Inside The Startup Building Reusable Rockets

**Aaron Epstein** (0:01)
The team at Stoke Space is going after the holy grail of rocket science.

**Andy Lapsa** (0:06)
Stoke is building fully and rapidly reusable rockets with aircraft-like reusability.

**Aaron Epstein** (0:11)
Today, only this section of rockets can be reused, but Stoke Space is focused on the entire rocket, including a stage two capsule that will finally be able to survive the brutal reentry to Earth. This could open the door to all kinds of new opportunities in space.

**Tom Feldman** (0:27)
I think if you have something that can go up and come back to the place where you want it to go, when you want it to go, I think it is like the iPhone app store moment. People are going to come up with like absolutely crazy ideas for how to take advantage of that.

**Aaron Epstein** (0:44)
So how did two founders go from testing rocket engines in their backyard to solving for one of the hardest problems in space travel? This is the origin story of Stoke Space. Andy and Tom invited me to check out their headquarters in Kent, Washington, just outside of Seattle. It's an area that's quickly becoming known as a hub for space tech startups. What are you building at Stoke Space?

**Andy Lapsa** (1:17)
Building fully, rapidly reusable rockets designed to go to space, through space, and back from space, really to lower costs, improve availability, and improve reliability of access to space.

**Aaron Epstein** (1:29)
Today, there are only around 150 commercial space launches every year. While that's a record for the industry, it's a drop in the bucket compared to where things could go if rockets become fully reusable.

**Andy Lapsa** (1:41)
With only 150 potential transactions, and most of them getting taken up by Starlink, there's just not that much availability. And so there are customers who are willing to pay quite a bit more to get the availability, but to make the space economy more ubiquitous, more diverse, and to enable some of these new verticals and applications, yeah, cost is a huge barrier.

**Aaron Epstein** (2:02)
Describe the hardware architecture itself. Can you walk us through the designs of the Nova and the Andromeda?

**Andy Lapsa** (2:09)
Nova is a two-staged orbit rocket. First stage functions similarly to other rockets. It punches you out of the atmosphere and comes and restarts the engines to land either downrange or back at the launch site. It has one of the highest performing rocket engines in terms of fuel efficiency that's ever been produced. That was a big technical bite for us to bite off as a small company. But I think it's one that is paying off and it's a very important component to long life and rapid reusability. The second stage goes the rest of the way to orbit. Typically, rockets are thrown away completely. In the last few years, the industry has shown the ability to reuse the first stage, which has been transformative. It allowed companies to scale from maybe a dozen or so, 10 to 20 launches per year, now to that 150 number. But the second stage is still thrown away on every single mission.

**Aaron Epstein** (2:59)
That's in large part because the stage 2 capsule is traveling at 17,000 miles per hour as it drops out of orbit. Because of that high speed, it eventually breaks down as it heats up to more than 2,700 degrees Fahrenheit during its descent.

**Andy Lapsa** (3:13)
So these are multi-million dollar machines that not only have to get built, but they have to get tested and acceptance tested to prove flight worthiness. And then they go to space and they get thrown away.

**Aaron Epstein** (3:24)
Here's how their stage 2 or upper stage Andromeda capsule is able to survive reentry. After releasing its payload, it will close up and reenter Earth's atmosphere. At that point, the custom heat shield takes effect. It uses cold liquid hydrogen flowing through a heat exchanger to absorb the extreme heat of reentry. Then 24 small thrusters kick in to help it slow down and land at the right angle.

**Andy Lapsa** (3:51)
What rapid reusability allows you to do is to scale the flight frequency without having to scale your factories and your test facilities and all of the infrastructure that comes with it.

**Aaron Epstein** (4:00)
It seemed like that was the thing that you thought needed to exist in the world. And if somebody else wasn't going to do it, you needed to do it.

**Andy Lapsa** (4:06)
Yeah, that's right.

**Aaron Epstein** (4:07)
How did you get interested in building rockets? Was this something you were always interested in as a kid growing up?

**Tom Feldman** (4:12)
From as far back as I can remember doing SIS rockets in the backyard with my cousins. Then it really just kind of took off from there. Pun not intended. From pretty early on in high school, it was pretty clear that I wanted to do propulsion. It was like, let's do engineering. What's the most badass thing you can do with engineering? Well, it's probably like rocket propulsion.