In December 2020, Astra launched Rocket 3.2 to space. The successor, Rocket 3.3, will make Astra’s first flight with a payload on board as early as this summer. And by the end of the year, the Rocket 3 series is planned to launch on a monthly basis.
In 2022, Astra is planning to debut Rocket 4.0 in order to launch missions weekly. CEO Chris Kemp spoke about these steps and the ones that will follow, including daily launches from around the world, during a recent episode of NASASpaceflight Live.
Early Astra rockets
In July 2018, Astra launched their first rocket, Rocket 1.0, on a suborbital test flight from the Pacific Spaceport Complex in Kodiak, Alaska, the same site that would host the entirety of Astra’s early test flight program.
“We flew the first rocket with a suborbital license just about a year after we started the business,” told Kemp. “And these iterations were never intended to make it to orbit. In fact, they couldn’t make it to orbit. The upper stage of that first rocket was a hunk of metal. And we accepted each of these steps because we would learn a lot about, for example in that case, the first stage. And with each of these steps, the team got just a tremendous amount of data.”
This iterative approach to research and development was integral to Astra’s plan to quickly achieve an orbital launch capability.
“You’re seeing this same approach now being applied with the Starship program. This isn’t how SpaceX did it the first time, but it is definitely the best way to do it. And we applaud how they’re iterating and how they’re making these generations of spacecraft faster and better. And this is exactly what we’re doing.”
Astra launched Rocket 2.0, another suborbital test flight, just four months later in November 2018. This was the final flight before the debut of the currently active Rocket 3 series, which incorporated several upgrades and changes from Rockets 1.0 and 2.0.
“The first rocket we did, 1.0, the nosecone cost almost a quarter of a million dollars because it was made out of carbon fiber. Much like the Rocket Lab rockets. We actually want the entire rocket to cost less than that in the end. So you can’t make the nosecone cost a quarter of a million dollars or even anywhere near that and get to the ultimate price target.”
“With the Rocket 2 series and 3 series, there were two different generations of the nosecones. And if you study the nosecone carefully, you’ll see the shape changes a little bit. And the price is now down around $25,000. So we’ve brought an order of magnitude cost out by using a really innovative aluminum and internal structure made out of aluminum tubes.”
In addition to fairing upgrades, the rockets also got bigger. “Between Rocket 1.0 and the Rocket 3 series, we got feedback from the market that we needed to put more payload in space. And with constellations like Kuiper, with the Starlink constellation being deployed, with OneWeb and several other constellations, we really wanted to address that entire market. And so we realized the rocket needed to be a bit bigger to put these communications satellites up. And so we increased the diameter of the rocket from 38 to 52 inches.”
Rocket 3 series
Rocket 3.0 was set to make a launch attempt with customer payloads on board as part of the DARPA (Defense Advanced Research Projects Agency) launch challenge, which sought a launch provider to conduct two orbital launches from different launch sites within just days of each other. On the final day of the launch window, Astra reached the terminal countdown, but a sensor issue caused an abort, and the DARPA launch challenge prize went unclaimed.
“In the actual DARPA Challenge, we got to T-52 seconds. We were in terminal count. And what actually prevented us from launching, I was very proud of the team, because it was sensor input that we got. And it was probably as one of the tanks was pressurizing.”
Kemp explained that noises from the pressurizing tanks were at a frequency which caused an on board accelerometer to reset. “And it was super-interesting, because the entire XYZ didn’t reset, just one of the axes reset. Which was actually an undocumented feature in the sensor that we were using.”
“And if that had happened in a flight, it could have given our guidance computer data that could have caused really, the consequences of that could be very difficult to predict. And you don’t want a rocket, as it’s lifting off, to have a guidance computer that doesn’t know what direction the thing’s pointed, even for a couple of milliseconds. So we decided the safe thing to do would be to not conduct the launch until we fully reviewed the cause of that issue.”
After the DARPA challenge window closed, the payloads were removed, and Rocket 3.0 reverted to a test flight status. But before another launch attempt could be made, the vehicle exploded on the launch pad in March 2020.
Keeping with the iterative development approach, Astra quickly moved to Rocket 3.1. “We brought one out for the DARPA Challenge, almost launched it. Blew it up by accident. Launched the next one. Launched the next one.”
Rocket 3.1 was the first Rocket 3 series vehicle to fly, lifting off in September 2020. “We were able to quickly build another launcher, which reinforced the idea that this portable launch system was a great strategy. Because we could go back, put it all in containers, rebuild, send it back up there, and then launch again six months later.”
