Talk:SpaceX Dragon 2/Design

Design

The Dragon 2 is primarily composed of three parts — the nosecone, the capsule, and the trunk. The nosecone "protects the vessel and the docking adaptor during ascent and reentry"; pivots on a hinge to enable in-space docking, and returns to the covered position for reentry and future launches. The capsule can carry crew and pressurized cargo to and from the International Space Station (ISS). It also houses the engines, thrusters and docking ports. While the trunk is discarded after every flight and contains the solar arrays, heat-removal radiators, in addition to any unpressurized cargo. The trunk also provides aerodynamic stability during emergency aborts.

Payload capacity

Dragon 2 can carry 7 astronauts or 6,000 kilograms to the International Space Station. It can return 3,000 kilograms back to Earth. Dragon 2 is only planned to fly crew on the first flight of a particular capsule, while following flights would carry only cargo.

Reusability

Near the end of every mission, the spacecraft separates into the capsule and the trunk. While the trunk is left in orbit, the capsule returns any crew and cargo back to Earth. The capsule is designed to cope with re-entry heating using a third-generation PICA-X heat shield, and be recovered using four main parachutes. It can be flown multiple times.

Propulsion

Crew Dragon has eight side-mounted SuperDraco engines, clustered in redundant pairs in four engine pods, with each engine able to produce 71 kilonewtons (16,000 lbf) of thrust Each pod—called a "quad" by SpaceX—also contains four Draco thrusters. The Draco thrusters are used for on-orbit propulsion, while the SuperDraco engines serve as the launch escape system.

The engines and thrusters are powered by hypergolic propellants. Composite-carbon-overwrap titanium spherical tanks hold the helium used to pressurize engines and also for the SuperDraco fuel and oxidizer.

The SuperDraco engine has a 3D-printed inconel combustion chamber made using a process of direct metal laser sintering. Engines are contained in a protective nacelle to prevent fault propagation if an engine fails.

Controls

Unlike most spacecrafts, Crew Dragon's primary interface consists of three touchscreen displays.

Docking

Unlike the original Dragon, which used berthing (a non-autonomous means to attach to the ISS that was completed by use of the Canadarm2 robotic arm), Dragon 2 is able to autonomously dock to International Docking Adapters on the ISS. Though pilots retain the ability to park the spacecraft using manual controls if needed.

Space suit

Main article: Space suit § SpaceX suit

The spacecraft can be operated in full vacuum, and the spacecraft will be able to return safely if a leak occurs "of up to an equivalent orifice of 0.25 inches [6.35 mm] in diameter." To protect the crew members during rapid cabin depressurization, they will wear a custom space suit. It is intended to be worn only inside a spacecraft for intra-vehicular activities (IVA). A test "dummy" named Ripley, which was wearing the suit and contained multiple sensors, was launched and docked to the ISS in the DM-1 Mission.