Today American aerospace manufacturer SpaceX celebrated a successful 10 km test of their latest Starship Prototype SN10 at their Boca Chica launch site in Texas. This test aims to test the novel “bellyflop” descent and the “flip maneuver” landing burn to further their efforts to send humans to Mars.
The development of this vehicle began in 2012 with SpaceX CEO Elon Musk’s announcement as the “Mars Colonial Transporter”. The name and design of the vehicle has gone through many iterations. Testing began in earnest with the April 2019 test article, Starhopper, a glorified water tank with a rocket engine and landing legs. Several tests of other partial mockups have flown, leading to the full-size tests of two Starship prototypes, SN8 and SN9, that were conducted that ending in losses of their vehicles. Like their Falcon 9 rockets, the Starship will launch and land vertically, thus lowering the cost of access to orbit. Unlike their prior efforts, the Starship will use flaps on the rocket’s sides to slow and control the descent, falling horizontal like a skydiver, which is known as the “bellyflop”. This method of control has been demonstrated in the prior two tests with great ease. Once close to the surface, the rocket will fire 3 of its engines to flip the rocket from the horizontal to vertical and slow the rocket to a controlled landing. This step has been the point of failure in the previous two tests. SN8 was lost due to loss of fuel flow, which caused some of the engines to burn a bright green exhaust before crashing in an almost perfect landing. While SN9 only had one of its three engines reignited, resulting in a crash. SN10 completed all the steps and set down on the landing pad, albeit a bit crooked, most likely due to the landing legs’ incomplete deployment. The prototype was lost after a residual fire burnt for 3 minutes and resulted in the rapid unscheduled disassembly, a favored euphemism in the SpaceX community.
The Starship is a fully reusable orbital launch vehicle that will lift over 100,000 kg to low earth orbit, about four times the retired Space Shuttle’s capacity. This launch system consists of two parts a Super Heavy Booster and the Starship orbiter. These vehicles use the new Raptor engines, which are the first full-flow staged-combustion engines to be flown. These engines burn methane and oxygen; methane is essential to their goal of going to Mars as the fuel for return trips will be generated on the red planet. Six of these powerful engines will be used in the Starship, while the Super Heavy will use 28. Orbital refueling will be used to refill the orbiter for the intended trips to Mars or any other mission this vehicle will conduct.
The system is a departure from the traditional construction methods of the aerospace industry. Rather than using a lighter material, both Starship and Super Heavy will be constructed from stainless steel. The building of these components is being done in hangers at the Boca Chica launch site, with the engines being shipped in from other SpaceX facilities.
The process of development is rapid iterative prototyping and testing regime. The initial tests of the Raptor engines on a vehicle occurred in April of 2019. Several hops have occurred with incomplete versions of the Starship prior to the testing of the “bellyfop” and “flip maneuver”. Only the Starhopper test article has been left intact and sits at the launch facility. Nine other Starships have been numbered by the company, with three canceled due to construction methods changes. SN11 is currently awaiting roll out to the pad from their integration building known as the Highbay. SN15 through SN19 are in various stages of construction at the site. Construction of the Super Heavy began in the fall of 2020, with 2 boosters named BN1 and BN2. As of February 2021, the stacking of BN1 has already started to test the vehicle with as little as 2 Raptor engines. As the Super Heavy does not include any unproven techniques from the routine Falcon 9 booster operations, this component’s testing should progress swiftly. Founder of SpaceX, Elon Musk, intends to send the Starship to orbit in 2021. Plans for a human-crewed mission to go around the moon called dearMoon funded by Japanese billionaire Yusaku Maezawa is tentatively scheduled for 2023.
The Starship itself will be the basis for at least 4 variants. Starship is a vehicle that can conduct missions to Mars or low earth orbit. This version can also be used alone to provide point-to-point space flights around the planet. This would drastically lessen the planet’s flight times, cutting the record longest flight, Singapore to Newark, New Jersey, from 18.5 hours to 30 minutes. A satellite delivery version could be used to deploy or remove satellites from orbit and provide a solution to combat space debris’s ever-increasing issue in low earth orbit. A tanker version is proposed to refuel the Starship itself to provide the fuel for missions. The Lunar Lander version is currently being evaluated, and other proposals to provide a vehicle for astronauts to land on the moon for NASA’s Artemis program. This version would have a docking port on the nose of the craft, lack the aerodynamic surfaces and heat shielding, be painted white to reduce thermal loads, and have smaller engines placed high on the ship to minimize dust effects of landing.