On February 9, 2022, the National Academy of Engineering released the list of additional academicians for 2021, and SpaceX founder Elon Musk was successfully elected. The current world's richest man has successfully achieved "fame and fortune".
The scene of the "rough hardcore" press conference | Screenshot of the SpaceX conference video
Two days later, SpaceX held another press conference, and the new academician highlighted the latest progress of the strongest rocket starship in human history ( Starship ) .
The venue of the conference was the starship test base in Texas, USA, and even all the audience gathered around a simple open-air podium, projection panels and two rocket engines, which was really a very hardcore industrial style conference.
So, what did Academician Musk say?
The Raptor II engine appears
SpaceX's fame stunt is the low-cost, reusable, and highly reliable Falcon 9 series rockets. The root cause of this is its Merlin series of engines, especially the mature 1D version.
Multiple repetitive starts, variable thrust adjustment, ultra-high thrust-to-weight ratio, multi-engine parallel work and other characteristics make the Falcon 9 and Falcon Heavy series use this production engine, which greatly reduces the cost of the rocket.
The Falcon Heavy rocket's 27 Merlin engines | SpaceX
In the development of starships, the engine is still the most core technological breakthrough point. To this end, SpaceX has spent a lot of effort to develop a new generation of Raptor engines.
Raptor engines use a full-flow staged combustion cycle, with greater engine chamber pressure, stronger specific impulse, longer life, and greater thrust. It uses a lower cost liquid methane propellant, no carbon coking problem caused by liquid oxygen kerosene, lower cost and stronger reusability.
In the previous starship test, the Raptor generation engine performed well, with a single engine of 185 tons of thrust twice that of the previous Merlin 1D, witnessing the successful in-situ recovery test of the starship.
The comparison of the two versions of the Raptor engine shows that the second generation is more concise and has a larger thrust | SpaceX
At this press conference, SpaceX officially announced the research and development progress of the second generation of Raptor.
In the test, its thrust has been increased to a staggering 230 tons, and the overall structure has been greatly optimized, more compact and efficient, and the cost will be reduced to about half of the original version. In future research and development, it is expected that its thrust will further increase.
The superweight thruster B4, equipped with 29 Raptor rocket engines, will be equipped with 33 Raptor II engines | in the future as the first stage rocket of the Starship spacecraft BOCA'S BRAIN
SpaceX is already producing the engine at its new site, and future production efficiency is expected to be one per day. This is a big breakthrough. Achieving mass production is fundamental to making expensive aerospace research and development commercially profitable.
In addition, for the critical emergency escape capability of manned spacecraft, Raptor also offers a solution: the future manned starship spacecraft will be equipped with 9 Raptor engines, with a thrust-to-weight ratio greater than 1, enough to allow the spacecraft to escape safely in unexpected situations.
The first-generation (right) and second-generation Raptor engines at the press conference | Everyday Astronaut
If a worker desires to do a good thing, he must first use it. It can be said that the Raptor engine is the core cornerstone of the starship's success.
A mysterious power from the East - "chopsticks"
The rocket stage (booster) of the Falcon series rockets, as the only reusable rocket in service, can be recovered by using a ground-based fixed-point platform and a maritime-based fixed-point platform. Since the first successful recovery in December 2015, the recycling technology has become more and more mature, with more than 100 successful recoveries and 4 boosters breaking through 10 reuses, and this data is still increasing. Correspondingly, the recycling accuracy is also significantly improved.
So the starship, which uses a stronger propulsion system, simply plans to adopt a bolder recovery plan: catching the rocket that lands in the air through a huge robotic arm, and Musk himself calls this huge steel structure "Chopsticks" on social media.
The orbital launch tower is sandwiched by the starship spacecraft on the upper side, which is the "chopsticks" | SpaceX
However, there is still a certain difference between its working principle and chopsticks. After all, directly using such a huge steel structure to clamp the "thin skin and big stuffing" rocket in flight like a sandwich is really full of risks.
