During her lecture at the 70th International Astronautics Congress (IAC) in Washington DC, Gwynne Shotwell, SpaceX’s COO, talked about how the Starship could help the Artemis program. SpaceX hopes the Starship will reach orbit next year. Then it will be able to conduct missions towards the Moon from 2022. The purpose of these flights will be to take cargo to prepare the arrival of astronauts on the surface of the Moon. The calendar is very ambitious, as always with SpaceX.
Starship : security alert ?
At the conference at the end of September, Elon Musk spoke of manned flights on the Starship within a year. This seems unlikely as there are problems to solve before, and security is one of them. SpaceX did not communicate on the Starship Escape System during the different phases of the flight. Given the architecture presented, there is not really. The thrust / weight ratio of the Starship is not high enough to allow it to deviate quickly from the Super Heavy booster in case of a problem, even by simultaneously turning on the six Raptor engines, because these engines need several seconds turn on and ramp up. This is not really the ideal scenario in case of a problem.
It is reminiscent of American space shuttles, where there was absolute trust in the system. Many deaths are due to American space shuttles. Elon Musk may be hoping that the Starship’s security will be high, with a level of reliability similar to commercial aviation. There are no parachutes or ejection seats on the tens of thousands of Airbus and Boeing planes that fly every day. SpaceX could be expected to develop a system dedicated to take-off, such as a capsule on one side of the Starship where the crew would take their place with a few SuperDraco engines to leave quickly in the event of a problem.
But before asking all these questions, it is already necessary that SpaceX manages to fly men safely in his space capsule Crew Dragon. The experience may help to design an effective security system for the Starship.
Starship and Super Heavy have been detailed by SpaceX
Space enthusiasts are accustomed to presentations of grandiose projects : giant launcher, nuclear engine, Martian base or orbital city… We can dream what would be possible with a strong political will and an unlimited budget. So far, these dreams of spatial expansion are limited to feasibility studies and some 3D representations. But the reality remains implacable. Space is incredibly difficult and expensive.
Only 3 years passed between the revelation of the project and the prototype of the Starship
In September 2016, SpaceX communicated about a super launcher called the Super Heavy, and a crewed spaceship called the Starship. This architecture is designed to allow humans to colonize the planet Mars with, as usual, a few 3D renderings to make dream the eternal optimists that we are. We could expect things to stay there, a nice touch of communication to flatter the image of the company. But SpaceX is really special.
Three years later, a prototype of the Starship stands up in the city of Boca Chica in Texas. In one or two months, it must begin atmospheric flight tests. Elon Musk’s company is therefore slowly convincing us that it is really going to launch this crazy project. This is not the first time that SpaceX realize a wacky announcement of its creator. Ten years ago, nobody believed in reusing boosters by landing them vertically, but today is a routine exercise for SpaceX. This is what gives credit to the Starship project.
SpaceX is now a mastodon of the space industry, which in a few years has become the world leader in commercial launches. SpaceX is now a financially strong player working closely with NASA and the US Air Force. This success is fairly recent but the idea of a huge interplanetary vehicle is studied in the design offices of the company since a long time.
The development of the Raptor engine is at the heart of the development of the Starship
We can thus remember the date of March 2012 when the word “Raptor” was first disclosed to the public. Raptor is a very special rocket engine. It is powerful because it has to propel a super heavy launcher. It burns methane, which should allow it to be reusable a lot of times with minimal maintenance, but also because it is possible to produce methane on the planet Mars. It was therefore thought from the beginning with a clear objective in mind. Finally, it is an engine based on a cycle called FFC (Full-flow staged combustion).
A rocket engine burns propellants (here methane) and oxygen, in a long controlled explosion to achieve the thrust required for spaceflight. Hundreds of kilos or even tons of propellant must be injected every second into the combustion chamber of the engine. This is achieved by using very powerful pumps. Usually, these pumps operate by burning a small portion of the propellants in a secondary combustion cycle. The gases resulting from this secondary cycle are then rejected without participating in the propulsion effort. Losing gas to drive the pumps generates ultimately a less efficient launcher. Other engines like the US Space Shuttle’s RS-25 managed to minimize these losses, but the Raptor engine is the first operational engine to be able to completely eliminate them.
The engine actually uses three combustion chambers. The first two are used to drive the turbopumps. They work with incomplete combustion. One is overloaded with methane while the other is overloaded with oxygen. All propellants go through this step before reaching the main combustion chamber. Incomplete combustion products are then burned to provide engine thrust. It is a very complex process but very effective because no gas is lost. Each gram of methane and oxygen in the tanks can be used directly for propulsion. In reality, the gain in efficiency is about 2% but when you try to reach the orbit, 2% is huge.
SpaceX worked on the Raptor engine for more than seven years, but they achieved a satisfactory result a few months ago. Although it still needs improvements, the Raptor engine is now operational. It even flew successfully on the demonstrator of the Starship, called Starhopper. SpaceX therefore has the cornerstone that will allow it to develop its interplanetary spacecraft. It will, however, have to produce a lot of Raptor engines. SpaceX hopes to make them in 12 hours by the end of 2019. The engine is very powerful but it will take tens of them to lift the Starship and the Super Heavy booster. To create an interplanetary spaceship and its booster implies to think big, very big.
Elon Musk gave details on the architecture of the Starship
Last Saturday, Elon Musk gave a talk detailing the architecture envisioned for his giant spacecraft. True to the SpaceX philosophy, the reuse and economic efficiency are at the heart of the thinking. The vehicle is divided in two parts. The takeoff is done thanks to a gigantic booster which broadly resumes the role of the first stage of the Falcon 9. It must manage the first minutes of flight before returning to land near its launch site. With 9 meters in diameter and 66 meters high, it will embark 3300 tons of propellant to power its Raptor engines. On takeoff, they must provide a thrust of 72 mega-Newton. That’s twice as much as for the Saturn 5 rocket.
