The first flight lasted just under four minutes. With 30 of its 33 engines ignited, the first of SpaceX’s Super Heavy boosters blasted off from the Boca Chica launch pad on the Texas coast at 1:33 p.m. GMT. One minute later, it reached Max Q, the point of maximum dynamic pressure on the vehicle as a consequence of the thrust of the engines and the resistance of the atmosphere. Within two minutes, the rocket had reached an altitude of 20 kilometers and was traveling at 1,600 km/h, although at least two other engines had also died.
By the third minute, it became clear that something was wrong. The other engines had not shut down at the expected time; the rocket seemed to change orientation in a strange way; the separation of the second stage of the Super Heavy (a prototype of the Starship spacecraft) was not proceeding as planned. As the footage showed the erratic motion of the rocket, John Insprucker, a SpaceX engineer commenting on the company’s live broadcast, uttered a technical understatement for posterity: “Clearly…this doesn’t appear to be a nominal situation.” . A few seconds later, with the rocket already clearly out of control, the “flight termination system” did what it had to do and the device exploded over the Gulf of Mexico.
It was not immediately clear, at least to outside observers, what went wrong. Taking off with fewer engines and losing others during the climb may have been crucial, but there are other possibilities. The good news is that SpaceX says it’s building Super Heavys and Starships apace; Therefore, in principle, it will be possible to repeat the test within a reasonable time, once the nature of the problem has been clarified and a solution found. The bad news is that the structure that supports the Super Heavy when it is launched appears to have sustained damage that will require significant redesign rather than simple repair. This could lead to significant delays.
The company and its many supporters will emphasize the positive. The rocket rose and passed Max Q, two things he hadn’t done before. The goal of flight testing is to find problems in processes that cannot be tested on the ground. In that sense, the test was a success. And, although this vision smacks of somewhat excessive optimism, deep down it is accurate. Had it gone as planned, the flight would have been a formidable success. Going part of the way and already being prepared to keep trying is, without a doubt, achievement enough. The possibility of the Starship system representing a huge leap forward in space travel remains something to be taken very seriously.
The Super Heavy is the most powerful rocket ever built; in principle, its liftoff thrust is more than double that of the Saturn V rockets that carried men to the Moon; although with three engines out she might not have been able to achieve that goal. The Starship, which is to act as the second stage, will be (when it succeeds) the largest spacecraft put into orbit with a single launch since the days of the Space Shuttle.
If SpaceX corrects the problems that led to the destruction of the rocket and those that the test program will surely bring to light, the Starship system will not only be able to launch larger payloads into orbit than any other competitor, but It will be able to do so at a cost per ton much lower than what has been seen up to now in the sector. This low cost is one of the advantages offered by a system with only two parts, both totally reusable. Another is that a system capable of taking off, landing and taking off again in a short time opens up a whole new range of possibilities for flights beyond Earth orbit. If it meets the expectations of Elon Musk, the head of SpaceX, the Starship system will be able to take human crews to the surface of the Moon and even to Mars.
However, there are still many capabilities to be added before all of that becomes a reality. Even if it had been successful, this first test would only have been the beginning of a development process that will require much more effort and investment.
The flight plan for this first mission was very similar to the plans that have become routine for SpaceX’s Falcon 9, the rockets with which the company has managed to dominate the satellite launch business. The first stage booster was to fly to the edge of space and then return in a controlled manner to the surface while the second stage was launched into orbit.
However, there are two crucial differences. When a Falcon 9 rocket returns to Earth, it unfolds its legs and lands. Had they managed to execute the necessary maneuvers to get that far, the Super Heavy would have plunged directly into the Gulf of Mexico.
The main reason for that difference is that although the Super Heavy is intended, like the Falcon 9 first stage boosters, to be fully reusable, unlike a Falcon 9 booster, it has no legs to land on. Fold-out legs sturdy enough to support it would add unacceptable weight. So the Super Heavys will descend on the platforms from which they are launched and there they will be caught still in the air by huge mechanical arms.
The launch pad tower used for Thursday’s test flight, dubbed Mechazilla by its stalwarts, is equipped with those arms. They were used a couple of days before the launch to lift the Starship and place it on top of the Super Heavy that was already on the Boca Chica pad. SpaceX understandably wants to make sure it knows how to accurately return large boosters to Earth before trying to catch them; and not the least reason for this is the fact that test rockets are expendable in a way that infrastructure-heavy launch pads are not. The only result of the first test with which the company would have had to consider the attempt a true failure would have been an explosion that destroyed the launch tower. False “landings†in the sea are the obvious way to build confidence in the booster before attempting to catch it in the air.
