SpaceX Falcon 9: How Elon Musk's Rocket Is Winning the Reusability Race

The Falcon 9 gets a notable vouch of confidence. 

SpaceX’s Falcon 9 rocket has helped set a new bar for rocket reusability, and now the European Union wants in on the action, according to some recent funding projects. The EU-based public-private partnership Retro Propulsion Assisted Landing Technologies, or RETALT, kicked off its launch earlier this month with a rather unusual admission.

“What is state-of-the-art in the USA is only in its beginnings in Europe,” the press release reads. “The consortium is determined to accept the challenge and to become important players in this game-changing technology.”

To rectify the problem, five European companies and the German space agency are pooling resources to develop reusable rocket technology of their own, according to the press release published June 14. In a Wednesday tweet, SpaceX CEO Elon Musk praised the news.

“Good to see this,” Musk wrote in response. “Splitting interstage into 4 sections will have some challenges, but could work.”

Falcon 9 launch
The Falcon 9 Launches

Developing reusability has been one of SpaceX’s signature breakthroughs. The key success may have been the Falcon 9’s streak of 12 straight “return to launch site” landings in a row until a rare misstep last December, reported the Verge. The company has successfully landed 43 cores in total, ever since its first failed attempt in 2013.

This is helping bring down the cost of space flight. Reusing a Falcon 9 booster saves around $46.5 million of the estimated $62 million launch price. Musk has compared not saving the booster to not saving an airplane and asking everyone to parachute out near the destination.

It’s a great idea, but an incredibly tricky challenge. It involves bringing the booster back to Earth after liftoff and reducing its speed so it can safely land on the pad. That’s easier said than done.

Reusing Rockets: How Europe Plans to Take On SpaceX

Concept sketch of the RETALT-1 spacecraft.
Concept sketch of the RETALT-1 spacecraft. Each section shows from left to right launch, stage separation, first stage descent, first stage landing.

RETALT is a group of five European companies: Almatech, Amorim, CFS Engineering, Deimos, and MT Aerospace. It also includes Deutsches Zentrum für Luft- und Raumfahrt e.V., or DLR, Germany’s major research establishment in this field. The European Commission, the executive of the European Union, has given the project €3 million ($3.4 million) as part of the Horizon 2020 research framework.

The consortium has two concepts. The first is RETALT 1, seen in the image above. That’s explicitly described by the team as “similar to the Falcon 9 developed by SpaceX.” This is a two-stage-to-orbit craft that vertically takes off and lands. The plan is to design a vehicle that can take 30 tons to a low-Earth orbit of around 211 miles, separating from the second stage at 68 miles at a speed of Mach 7.1. By comparison, the Falcon 9 can lift just under 23 metric tons to low-Earth orbit.

The RETALT 1 uses the Vulcain 2 engine, which uses liquid oxygen and hydrogen. The first stage uses seven of these engines. Upon return it uses a deployable interstage as seen in the above image, unlike the Falcon 9 that uses grid fins to stabilize on return.

RETALT 2, showing launch and descent.
RETALT 2, showing launch and descent.

The second concept is a single stage to orbit vehicle compared to the McDonnell Douglas DC-X. It is designed for use in suborbital missions or taking smaller payloads to low Earth orbit.

Reusing Rockets: Why SpaceX Won’t Be Chasing RETALT

After Musk posted about the RETALT project, a Twitter user called “C3LT” followed up with a question about whether major design changes could come to the Falcon 9’s “Block 5” design. Musk responded by declaring that “there will be no Block 6” as the firm is “moving to Starship architecture.”

This shift is not surprising. The ambitious Starship, a stainless steel behemoth designed to ferry the first humans to Mars, is designed with a number of cost-cutting measures in mind to make it profitable. The goal with Starship, as outlined in September 2017 when it was still known as “BFR,” is “to make our current vehicles redundant…we want to have one booster and ship that replaces Falcon 9, Falcon Heavy, and Dragon.”

The new Starship images.
The Starship on Mars.

SpaceX has set itself the ambitious goal of producing a new Raptor engine every 12 hours by the end of the year. Each Starship will use around 38 engines, meaning the company is putting a lot of resources into getting the behemoth ready to take on all of SpaceX’s future missions.

As RETALT starts to take flight, SpaceX may have already moved on to the next big thing.

Media via SpaceX, RETALT, Elon Musk/Twitter