6 landing feet and 4 articulated grilles must allow it to control its descent and to land. The Starship takes place directly on this first stage. The Starship has the same diameter of 9 meters and a height of 50 meters. It will be powered by 6 Raptor engines optimized for flight in atmosphere in central position, and able to rotate 15 degrees, and 3 other Raptor engines optimized for flight in space vacuum, which will be fixed. The Starship is expected to embark 1200 tons of propellant, which means that the system as a whole is expected to approach 5000 tons, or 2000 tons more than a Saturn 5 rocket.
Thermal protection is an important issue for the Starship
So it’s basically the same architecture that was presented to us three years ago, but when we go into the details we notice that a lot has changed. During the September 28th presentation, Elon Musk emphasized the manufacturing material of the Starship and of the Super Heavy. They will be made of stainless steel. SpaceX first focused on carbon fiber composites, a lightweight yet robust, but expensive material.
Stainless steel has the advantage of being very resistant to extreme temperatures. Its mechanical properties are even reinforced at high temperatures. That is ideal when you build a space vehicle that stores cryogenic propellants and then rubs to a high-speed atmosphere. Its melting temperature is also very high. Stainless steel 301 can be purchased for around 2% of the price of carbon fiber composites. It is easy to work it and solder it, allowing SpaceX to continue its policy of fast iterations.
The iterative method of SpaceX has been applied to the development of the Starship
Rather than creating a very advanced and expensive Starship prototype, SpaceX prefers to make several of them quickly by continually testing new enhancements. This is exactly the philosophy that has allowed the Falcon 9 rocket to progressively become a finished product. In addition to the Starship prototype that is in Boca Chica, the Mk1, another Starship is being built in Florida. SpaceX is already planning several additional prototypes of the Starship until the company is able to reach Earth’s orbit.
The Starship’s design evolves
Although the overall shape of the Starship remains the same, there are however some design changes in the new architecture presented by Elon Musk. The most obvious are the fins. We used to see 3 fixed wings that were also used as feet. The new Starship has six separate feet and two main fins that are movable. 2 other smaller fins are attached to the top of the spaceship. Together, these four surfaces must be able to control the fall of the Starship into the atmosphere. They allow to perform rolling, pitching or yawing maneuvers. The Starship will spend most of its atmospheric reentry on the belly. This part of the spaceship will be particularly exposed to friction and therefore to heat. The constraints are such that the melting point of stainless steel 301, which is 1400 degrees Celsius, will be reached. The Starship therefore needs additional thermal protection.
Earlier this year, Elon Musk had mentioned an active perspiration system, which has since been set aside. Instead, the Starship will use traditional ceramic tiles. This is reminiscent of American space shuttles. The space shuttle ceramic tiles required very careful inspection and maintenance, which is not compatible with a project that must be economical first and foremost. Elon Musk insists that the thermal resistance of the stainless steel 301 makes it possible to use lightweight and easy to maintain thermal tiles. To land, the Starship must go back and turn on its Raptor engines, like the Falcon 9. Before thinking of an orbital return, there is still a long way to go.
The Starship Mk1 will target the Earth’s orbit, but this will only be the beginning of the challenges to be overcome
The Starship Mk1 is only a rough approximation of what should be the successful spacecraft. It has a dry weight of 200 tons to reach the capacity targeted by the company, that is to say to place a payload of 150 tons in low orbit. They will have to made the following models closer to 120 tons instead of 200 tons. SpaceX hopes to simplify the manufacture of the circular steel segments that make up the hull. They will be welded in one point and the thickness of the sheet will be refined. Elon Musk hopes that the Mk4 or Mk5 version of the Starship will be able to reach Earth’s orbit. For this, he will also have his booster. In all, a hundred Raptor engines will be needed for these tests. That’s why SpaceX wants to make one a day.
Once the Starship is in Earth orbit, there will still be a lot of work to make it a commercial vehicle. A travel towards the Moon or towards the planet Mars needs a series of refuelings by other Starships modified for the transport of propellants. Transforming everything into an inhabited spaceship is yet another important challenge to overcome, even for SpaceX. 9 years after the first orbital flight of its Dragon space capsule, its inhabited version called Crew Dragon has still not sent humans in space.
Elon Musk, always optimistic, could again surprise us
All these difficulties do not prevent Elon Musk from sticking to his famous wacky calendars. He hopes the Starship will reach Earth’s orbit within six months and send humans into space within a year. Even if we don’t believe such promises, we have to admit that the project took on a new dimension in the last 12 months : a FFC methane engine taking off, a full-size prototype that is about to take off, another under construction … We were used to talk about the Starship with “if”, now we start to say “when”. But the adventure could run out without financial support. Without NASA’s collaboration and the financial support of its customers, the Starship could become a new chimera in the history of pharaonic space projects.
Starship’s design evolves, pending Saturday’s conference
– News of September 24, 2019 –
The conference about the Starship’s new architecture is scheduled for Saturday, September 28th. Meanwhile, the prototype Starship Mk1 seems to evolve because the latest photos from Texas show that large wings have been attached to the body of the spaceship. This gives a good idea of the architectural choices that have been made.
So far, the 3D visuals showed the Starship equipped with three wings in a low position that also were used as feet, and two additional wings in the upper position. The latest photos of the prototype of the Starship and some tweets from Elon Musk indicate that there will be two wings in the lower position. They will not have to support the Starship, so the vehicle will use separate feet. This solution is apparently the one that will best support the dead mass of the Starship. This is the option chosen for the first prototypes of Starship, but the CEO of the company remains open to a different solution in the future. These large wings as well as the two wings that will be installed at the Starship’s nose must be capable of extremely fast movements to control the atmospheric reentry of the spaceship. The take-off and landing will be done thanks to three Raptor engines that have just been installed on the prototype of Starship.
To complete the Starship Mk1, it remains to put the nose, which should be done on September 25th. It is not limited to an aerodynamic role because in addition to the mobile wings it accommodates altitude control systems, pressure tanks and large electric batteries. This should counterbalance the mass of engines and large wings at the bottom of the prototype. Eventually, we believe that the upper part of the Starship will accommodate the payload, the pressurized compartment for passengers. If the external architecture of the Starship seems to arrive at its final form, we imagine that there is still a lot of work to do on the side of the internal architecture.