Its actual role is more like a giant crane, the reusable rocket flies back and gradually slows down the hover, and the tower structure is combined with the end of the rocket grid rudder to lock, thus lifting the huge rocket.
Recycling simulation animation is very sci-fi | SpaceX
The benefits of this design are obvious: the rocket does not need to design a huge and heavy landing leg, the overall transportation efficiency of the rocket is more efficient; the rocket is directly recovered to the launch tower, without going through the process of transfer, maintenance and reassembly, and the reuse cycle can be greatly shortened.
However, the disadvantages are also obvious, in case of any accident in the recovery process, the entire launch tower is afraid that it will be blown up.
Before the press conference, the "chopsticks" hoisted the starship spacecraft and completed the assembly with the overweight thruster, which was also a small test of | NASA Spaceflight
Arguably, this is a highly innovative "imaginative" recycling strategy. We look forward to SpaceX, which "continues to turn bold ideas into reality," to continue to surprise us.
A new generation of insulation tiles
The starship's goal is full arrow recovery, which means that the spacecraft itself that has flown out of the atmosphere and has entered orbit must also re-enter the atmosphere and fly back to the surface in its entirety, which is far more difficult than the existing recovery rocket stage.
After all, the rocket stage is slower and at a lower altitude, and the recovery process does not have to undergo intense air friction and heat generation. Flying back from outside the atmosphere at orbital speed is a different story, and the violent air shock is the nightmare of all spacecraft.
The space shuttle's thermal insulation tiles are one of the reasons why the space shuttle is expensive to maintain| NASA
The most successful strategy before was the equally reusable Space Shuttle, which at its core consisted of insulation tiles/blankets all over the bottom and key areas. The low weight and small size can isolate the high temperatures of thousands of degrees Celsius, which also leads to the extremely high price of this small tile and the soaring cost of maintenance and replacement.
Because of this, thermal insulation tiles are also the core technology in the development of starships. Over the past few years, SpaceX has made a series of breakthroughs in this area of research and development, and NASA and the US Air Force have also given research and development contract support.
The thermal insulation tiles used on the Starship spacecraft are more uniform in shape and convenient for mass production and maintenance, thereby reducing costs to | SpaceX
For the foreseeable future, these insulation tiles will not only be used by SpaceX itself, but will also be applied to other spacecraft in the United States.
When to enter the orbit
What is worth looking forward to at the moment is the time of the starship's first flight.
However, this is not the decision on spaceX's development schedule, and it will need to wait for a comprehensive environmental impact assessment by the Federal Aviation Administration (FAA). After all, the first flight of this nearly 5,000-ton behemoth is not a small event, and it even far exceeds the once 3,000-ton Saturn V lunar rocket.
Judging from the information revealed at the press conference, if it goes well, it is possible to be approved in March this year, paving the way for the first flight test of the orbit this year. In the future, there will be a launch site at the Kennedy Space Center, and even a sea launch site.
Starship full arrow firing simulation animation | SpaceX
With the above as a basis, it is not surprising that a series of "eye-catching" big news presented at this conference, such as:
The overall cost of the starship is even significantly lower than that of the Falcon 9 rocket, with a single launch cost of about $10 million;
The overweight booster can be successfully recovered a few minutes after launch and launched again after 1 hour;
In the future, it will be possible to produce a set of starships and superweight boosters in 3 days, and launch 3 starships in 1 day.
At present, these visions are not "horse bragging". The starship has been awarded NASA's manned lunar landing contract, which is an official affirmation. Japanese billionaire Yusaku Maezawa has already photographed the starship's first trip to the moon, and he has just proved his determination to ride on the starship with a trip to the International Space Station.
Going to Mars is SpaceX's established plan and has not wavered. In the press conference, Mars city, Mars flight, Mars development, is what everyone expects.
The starship future demonstration video played at the press conference | SpaceX
In addition, the starship with super passenger and cargo capabilities will itself become an efficient intercontinental transportation solution on Earth after achieving high-frequency launches and simple recovery methods.
Perhaps, in the future, starships will appear frequently in our skies. Some of them are traveling to another continent, and some are flying to another planet.