This flight was terminated via a commanded engine shutdown approximately 30 seconds after liftoff. “We had another really complex issue with guidance, where the software system had the rocket clocked in a slightly different configuration. And it was going to fly off course, so we had to turn it off. And so the safety system just turned the engines off and the thing fell out of the sky after about 30 seconds.”
“All the data other than that was perfect. And so we had one line of code in the guidance system that needed to be fixed, but as we scoured all the other data, the engines performed great. The pressurization system performed great. Terminal count performed great.”
And so the teams moved on to Rocket 3.2. While the goal was to make progress towards reaching orbit, the teams were not afraid of falling short, so long as meaningful data was collected to improve the system for the next attempt.
“We didn’t expect that flight to really reach space, and we didn’t expect the upper stage to perform as well as it did because it wasn’t tested and qualified to. I mean, we were really just trying to get the first stage working.”
“When the upper stage lit, and the upper stage flew away, and the guidance system worked beautifully, and we made it to space, we passed the Von Karman line, we kept going, we kept going, we kept going.”
“I’ve never seen more people see the point in their career and the point in their life where they’ve achieved something so incredible that, it was absolutely awe-inspiring.”
In the end, the flight fell short of achieving orbit due to a fuel mixture issue on the rocket’s second stage. Kemp explained that, had Astra targeted a different orbit requiring a little less performance, the vehicle could have achieved orbit.
“And certainly it could have achieved the orbit that we had targeted if we didn’t have 9% residual liquid oxygen on the upper stage.”
Astra has since achieved a “near perfect” liquid oxygen and kerosene depletion on a full duration burn at their California factory and testing facility.
Now, Astra is preparing to reach orbit for the first time with Rocket 3.3. In addition to correcting the fuel mixture problem, Astra has again increased the size of the rocket and will be placing customer payloads on board.
“Between Rocket 3.2, which flew a few months ago, and Rocket 3.3, we’ve increased its length by five feet. Because additional efficiencies in the engines mean that we can actually burn more fuel. And so because the diameter was already large enough, we could simply extend its length.”
Following the Rocket 3.3 launch, the “launcher,” referring to the launch mount and erector on the ground, will remain in Kodiak to support more flights while Astra will send another launcher to a new site to support missions beginning later this year.
“We were actually only planning on making about eight of these rockets. So we’ve increased the production run for the Rocket 3 series to a dozen. And we’ll be flying those monthly starting in the fourth quarter. And then that monthly rate will ramp up to weekly with the Rocket 4 series starting next year.”
Setting Astra apart from competition
Kemp described how he sees Astra’s role as a smallsat launch provider compared to other small offerings as well as large rockets.
“I think there are some just fantastic companies out there that are building massive rockets that will have the ability take large amounts of cargo up into space. These are very large rockets, getting larger in a lot of cases. And we think that’s a critical piece of infrastructure when you’re going to Mars, putting large amounts of things in one place in space.”
“But what we’re seeing is, we’re seeing hundreds of companies that have all formed over the past five, ten years. They all have different satellites. They’re all very small. They all want to go to different places in space, typically from different places on Earth, all on different schedules.”
“So you can think of Astra of just filling in that gap in the market where we can access anywhere in space, on any schedule, from anywhere on Earth.”
In order to make this offering at low cost, Kemp says reusability will not play a part at Astra. “The way to optimize the economics of a high-volume, low-cost system like the one that we’re building is to not attempt to reuse the system.”
“If it costs millions of dollars to make the rocket, you totally want to reuse it, and so I can see why companies like Rocket Lab — when they have a Ferrari, carbon fiber, expensive thing — totally don’t want to throw that away. So I see why they’re going down that path. But for Astra, where our target is to make the entire rocket for a couple hundred thousand dollars, it just doesn’t make any sense for us.”
In addition to Rocket Lab, which was the first of a new wave of commercial small launch providers to achieve orbit, Kemp compared Astra’s costs to that of Virgin Orbit, which achieved orbit for the first time in January 2021.
“How do we go and operate a system globally from as many spaceports as possible? How do we manufacture, some day, thousands of rockets a year and truly democratize access to space? And so who’s competing with us on that front? It’s not clear. We have Virgin Orbit, with a vehicle that they sell for $12 million. That’s three times more expensive. Carbon fiber. You need to deploy a 747 every time you fly it. With twelve shipping containers behind it. That’s our competitor.”
Astra recently won a launch contract from NASA for the TROPICS mission, in which Astra beat not only Rocket Lab and Virgin Orbit, but also SpaceX’s Starship system. Kemp says the team was both surprised and humbled to be competing, and winning, against Starship.