Progress on this prototype seems in any case sufficient to convince his first official passenger. The Japanese billionaire Yusaku Maezawa had announced to participate in an expedition around the Moon in 2023. For this, he has already signed a very big check to SpaceX for the development of the Starship. We learned last week that the eccentric art collector has just resigned from his position as CEO and sold for more than $ 2 billion worth of shares. The goal of the billionaire is to free time and money to focus on his lunar adventure. We do not know the details of the contract that binds him to SpaceX but it is possible that at least some of this money will be used to develop the Starship.
A few months ago, Elon Musk estimated it would take between $ 2 and $ 10 billion to develop his interplanetary spaceship. We are probably still far from this amount but prototype after prototype, SpaceX seems to convince more and more people. For example, NASA has begun to show some signs of interest. Over the last 12 months, the development of the Starship has progressed at a blazing speed.
The prototype of Starship sustained damage during test flight
– News of September 15, 2019 –
A few weeks after the Starhopper flight, some more details were released. If the flight as a whole went well, the prototype of the Starship suffered some damage. We saw that one of its feet had lost its base after contact with the ground, and that the wiring of the demonstrator has suffered.
A pressured fuel tank was also expelled during the flight. There are also many comments on the color of the flame just before landing because it has turned yellow. This indicates a change in the combustion mixture, but we don’t know if this change is voluntary or not.
Obviously, the Starhopper is solid because it could withstand these few damages. But the Starship is thought to be a reusable vehicle without maintenance. Once placed on the Moon or on the planet Mars, the crew must be able to take off after refueling. But if their spaceship loses fuel tanks and burns its wiring, there is a risk of complications.
SpaceX teams will of course use this data to try to reinforce certain aspects of the Starship and to prevent the following models from suffering such damage. This is the purpose of a demonstrator. We will see in what state the Starship Mk1 will return after its inaugural flight, especially as it will undergo much greater constraints.
SpaceX tests the Starship’s heat shield tiles, Elon Musk evokes a gigantic spacecraft
– News of September 3, 2019 –
Pending the revelation of the new design of the Starship, we have seen heat shield tiles designed for the Starship on a Dragon space capsule. It flew on July 25, 2019 with Mission CRS-18. The CRS-18 capsule has since returned to Earth, and it seems that the heat shield tiles have weathered the shock of the atmospheric reentry.
There are still many elements of the Starship to develop. One of the key elements of the architecture will be the refueling system in orbit. The Starship will need to transfer hundreds of tons of propellant to its tanks before launching towards the Moon or Mars. This means that several Starship flights dedicated to this single task will be required for each manned Starship. This increases the risk of failure and increases the bill.
It may be to solve this problem that Elon Musk has spoken on Twitter of another space vehicle even more disproportionate. It could reach 18 meters in diameter, twice the size of the Starship and its booster. It is hard to imagine the utility of such a monster except supplying in a single launch the Starship going towards the planet Mars.
The prototype of Starship has reached 150 meters altitude and the Starship Mk1 demonstrator will reach 20km of altitude
– News of September 1, 2019 –
The prototype of Starship, the Starhopper, flew 150 meters above sea level. It finally fulfilled his mission by proving that the Raptor engine is able to withstand take-off and landing phases. It can modulate its thrust and direct its nozzle to perform the kind of maneuvers that we have seen during Tuesday’s flight. This demonstrator will not go higher. It has been used to test the behavior and features of a low-speed, near-ground Raptor engine.
For the future, we must look at the Starship Mk1 which is still being assembled in South Texas. It will receive three Raptor engines, which should allow it to go much higher. It also means that it will be exposed to more constraints. SpaceX will begin to study the Starship’s aerodynamic behavior during supersonic phases or its resistance to heat.
In a recent tweet, Elon Musk said the Starship Mk1 will make an attempt to fly at 20 kilometers in October. If successful, an orbital flight attempt could follow fairly quickly. Despite the success of the Starhopper, the Raptor engine continues to be constantly changing. SpaceX is now at the 10th iteration of design. The company’s CEO believes that SpaceX still needs two or three months of work before it can develop an orbital capacity engine.
We also learned that the presentation of the Starship and Super Heavy system will take place on September 28th. This is an important date for SpaceX because on 28 September 2008 a Falcon 1 rocket reached the Earth’s orbit for the first time.
The takeoff of the prototype of Starship to 150 meters is postponed
– News of August 27, 2019 –
After a two-hour postponement, tank refilling and pre-firing countdown, the Starhopper’s recent takeoff test was stopped before being postponed. This delay will allow SpaceX to inspect the igniters of its Raptor engine. The Raptor engine uses a dual ignition system, which offers some reliability but complicates the development. The problem seems to be in the wiring, a problem that should be able to be resolved quickly. The next attempt will be tonight.
As a reminder, this will be the third flight of the prototype of the Starship, which is now equipped with the 6th iteration of the Raptor engine. The FFA gave permission for a flight up to 150 meters above sea level, with a maximum of 30 tonnes of propellant in the tanks. This should already offer us beautiful images and especially many data to the engineers of the company. In parallel with this test, the construction of the Starship Mk1 and Mk2 continues in Texas and Florida. We even saw parts arrive on site.
For more information, we will have to wait for Elon Musk’s presentation conference on the architecture of Starship and Super Heavy. In a tweet, the businessman said that this conference would take place when the Starship Mk1, assembled in Boca Chica, will have received its three Raptor engines, its fins and its landing gear. In the most optimistic hypothesis, this means that the conference will not take place until mid-September.
