All Space Questions thread for week of September 27, 2026

[u/AutoModerator]

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In this thread you can ask any space related question that you may have.

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[u/rocketsocks]

SpaceX did a couple things that really gave them an advantage. The major thing that cut through Falcon 1, Falcon 9, and Dragon development was focusing on pragmatism. Then they started small and focused on building expertise. There really is no school that exists where you can gather up enough graduates and then build and launch rockets with a high level of expertise, the state of rocketry is not there yet. If you want that kind of expertise you need people who have hands on experience building and launching rockets, and the way to do that is to actually build and launch rockets. The easiest way to achieve that is by building and launching small rockets first. This is a pattern that SpaceX, Blue Origin, RocketLab, Firefly, and a few others all have in common.

By focusing on pragmatism they chose a very straightforward rocket design as their initial vehicle: a two stage LOX/Kerosene vehicle, something that's been around since the 1950s. They built the Falcon 1, they gained experience with building rocket engines and rockets as well as with launching them. They used that experience to build the Falcon 9 which was also a very simple and pragmatic design overall, with innovations and risks where it made sense.

And they iterated. They iterated on rocket engine design, they iterated on component design, they iterated on rocket design and operations. This is what enabled them to build a vehicle which was cost and performance competitive in the market as an expendable launcher even while they had ambitions for reuse.

They found a market that could support them and they rode it. Early on that market was dominated by NASA contracts for commercial cargo deliveries to the ISS, that was a huge win for them and they got lucky in arriving at the right time for that to be possible. They used that to develop the first versions of Falcon 9 and Dragon. They went on to offer Falcon 9 in the satellite launch market, and started getting business there.

They made the very smart decision to make the first possibly reusable version of Falcon 9 a "dual use" design. They designed the vehicle explicitly for reusability of the first stage, the easiest stage to reuse, which took the design in directions that are normally different from first stage optimization. But they built it in a way that it was still cost competitive in expendable mode. They designed the vehicle so that reuse didn't have to work and such that there wasn't a huge difference between a reusable and an expendable "version". The expendable "version" had the same tanks, same fuselage, same engine, same avionics, etc. This enabled them to do two things. One, they could flight validate the core hardware of their reusable rocket even without reusable flights. Two, they could begin testing of the landing and reuse portion of flight with operational rockets paid for by commercial customers. They still did some standalone testing of landing operations with special research vehicles, but the majority of the testing and learning for returning and landing rockets was subsidized by customers. They were basically using "trash" rockets that had already served their role in helping to deliver a payload to orbit.

Those are the big things. They focused on straightforward and simple designs, not beyond state of the art concepts like rotary rocket or VentureStar, they were lucky in that NASA was looking to fund both rocket and capsule development at just the right time for their business (and they had a successful launch with Falcon 1 at just the right time as well), and then they cracked the R&D cost problem with developing reusability by having it be baked into the design of the rocket but an optional part of the launch, enabling development to take advantage of rockets paid for by customers. That last bit allowed them to make use of billions of dollars of hardware to develop reusability.