The second difference between the plans for that test flight and a normal Falcon 9 flight is that when a Falcon 9 puts something into orbit, it stays there until the operator decides to bring it back. The Starship that overlapped the Super Heavy and shared its fate would have remained in orbit for just over an hour if everything worked perfectly. The engines would have put it on a trajectory to re-enter the atmosphere over the Pacific, and it would have circled Earth completely. Her final destination was slated to be a stretch of sea about 100 kilometers off the northwest coast of Kauai, the northernmost major island in the Hawaiian chain.
Later, the ships will go into orbit, deploy satellites, re-enter the atmosphere and land thanks to the embrace of Mechazilla. However, they first have to prove that they are capable of surviving reentry.
Neither the Falcon 9 nor the Super Heavy rockets enter the atmosphere with a speed that requires a heat shield. The Starship, yes, and for this reason the parts most exposed to heat are covered with hexagonal plates of thermal protection. Now, we won’t know to what extent they work until the company manages, in future tests, to bring back an intact Starship. The system is considerably more ambitious than in the case of the heat shields used on the Dragon spacecraft, which is much smaller and is used to fly crews to the International Space Station and back. This is likely the aspect of the Starship system that is furthest from the capabilities demonstrated by SpaceX to date.
The prize for success will be a launch system with unparalleled capabilities. The company claims that a Starship launched by a Super Heavy will be capable of putting between 100 and 150 tons of cargo into orbit. This figure far exceeds the capacity of what is today the most powerful commercial launcher, SpaceX’s Falcon Heavy, basically made up of three Falcon 9s joined together and capable of lifting up to 64 tons. The load that the space shuttle could lift was only 24 tons.
That number is also more than any of the three big new launchers other companies are working on: the Ariane 6 developed by ArianeGroup, a joint venture between Airbus and French defense contractor Safran; the Vulcan Centaur, a project led by ULA, a joint venture between Lockheed Martin and Boeing; and New Glenn being developed by Blue Origin, a company founded by Amazon CEO Jeff Bezos (see diagram). A working Starship system will not only outsize them all, but to the extent that it will be fully reusable, it will also be much cheaper. The Ariane 6 and the Vulcan Centaur are single use. ULA’s intention is to recover the engines of its Vulcan first stage. The New Glenn is designed to have a fully reusable first stage, like the Falcon 9.
However, the Starship system is intended to do more than just carry payloads into Earth orbit. NASA has chosen a version of the Starship as the ship with which to bring humans back to the surface of the Moon. In Musk’s plans, it has always been the vehicle that will take them to Mars. For any of those things to happen, another new technology is necessary: ​​in-orbit refueling.
A rocket needs fuel and oxidizer to work. In the case of the Raptor engines that power both the Super Heavy and the Starship, the fuel is liquid methane, and the oxidizer is liquid oxygen. By the time it reaches orbit, the Starship will have consumed most of both. Therefore, if you want to go further, you have to refuel. To achieve this, SpaceX plans to build a fleet of Starships configured as tankers.
The plan for NASA’s first Artemis moon landing, scheduled for the second half of this decade, highlights the level of effort required. The first step in the plan is to put a Starship configured as a resupply station into orbit around Earth. A series of tanker missions will then fill it with liquid oxygen and methane. SpaceX’s agreement with NASA indicates that 14 missions will be needed, but Musk has stated that it may be far fewer. Once the resupply station is full, a special version of the Starship will be sent out to dock with it, refuel, and head for near orbit of the Moon. There it will embark astronauts who have reached the same orbit by other means and transport them to the surface. Once its mission is complete, it will take them back into orbit.
For this to work, two things are necessary. One is the technology needed to dock two spacecraft, transfer large amounts of very cold liquid from one to the other, and then undock. Automatic docking is a fairly routine affair by now; the transfer of large amounts of liquids from one spacecraft to another, no.
The second is for heavy pitching to become a regular experience. If many tankers have to be launched for each manned mission, it is necessary to be able to establish a rapid rotation of the tankers and move rockets to launch facilities much faster than has been achieved to date. Currently, SpaceX launches its Falcons 9 a little more than once a week, a rate higher than that achieved by any other company or country. However, to take significant numbers of crewed Starships to destinations beyond Earth orbit, the company will need to be able to launch daily, and possibly even more frequently.
Before Musk’s dream of interplanetary flights materializes, the Starship system still has a long way to go. Its Super Heavys have to be able to return to the landing site with unerring precision, the Mechazilla system has to work its magic on a routine basis, the Starships have to master reentry, and the entire ensemble be able to operate at a rate that the sector had never before imagined, much less tried. It is tempting to consider that building the most powerful rocket in history is actually the easy part of the whole undertaking.
However, it has not been easy, and it has already been done. And SpaceX’s track record of innovation is remarkable. There are many obstacles that lie ahead, although it is not difficult to imagine that they will also be overcome.
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Translation: Juan Gabriel López Guix