The Starship prototype takes off 20 meters
– News of August 20, 2019 –
The SpaceX Starhopper demonstrator made its first real atmospheric flight on July 25th. Its Raptor engine was fired for about twenty seconds to allow it to rise to 20 meters of altitude. SpaceX wants to make a more ambitious flight up to 200 meters in the coming days. After that the two prototypes of the Starship currently under construction should take over. Some photos from the Cocoa Florida site suggest that a Super Heavy booster is already being assembled.
NASA seems more and more seduced by the Starship. It announced that it may collaborate with SpaceX on orbit refueling, a key technology to enable lunar and Martian travel.
The Starship prototype catches fire during test
– News of July 21, 2019 –
On July 16, the Raptor engine was briefly fired under the Starhopper, the prototype of SpaceX’s Starship. The objective of this test was in the future to take off a few tens of meters this interplanetary spacecraft prototype. The static shot itself went pretty well but a few minutes later, while the Starhopper was stopped, it was suddenly wrapped by a fireball.
The flames lasted only a few seconds and the physical integrity of the Starship prototype does not seem to have been affected. This is most likely because of a leak. We will know more in the days to come. This may, however, add a bit of a delay to the tests of the prototype of Starship.
Starship’s engine explodes, production accelerates
– News of June 25, 2019 –
It appears that a Raptor engine exploded during a test following a failure of its turbine. We know that SpaceX modifies the tests of its Raptor engines permanently. The company expects to find a solution to this problem in just a few weeks. It means that we will have to wait a little before the prototype of the Starship takes off.
On Twitter, Elon Musk said the production of different versions of the Raptor engine is accelerating. SpaceX hopes to make two a day by the end of the year. Such a pace suggests that the company is already projecting well beyond the Starhopper. A large number of Raptor engines will be needed to equip both prototypes of orbital Starship currently under construction.
The booster called Super Heavy will also require dozens of Raptor engines. To learn more, we will have to wait for the detailed presentation of the Starship architecture that Elon Musk has promised to present this summer.
The Starship prototype takes shape, Elon Musk puts two SpaceX teams in competition
– News of June 4, 2019 –
Two months ago, a Raptor engine was briefly lit to lift the Starship prototype. This prototype is more like a big gas cylinder than an interplanetary spacecraft. It must be used to test the Starship’s propulsion into the atmosphere, up to a few kilometers above sea level. After the tests in early April, the only engine that was fired had been removed from the Starhopper by SpaceX teams. It seems, however, that these tests are about to resume.
A few days ago, a Raptor engine was installed under the Starhopper. This is a sign of a new test campaign that should make the Starship prototype fly without ties. We know that SpaceX now has three or four Raptor engines. It is not the one just installed that will be used to make the Starhopper take off. It should only be used for preliminary tests. In addition to this new engine, the entire Starhopper has been modified since the last test campaign. It now has a quick release cable system, attitude control and shock absorbers on its feet. It is therefore necessary to wait a week or two before finally seeing this strange machine take off. In recent months, SpaceX has accelerated the development of the Starship well beyond this simple atmospheric prototype.
The next phase must go through an orbital prototype, or rather two. In recent weeks, sheet metal plates have been assembled in Boca Chica (Texas) and Cape Canaveral (Florida). SpaceX has decided to put two of its teams in competition internally. They will test different ideas and concepts to try to assemble the best possible Starship. From the first welds, some differences appear. It’s not the same size of sheet metal that was chosen by both teams. Work on the external structure of these prototypes seems to advance very quickly. The model of Boca Chica has already received its nose, we hope that this time it is well attached.
In addition to this research and development, SpaceX is studying the choice of the launch site for its orbit prototypes of 9 meters in diameter. Kennedy Space Center launch complex 39A appears to be the company’s favorite. It is already the launch site for Falcon and Falcon Heavy rockets. In this case, it would be necessary to build a new launch tower and a landing area nearby. Indeed, it will be difficult to transport by road this huge spaceship. Landing closer to the launch site will allow faster reuse.
SpaceX has already been incredibly active on the Starship in 2019. The next few months are still full of surprises. Elon Musk is expected to reveal the latest developments in spacecraft design in the coming days or weeks.
NASA is not yet convinced by the Starship, tests continue
– News of May 7, 2019 –
NASA is not yet convinced by the Starship, the prototype interplanetary spaceship imagined by Elon Musk. Elon Musk revealed on Twitter that NASA is still waiting for progress before announcing possible support for the Starship. We guess that SpaceX will first have to succeed in sending astronauts into space with the Crew Dragon space capsule before hoping to get NASA support for the Starship.
In the meantime, the Raptor engine tests continue. The engine that propels the Starship was fired for 40 seconds during a test at the McGregor, Texas site. The Raptor engine seems now ready to take the Starhopper to a few tens of meters of altitude. We do not yet know the schedule for the rest of these tests.
The Starship could take NASA’s giant space telescope to space
– News of April 16, 2019 –
NASA trusts more and more SpaceX. The US space agency has just given SpaceX the launch of the DART mission expected in 2020 or 2021. Some people think that NASA could entrust SpaceX with other major missions, such as the launch of the LUVOIR space telescope ( Large UV / Optical / Infrared Surveyor), the successor to the James Webb Space Telescope. This launch could take place on the SpaceX’s Starship.
The Goddard Space Center tweeted an image that shows that the giant telescope could be integrated into the Starship. It will need a very large rocket to launch this telescope which mirror could reach 15 meters in diameter and the Starship seems made for this work. It is especially the first sign of interest of the American space agency for the Starship, a project which NASA had not so far wished to be associated. Perhaps the first tests of the Raptor engine and the construction of the prototypes are slowly convincing NASA.
The Starship prototype took off a few centimeters during tests
– News of April 9, 2019 –
The SpaceX’s Starship must allow to bring men beyond the low orbit. A prototype to test the behavior of the vehicle in the atmosphere was assembled in the southern United States. This prototype nicknamed the Starhopper is equipped for the moment with a single Raptor engine. It has just started a test campaign. The Starhopper’s engine was fired twice, on April 3rd and 5th. In both cases, the combustion lasted only a few seconds. It seems that it was enough to take off the prototype of a few centimeters.
