When SpaceX’s Starship launched from the Texas coast in the summer of 2023, it marked a milestone that aerospace engineers have been talking about for decades, but few expected to witness so soon. The towering stainless steel rocket, taller than a 30-story building, ignited all 33 engines and rose into the sky. Although the mission did not unfold perfectly, it proved that the concept could be realized.
Its importance became even clearer during Starship’s fifth integrated flight test, when a returning super heavy booster was successfully captured in midair by the launch tower’s giant mechanical arm. This demonstration signaled the beginning of a new era of reusable spaceflight.
Starship is ultimately intended to carry objects weighing more than 100 tons into low-Earth orbit while remaining fully reusable. If SpaceX achieves that goal, it could become the most powerful and cost-effective launch vehicle ever built. As a result, space agencies and aerospace companies are now focusing less on whether Starship will reshape the industry and more on how they should respond.
Independent analysis confirms Starship’s capabilities
Researchers at the German Aerospace Center (DLR) recently completed one of the most comprehensive independent evaluations of Starship to date. Rather than relying on specifications published by SpaceX, the team reconstructed the rocket’s performance by extracting telemetry from publicly available videos of the first four integrated flight tests. They analyzed data second by second and built and validated their own performance models.
Their findings suggest that Starship’s capabilities are both realistic and impressive.
The current fully reusable version of Starship could carry around 59 tons into low Earth orbit, according to the analysis. This is roughly equivalent to what the Falcon Heavy could fire if no boosters were recovered.
The researchers also evaluated SpaceX’s planned next-generation Starship. The Starship is expected to have larger propellant tanks and more powerful Raptor 3 engines. Their model projects a reusable payload of approximately 115 tons to low Earth orbit, with up to 188 tons possible in a disposable configuration. This would exceed the lift capacity of NASA’s legendary Saturn V rocket.
European RLV C5 takes a different approach
The study also introduces a European concept for a superheavy rocket called RLV C5. Rather than attempting full reuse from the beginning, the design focuses on partial reuse while maximizing efficiency.
The concept combines a reusable winged booster and a disposable upper stage from DLR’s long-running SpaceLiner program. It uses liquid hydrogen and liquid oxygen, a more efficient propellant combination than the methane and oxygen used in Starship’s Raptor engines.
Unlike Starship, the RLV C5 booster does not perform a powered vertical landing. After re-entering the atmosphere, it glides on its wings and is captured mid-air by a large subsonic aircraft. Although this method of recovery sounds futuristic, researchers claim it has important benefits. Boosters do not need to reserve propellant for landing, so more fuel can be used to reach orbit.
Relationship between efficiency and maximum load capacity
This study highlights the different engineering priorities behind the two vehicles.
Starship’s launch weight is more than three times that of the proposed RLV C5. Much of that additional mass comes from the hardware required for full reuse, such as thermal barrier tiles, landing propellant, structural reinforcement, and other recovery systems.
As a result, only about 40% of the mass that Starship puts into orbit is a useful payload. By comparison, the partially reusable RLV C5 would devote approximately 74% of its mass to the payload. It won’t match Starship’s massive lifting capacity, but it will be far more efficient.
Different mission, different solution
DLR researchers emphasize that the two rockets are not direct competitors, but different solutions to different problems.
Starship’s vast payload capacity and planned rapid reuse make it ideal for ambitious projects such as lunar bases, Mars missions, and large satellite constellations.
RLV C5, on the other hand, is intended to provide Europe with an independent super-heavy launch capability without the huge costs of developing a fully reusable system on the fly. Because it is based on technology already being researched through the Spaceliner program, researchers believe this could serve as an intermediate step before Europe eventually develops a fully reusable launcher.
concept and flying rocket
The study also acknowledges an important reality.
Starship has already conducted flight tests, despite continuing technical challenges. RLV C5 remains a concept on paper, and it will take many more years of development to turn it into a working launch vehicle.
Starship itself still faces major engineering hurdles. During the fourth comprehensive flight test, damage to the thermal protection system was severe and the design had to be significantly modified. Achieving rapid, reliable, and fully reusable operations is one of the biggest outstanding challenges behind rocket long-term economic models.
Still, lead author Moritz Haverhold and colleagues conclude that “RLV C5 provides an effective path for Europe to independently develop a partially reusable superheavy launch capability.”
Whether the future belongs to fully reusable giant systems like Starship or more efficient partially reusable systems, research suggests there may be multiple successful paths to next-generation spaceflight.
