel caused a fire and explosion due to a leak from a valve? Here you need to understand: new systems in space without explosions are rarely obtained. But such incidents provide valuable experience that is taken into account when modifying ships and missiles.

And SpaceX was quick to learn from the explosion of last year. The emergency rescue fuel can no longer leak through the valves - since on the Crew Dragon it now only comes into contact with the diaphragm relief devices.

Because of this, the phrase of an article in Russian Space is surprising: "Last year's [Crew Dragon] explosion at the ground stand underscores the validity of these doubts [about the dangerous SAS fuel of the new ship]." After all, the system now takes into account past mistakes, which means that doubts could only be fully justified regarding the test prototypes of the Crew Dragon, and not the current manned spacecraft.

Conclusion: the fact that the new emergency rescue system is called "revolutionary" is justified. It will indeed allow ships to land in case of difficulties much more accurately than before, which will significantly increase the safety of people on board. Concerns about such a CAS are based in large part on not knowing why SpaceX chose it.

Among other "problems" of Crew Dragon, an article in "Russian Space" calls oversize: they say, the developer calculated the spacecraft for seven people, and NASA, due to lack of funds for the crowded crews of the ISS, insisted on setting only four seats.

But is this a problem with the ship? We are not even talking about the fact that SpaceX may well start flights not only in the interests of NASA (especially in the options when the Agency itself will stop regularly flying to the station). And then nothing prevents the Mask from putting more chairs there.

Why Crew Dragon actually became the first private spacecraft

Following the technical - and, as we have shown, not entirely justified - claims against Crew Dragon, the same departmental magazine gave a column entitled "Debunking Myths".

It begins with an extremely interesting thesis: "Contrary to popular belief, the head of SpaceX built the ships not with his own money, but at the expense of American taxpayers."

There is only one problem with him: we did not manage to find a single media outlet that would ever write that the head of SpaceX was building ships "on his own money." All publications that generally touched on this topic noted that SpaceX began to make, for example, a giant Starship ship with its own funds, but about Crew Dragon, everyone states that this is a project paid for by NASA, and no one writes otherwise.

However, let's leave this and turn to the easily verifiable thesis of the column:

“The Vostochny cosmodrome, built in the Amur taiga, eight hours flight from Moscow, in a region where there is neither the necessary labor force, nor construction equipment, nor logistics centers (all this had to be imported and created in the Far East), costs 2, 5 times cheaper than this supposedly private American ship."

The fact is that the cost of the Vostochny cosmodrome, by any estimate, is not less than two billion dollars. That is, either $ 5 billion was allocated for Crew Dragon, or the quoted statement is not entirely correct.

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All expenses for Crew Dragon for 2019 according to NASA audit - $ 1.2 billion. Another 1.3 billion have been promised for future flights to the ISS, but they cannot be counted in the cost of creating the "supposedly private spacecraft" itself: flights to the ISS include, for example, the cost of Falcon 9 rockets that support the flight. The final planned cost of the R&D program specifically for the creation of Crew Dragon is $ 1.7 billion.

This is significantly cheaper than the Vostochny cosmodrome. But not only him. The Starliner, a Boeing spacecraft, cost NASA $ 2.8 billion (and this despite the fact that it does not fly yet), and the Orion spacecraft cost $ 23.7 billion. SpaceX has given the US the cheapest spacecraft in its history.

The interesting theses of the column do not end there. They report: "No less strange is the statement that" for the first time a private company has created a manned spacecraft. " Did Boeing and Lockheed Martin stop being private and nationalized by the US government?"

Recall that both Boeing and Lockheed Martin are public companies, that is, those whose shares are actively traded on the market. They are not directly managed by their owners, so they are not private companies.

The difference between a private company and a public one is that the head of a private company (since he is not limited by shareholders in any way) can force his engineers to do what he sees fit. For example, Elon Musk forced his engineers to put the first stage on the tail, or use supercooling of fuel components, or use stainless steel instead of aluminum. And in a public company like Boeing and Lockheed Martin, this is impossible. The owner of the company simply cannot point out to its employees over the heads of the board of directors. This is why their ships and rockets are significantly, radically more conservative than privately owned SpaceX.

Even the American economist J. Galbraith pointed out half a century ago that joint-stock public companies are essentially not much different from state property: they are also managed not by owners, but by hired employees (salaried directors). And therefore, they show exactly the same inflexibility in the fast-growing markets.

But the matter is not only in the form of ownership and the differences generated by it between a private company and a public one. The technical side of the problem is also important: neither Boeing nor Lockheed Martin have and have never had their own manned spacecraft on which people fly. SpaceX was indeed the first here - before it, the same Boeing and Lockheed Martin only carried out NASA orders according to NASA specifications, and these ships belonged to NASA.

Crew Dragon was conceived by SpaceX, not NASA - and that is why on it, for example, the emergency rescue system is integrated into the ship, and does not remain in a detachable turret, like the Orion spacecraft, created by order of NASA by American public (and not private) aerospace companies …

Why look for a black cat of imperfections in a dark room where it may not be

So, we have established that the theses of "Russian Space" regarding the Crew Dragon from SpaceX contain some omissions and inaccuracies. Moreover, those about which the authors of the relevant theses could hardly have been unaware.But why say something that contradicts your own earlier statements?

Most likely, the reason for trying to find weaknesses where they may not exist is rather commonplace. For many years, Roskosmos has been telling us that SpaceX's reusable solutions have no obvious economic sense, reusable steps do not make it cheaper, landing on the tail is pointless, and so on.

Recently, as we already wrote, Roskosmos itself approved the terms of reference for a rocket landing on its tail. Methane engine development has begun again - clearly reflecting the success of SpaceX's methane Raptor in testing.

In other words, the Russian space agency finally took SpaceX's decisions seriously and took up the challenge. So far, we are only at the beginning of this path, but in the coming years Roskosmos will have to copy SpaceX solutions much wider than today. And this, undoubtedly, can only be welcomed.

But this path has more than advantages. Let's imagine ourselves in the place of a Russian space corporation. For years, in response to questions from our superiors about the success of SpaceX pushing us out of the market, we told them stories that the reusable first stage was pointless. That Musk's decisions are questionable and unsafe.

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Now the effectiveness of these solutions has become so obvious that we ourselves are copying these "dubious ideas." If not today, then tomorrow the bosses will ask us: "Why did you just laugh for eight years and did nothing to react to a competitor?" What is left for us, how not to look for flaws in SpaceX, relying on the fact that the authorities are not aware that in fact the integrated SAS increases safety, and does not reduce it?

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