SpaceX has not yet submitted a calendar for further tests. We know that ultimately, the company wants to make this Starship prototype fly up to 5 kilometers of altitude. So far, the new Raptor engine has never worked for more than a few seconds, either on a test bench or during tests on the prototype. Last week’s tests are still important milestones as this is the first time a rocket took off using a methane-burning engine.
All propellants are used for propulsion, which is not the case in traditional engines. They must indeed burn a small part of their propellant to drive their turbo-pump. The performance gain is actually quite low, a few percent. But every percent counts to reach Earth’s orbit.
There is still a lot of work to do before the Starhopper really takes off. It will probably be necessary to wait until it is equipped with three Raptor engines, which will give it a little more possibilities to modulate its thrust. We can already imagine the huge flames that will be produced when dozens of Raptor engines burn simultaneously on a Super Heavy booster.
The first test flight of the Starhopper is close and Elon Musk specifies the design of the Starship
– News of March 19, 2019 –
SpaceX has sent a note to residents of the area to report that the first trials of the Starhopper, the Starship test model, could take place this week. The development of SpaceX’s spacecraft continues at high pace.
Elon Musk has also sent several tweets that give us information on the architecture of the spacecraft and its development plan. The Starhopper as we can see it today is very close to its final design.
The company does not want to rebuild the conical section that had been shot down by strong winds a few weeks ago. The Starhopper should indeed not reach high speeds requiring an aerodynamic fuselage. The fuselage part that we can see under construction near the Starhopper is therefore intended for the orbital model of the spacecraft.
The Starship and Super Heavy will be built simultaneously in Boca Chica and Cape Canaveral. The first orbital model will be full size and should therefore have characteristics very close to the final Starship.
Elon Musk also talked about the heat shield system of his spaceship. He had talked about a transpiration cooling system, but it will not be the only cooling system used. The Starship will also be equipped with thermal protection tiles on its most exposed face during atmospheric reentry. These thermal tiles will be hexagonal to avoid offering gas acceleration channels between them.
The thermal tiles have already been successfully tested at temperatures simulating a return to orbital speed. The transpiration cooling system will be put where the thermal tiles will be the most likely to erode as well as at the hottest points of the least exposed face during atmospheric re-entry.
The transpiration cooling system consists of evaporating a liquid by micro perforations on the outer shell. This is a way to evacuate the excess heat that accompanies atmospheric friction. This should allow the Starship to be relaunched in space without maintenance, which is a necessary condition to hope one day to take off from planet Mars.
The first propulsive leaps of the Starship should take place soon
– News of March 12, 2019 –
SpaceX is rapidly advancing on its atmospheric Starship prototype. The future interplanetary spacecraft of the American company could start its propulsion tests fairly quickly. The first operational Raptor engine should be installed on the prototype as early as this week. The Starhopper will then begin a series of tests for loading and unloading propellants, controlling flight systems and static firing. If all goes well, it will quickly make small propulsive leaps.
For its first flight tests, the Starship will be suspended by cables. In the coming months, the Starhopper should have more and more Raptor engines and test them in different configurations. When SpaceX is confident enough, they will be able to get rid of the cables to make real propulsive leaps. A few months ago, Elon Musk had promised that the new architecture of the Starship and its booster Super Heavy will be revealed at that time.
The tests of the Raptor engines that will equip Starship continue
– News of March 5, 2019 –
After three weeks of intensive testing, the first prototype is no longer functional. This is normal because the goal was to push it beyond his limits. A second Raptor engine is now taking over. The pace of development and testing of the Raptor engine is incredibly aggressive, which gives hope that a first atmospheric bounce of the Star Hopper in 2019 is still possible.
SpaceX tests the Raptor engines that will equip the Starship and the Super Heavy booster
– News of February 5, 2019 –
On February 3, SpaceX tested the new version of the Raptor engine to propel the Starship’s atmospheric test model currently under construction in Texas, the Starhopper. The Raptor engine reached about 60% of its power, which provided a thrust of 116 tons. This first Raptor engine designed to fly is a simplified version of the final design. SpaceX wants to be operational as soon as possible.
Rather than developing two versions of the engine, a version optimized for atmospheric flight and an optimized version for space vacuum propulsion, SpaceX prefers to create a single engine halfway in terms of specifications. For now, the Starship test and its booster will be equipped with the same model of Raptor engine that will provide a thrust of about 200 tons.
Later in the development of the engine, SpaceX will optimize its design by developing a higher thrust version for the first stage and a high-impulse version specific to the Starship. In the meantime, we know that three of these first Raptor engines will equip the Starhopper. We imagine that static firing tests a little more advanced are planned.
The top of the Starhopper is still under repair. A dome that looks like the top of a tank is being installed on what’s left of the Starhopper. To optimize production lead times, engine tests and prototype construction both took place in Texas. We don’t know when the Starship test model will be launched, but preparations seem to be moving forward.
Starhopper, Starship’s test model, damaged due to high winds
– News of January 29, 2019 –
On January 23, the top of the Starhopper, the atmospheric test model of SpaceX’s future spacecraft, felt due to high winds in Texas. The piece is completely folded and now seems unusable. At least several weeks are added before the first atmospheric bounce of the demonstrator.
SpaceX can console itself by thinking that it is only stainless steel at $ 3 per kilogram and a few dozen hours of labor that will need to be planned. This incident should not weigh too heavily on the cash of the US company. It would have been more annoying if SpaceX had lost a carbon fiber piece.
Elon Musk was interviewed by Popular Mechanics magazine about the choice of materials. Stainless steel is the material chosen for the Starship for a cost reason, but not only. The selected alloy offers high resistance at very low temperatures and very high temperatures, which is ideal for a spacecraft that will house cryogenic propellants and make atmospheric entries at high speeds. This allows to build a slightly lighter thermal shield, or no themal shield at all.
The CEO of SpaceX is considering cooling by transpiration. The Starship would have a double wall stainless steel at its most exposed to friction. Water or even fuel could flow between these two walls. The outer wall would be traversed by micro-perforations allowing this liquid to evaporate and thus evacuate heat. This double wall would also strengthen the structural strength of the spaceship.
The Starship test model is assembled very fastly in Texas
– News of January 7, 2019 –
In Boca Chica, Texas, the Starship test model is moving at a rapid pace. This model of SpaceX’s future spacecraft will be used to perform a series of atmospheric hops to test the materials and technologies needed for this pharaonic project. Ten days ago, we saw on the internet two parts of the spacecraft being assembled. They have grown well since the last two weeks. The stainless steel structure begins to look like a real space rocket.
Elon Musk wants to go very fast. He hopes the first atmospheric hops of this Starship test model will take place in four weeks. This seems extremely optimistic. The design of the Raptor engines that will equip the Starship is being redone, and we have not yet seen a reservoir on the Boca Chica site. So there is a lot of work left.
2019 will be crucial for the development of SpaceX’s Starship and Super Heavy
– News of December 27, 2018 –
It has been several years since Elon Musk presented his vision of a gigantic rocket capable of taking men beyond the Earth’s low orbit. This two-part structure, a booster and a spaceship, must serve to fulfill the dream of the creator of SpaceX to go on the Moon and Mars. This structure has had several names, such as BFS and BFR. From now on, you have to call the ship “Starship” and the booster “Super Heavy”.
Until now, this giant launcher was still a concept. Several designs have been presented, and even some mission architectures. But apart from a few engine tests spread over several years, the Starship and its booster Super Heavy remained a concept in development. That could change in 2019. SpaceX is no longer the small start-up that wants to challenge the big ones. The American company has achieved its first bet, to make its rockets reusable and to become a major player in the industry of access to space. This performance requires us to bring some credit to the interplanetary dreams of its founder, especially as the concept of Starship begins to become concrete.
In recent days, photos from Boca Chica in Texas show two metal structures, a tower with feet and a large cone. These elements and the questions that they arouse led Elon Musk to express himself. As usual, the leader of SpaceX made his statements on Twitter. We learned that the tower and the cone that were photographed are elements of Starship’s atmospheric test model.
First, SpaceX wants to test the materials and technologies of its interplanetary spacecraft using this model. It will be smaller but just as wide as the final design. Its role will be to make a series of atmospheric bounces at low altitude, up to 500 meters high, then up to 5 kilometers high in a second time. This model will have exactly the same function that the Grasshopper had for the development of the Falcon 9. Elon Musk hopes that this test model will be able to realize its first atmospheric bounces in March or April 2019. Other executives of the company have referred to the end of 2019.
Despite these advances in the construction of the test model, the final design of the Starship is not over. Elon Musk had revealed first that SpaceX would build its spacecraft with composite materials based on carbon fiber. Their lightness and rigidity would have guaranteed excellent performance for the spacecraft and its booster. SpaceX seems to finally opt for stainless steel. The selected alloy would offer a better resistance-to-weight ratio at cryogenic temperature as well as in the very high temperatures encountered during an atmospheric reentry. This would reduce the thermal protection needed for the spacecraft. The surface of the vehicle would not be painted, it would be polished like a mirror in order to limit as much as possible the heat related to the sunlight.
The Raptor engine that will power the Starship and the Super Heavy will also undergo significant changes. A superalloy has been developed specifically for the engine. It is designed to withstand immense pressures. SpaceX has its own smelter, which will allow it to quickly modify the Raptor engine based on the results of the first tests on the atmospheric test model currently under construction in Texas.
This desire to test the main components of Starship as quickly as possible seems to be at the heart of SpaceX’s approach. The Falcon 9 was launched on the launcher market as soon as possible. The American company had then improved as and when its flights. In 2019, SpaceX will launch its first manned flights thanks to the Crew Dragon. Feedback from the Crew Dragon will also be used for the Starship project.
SpaceX has already abandoned the mini BFS
– News of November 20, 2018 –
Elon Musk went back on his statements about the mini BFS used as the second stage of a Falcon 9. Instead, SpaceX wants to accelerate the full-size tests with a first model of BFS. The construction seems to advance under the big white tent of the port of Los Angeles. We can even see a huge black dome, which is most likely part of the monstrous tanks 9 meters in diameter that will equip the spacecraft.
If a first BFS may already be under construction, its design is not fixed. The CEO of SpaceX has indicated that a major and counter-intuitive redesign is in progress. The BFR has not finished evolving. The motorisation and the general dimensions of the BFR will however probably remain the same. Elon Musk seems to want to name the different parts of the BFR. The spacecraft that forms the second stage would have the name “Starship”, while the first stage would become “Super Heavy”.
SpaceX will build a mini BFS to do tests
– News of November 13, 2018 –
SpaceX continues the development of its interplanetary spaceship, the BFR (Big Falcon Rocket). Such an ambitious project will involve many new technologies. SpaceX is already well-prepared with the propulsive braking and the propulsive landing of its Falcon 9 rocket. But on the BFR project, the whole launcher has to be recovered, that is to say the first stage and the second stage. But getting back a second stage a a rocket is a lot harder than getting back a first stage. It is necessary to perform an atmospheric reentry at orbital speed, then cancel all this speed before reaching the ground, which corresponds to braking from 28,000 km / h to 0 km / h in just a few minutes.
As the BFR will be a manned space vehicle, additional constraints must be taken into account. The deceleration should not be too brutal. The occupants of the Apollo capsules could collect up to 6G or 7G during their atmospheric reentry. The first passengers of the BFR will not be experienced fighter pilots, they will apparently be artists. It is impossible to subject them to this.
To address these specific issues, SpaceX has designed a second stage between a rocket and a shuttle, called BFS (Big Falcon Spaceship). The BFS must enter the atmosphere by its belly, which allows to significantly increase the atmospheric friction and thus quickly reduce the speed of the spacecraft. Once its speed is low enough, the BFS must switch to allow its engines to go into action. The end of flight resumes the scenario of a first stage of the Falcon 9, with a retropropulsive landing. SpaceX knows how to make retropropulsive landings, but has not yet experienced atmospheric reentry of a spaceship by its belly. The BFS is an enormous spacecraft 9 meters in diameter and 55 meters long. The SpaceX engineers would therefore prefer to test their ideas with a slightly smaller model to begin with.
Last week, we learned on Twitter that the company of Elon Musk will modify a second stage of Falcon 9 to create a kind of mini BFS. The aim of SpaceX is to acquire the necessary skills for the atmospheric reentry of the Big Falcon Spaceship. SpaceX needs data on the behavior of heat shields and very high speed spacecraft control systems. The mini BFS is not expected to return to land thanks to its rocket engines. This phase of flight will be directly tested by a full size BFS, which is currently under construction and could be tested next year in Boca Chica, Texas. The BFS test will perform a series of hops higher and higher, at faster and faster speeds. Elon Musk did not release a date for testing this mini-BFS. There is still a lot of work before seeing the BFR in action. The Falcon 9 rocket will therefore remain an asset for SpaceX’s business model for at least a few more years.
SpaceX unveils the new design of the BFR and schedule an overfly of the Moon in 2023
– News of September 18, 2018 –
Two years ago, SpaceX presented the BFR project, a space rocket and spacecraft capable of taking humans to the planet Mars and beyond. Since then, it has become a habit every year. Every September, SpaceX presents project news. The last of these conferences took place yesterday in the United States of America. This was an opportunity for Elon Musk to detail the new design choices of the Big Falcon Rocket and to talk about its first manned mission, a touristic overfly around the Moon.
The BFR has again changed a lot compared to last year. The set consisting of the booster and the spaceship is longer. At launch, the space rocket should have a height of 118 meters, which is 12 meters more than previously announced. The Big Falcon Rocket will be 48 meters long, and the BFS spacecraft will be 55 meters long. There is no change in diameter of the Big Falcon Spaceship, which is still of 9 meters. This should offer the BFS a living volume close to 1100 cubic meters. SpaceX has not yet developed the interior of the spacecraft, which will in any case be adapted to the missions with more or less complete systems for humans. The Big Falcon Spaceship’s propulsion will consist of seven Raptor engines. The spaceship should be able to survive without problem with the loss of two or three of them.
SpaceX wants to optimize the spacecraft development time using the same version of the Raptor engine everywhere. This results in a small loss of performance but it is much simpler. Around the seven engines, there are twelve cargo containers arranged in a circle. It is convenient to unload and it allows to lower the center of gravity of the spaceship. Containers may eventually be replaced by Raptor engines, which would greatly improve the performance of the spaceship to the planet Mars. Even without this improvement, the space rocket should be able to carry a hundred tons of payload to the surface of the red planet.
The silhouette of the BFS is transformed with the addition of three large wings at the rear, and two retractable fins at the front. These two fins and these rear wings will be mobile. They will guide the trajectory of the rocket during its atmospheric reentry. The feet, which will be used for the landing of the spacecraft, are embedded at the end of the rear wings. The silhouette of the Big Falcon Spaceship strongly recalls the rocket of Tintin. The BFR and the BFS still require a long development. Elon Musk hopes to make small atmospheric jumps next year and a first orbital flight within two or three years. But he admits that this is an optimistic calendar. If everything goes smoothly, it will probably take some extra time.
The cost of developing the BFR and BFS is estimated at about $ 5 billion. Part of this amount was financed by Japanese billionaire Yusaku Maezawa. In return, he would become the first passenger of the Big Falcon Rocket for a mission to fly over the Moon that could take place in 2023. He would invite artists to share the adventure with him. Elon musk reminded that whatever the precautions taken, flying BFR will still be dangerous. He made it clear that there could be deaths in the attempts to colonize the Moon and Mars, which may be difficult to accept for the general public. In the meantime, the BFS should quickly start its atmospheric tests. A prototype is currently under construction under a large white tent in the port of Los Angeles. In the presentation, we could see a first section of the fuselage that gives an idea of the scale of the spacecraft. Elon Musk is optimistic about the chances of the BFR project to succeed.
SpaceX will focus on the development of the BFR
– News of March 13, 2018 –
Last week, SpaceX launched its 50th Falcon 9 rocket. At this rate, the 100th will arrive very quickly. Between the end of March and the end of April, SpaceX will launch six Falcon 9 rockets in one month, including three launches in a single week. But SpaceX looks beyond this launcher : Elon Musk said last September that once the Falcon Heavy was operational, SpaceX’s development efforts would focus on the Big Falcon Rocket rocket (BFR) and the Big Falcon Spaceship (BFS).
In an interview on March 11, the founder of SpaceX recalled his ambition. He wants to start the BFR tests next year. The rocket must use two main elements : a fully reusable booster burning methane and liquid oxygen, and the second floor a spacecraft with interplanetary capacity, livable and also fully reusable, called BFS. The set should allow to make the inhabited trip to Mars and other celestial bodies of the solar system.
In his statements, Elon Musk said the plans for the booster and the spaceship have undergone some changes since their presentation last September. So we can hope for a new presentation at the upcoming International Astronautical Congress. It is apparently the BFS spacecraft that will be tested first. According to Elon Musk, the construction of the first prototype has already started and the company hopes to conduct the first tests during the first six months of 2019. These tests will be of the same type as those that had been done with the Grasshopper : jumps over quite low distances and altitudes. As they unfold, the tests will take the spacecraft to an altitude of several kilometers.
There will be many things to test on the BFR. We know that SpaceX has been working for nearly ten years on the Raptor engine that will equip the BFR. The spaceship of the BFR must also be able to perform atmospheric re-entry in the manner of a sail. Elon Musk has precisely specified that the thermal protections would be part of the elements tested.
Elon Musk gives details on the BFR on Reddit
– News of October 17, 2017 –
Elon Musk, CEO of SpaceX, took advantage of a Reddit Q & A session to tell about the Big Falcon Rocket (BFR), also known as Big Fucking Rocket. The subject has more than 12000 messages.
The leader of SpaceX began by discussing the problem of radiation. SpaceX considers that radiation levels do not require special protections for the duration of the trip. The spaceships of the company will however be equipped with a shelter in case of solar storms. SpaceX will not take care of the Martian colonization itself : the purpose of the company is to offer a means of transport and basic infrastructure on Mars. Other companies and organizations will be able to exploit this opportunity. Elon Musk compares the BFR to the arrival of the railway which was accompanied by the development of adjacent cities.
SpaceX is trying to lighten the BFR. For example, the thermal protection tiles will be mounted directly on the tanks, without intermediate structure. The spaceship of the firm is named the Big Falcon Spaceship (BFS). The small fins are not used to provide lift but a means of control during atmospheric reentry without payload. The BFS should be able to go into Earth orbit by its own means. The BFR is just there to allow it to embark a maximum of payloads.
Thanks to the reduced Martian gravity, the BFS will do all the work from the surface of the red planet. The trips will be made with the nose of the spaceship pointed at the sun, in order to prevent the fuel in the tanks from boiling. The Raptor, the rocket engine that will equip BFR, will be partially printed in 3D. We also learn that a new metal alloy has been specially developed for the oxygen pump. The goal is to achieve a level of reliability similar to what is done for civil aviation engines. However, we learn that the power of the Raptor has been revised downward from 300 tons of thrust to 170 tons, which explains the reduced performance of the BFR compared to what was announced previously. Nevertheless, this drop in power should significantly increase the reliability and security of the BFS.
A third Raptor equipped with an atmospheric nozzle was added to the design that was presented in September, again for reliability concerns. Elon Musk said that for reasons of efficiency, the first tanker spacecraft will be BFS and ultimately the company will design a dedicated spacecraft. Regarding the use of the BFR for intercontinental flights on Earth, the company will start by experimenting on small leaps of a few hundred kilometers. This will test the technique without heat shield.
Some users of Reddit have revealed interesting points : for example, the fact that SpaceX wants to build its rocket and operate links between the Earth and Mars, while US antitrust laws could put everything in question. By 1934, Boeing had had to abandon its airline business to focus solely on aircraft manufacturing. Indeed, the US justice does not allow a manufacturer of aircraft to operate commercial links and vice versa, and it is conceivable that the competitors of SpaceX will use this law.
Elon Musk announces first launch of BFR to Mars in 2022
– News of October 3, 2017 –
Last week, the 68th International Astronautical Congress was held in Adelaide, Australia. Elon musk, the CEO of SpaceX, shared his vision for the near and far future of his company. To develop its heavy launcher BFR, the American company is facing a major difficulty, financing. Developing the most powerful launcher in the history of humanity would require injecting a few billion dollars. The company is currently spending a lot of money developing Falcon 9 and Falcon Heavy rockets, as well as its Dragon space capsule. With the BFR, the rocket that will be used for the colonization of Mars, SpaceX wants to make all its other products obsolete. In other words, SpaceX ultimately wants to offer only one gigantic rocket and able to fulfill all missions. It must be fully reusable and require little maintenance. Ideally, the cost of a launch would be limited to the cost of propellants. Once the Falcon Heavy operational, SpaceX would switch all its research and development capabilities on the BFR and the spacecraft that will accompany it.
The work has actually already started. We learned that the rocket’s liquid oxygen tank has been tested under real-world conditions, and the Raptor engine has already run over 1200 seconds in 42 tests. The BFR would therefore be a monster capable of putting into a low orbit a payload of 150 tons in a fully reusable configuration. According to Elon Musk, this gigantism will also allow the BFR to become the cheapest launcher on the market. If the whole rocket is reusable, it is indeed possible. The BFR is 106 meters high and has a diameter of 9 meters. Its first stage is equipped with 31 Raptor engines providing a takeoff thrust of 5400 tons, which is more than enough to lift the 4400 tons of the space rocket. The spaceship that was presented with this rocket could have several applications. The main application would of course be the trip to Mars. It would then be used in two versions, an unmanned cargo version and a version capable of accommodating a hundred passengers. It will measure 48 meters long and will weigh 85 tons. In its inhabited version, it will have a pressurized volume of 825 cubic meters. It’s more than aboard an A380. The travelers will share 40 cabins, in addition to common rooms and a shelter against solar windes. The spacecraft will be able to store 1100 tons of oxygen and liquid methane, which is enough to make the trip to Mars from Earth’s orbit. However, it will be necessary to produce fuel on site for the return trip.
Elon Musk briefly touched on the issue of fuel production. This will require the installation of a gigantic surface of solar panels. Methane and liquid oxygen will be produced from the Martian atmosphere and Martian water. The spacecraft will also be equipped with small wings capable of providing lift and maneuverability in atmospheric environments. On the other hand, it would offer the possibility of traveling back and forth to the lunar surface on its only fuel reserves, provided that it is refueled on an elliptical transfer orbit. The Martian mission architecture will rely on the spacecraft that will be placed in low Earth orbit. It will then refuel propellant with the help of several tankers. The trip to Mars will take a few months. The vast majority of braking will be aerodynamic, with the ignition of one or two Raptor engines of the spacecraft during the final phase. For the return, thanks to the low Martian gravity, the spacecraft will be able to reach the Earth’s surface from the Martian surface without rocket, and with only one full of propellant.
SpaceX hopes to conduct a first mission to Mars with the BFR and its spacecraft in 2022. This first space mission would be fully automated and would use at least two cargo spaceships to place the first infrastructure on the Martian soil and to locate the resources needed for the Martian base. In 2024, four spaceships would depart to Mars with the first human explorers on board. Their main mission would be to set up the methane and oxygen production plants needed for their return. It would also be an opportunity to establish a permanent base on the surface of the red planet. In the longer term, Elon Musk wants to colonize Mars so that humanity becomes a multi-planet species.
Image by spacex.com