The Dragon spacecraft is another successful accomplishment of SpaceX. Developed as part of NASA's plan to hand over space station flights to American companies, Dragon has a capsule and a trunk. Within its 13 ft diameter and 328 cubic feet of volume, the Dragon capsule is capable of carrying up to 7 passengers. The trunk, with its 1300 cubic feet, carries unpressurized cargo and supports the spacecraft during ascent.
The trunk’s latest design incorporates the solar panels over half of its side surface, and removes the roll-out solar panel model that needed mechanical parts. These solar panels provide power to Dragon spacecraft during flight and while on the ISS. The trunk also has fins that provide stability during launch abort and provides the Thermal Control System radiator to reject the heat from the vehicle to space. The trunk remains attached to the Dragon until shortly before reentry into Earth’s atmosphere.
The Dragon spacecraft is also equipped with 16 Draco thrusters, each capable of generating 90 pounds of force. Located in the lower portion of the capsule, these facilitate orbit adjustment and attitude control of the spacecraft during the mission.
The Dragon spacecraft can be launched in its cargo configuration, with no seats, to send supplies to the International Space Station (ISS). In its crew configuration and with no cargo, the capsule could carry up to 7 passengers. This number is reduced to 2-4 depending on the cargo and science experiments part of the mission. In the crew configuration, the Dragon capsule also includes cockpit controls, and astronaut life support systems or Launch Abort System (LAS), which separates the capsule from the launch vehicle in case of an emergency that requires aborting the launch.
The first cargo mission to the ISS under the Commercial Resupply Services contract (CRS-1) was launched on October 8th, 2012. For this initial flight, the Dragon spacecraft was captured with a robotic arm of the ISS. After 20 resupply missions, the last capsule captured this way arrived at the ISS on March 9th, 2020. Subsequent Dragon capsules were able to dock themselves to the ISS.
The autonomous docking system was key to ready the Dragon capsule for its human flight. On March 2, 2019, SpaceX launched the unmanned mission Crew Dragon Demo-1 C204 atop a Falcon 9 rocket from Cape Canaveral, FL, which successfully docked in the ISS using the autonomous rendezvous and docking system on March 3, 2019. This demonstration mission also tested the undocking, re-entry, splashdown, and recovery steps. This mission provided the needed data to qualify the spacecraft for human transportation.
On May 30, 2020, Nasa astronauts Doug Hurley and Bob Behnken participated in the Demo-2 mission aboard of the Crew Dragon Endeavour This was the first crewed flight from the United States to the ISS after the retirement of the NASA Space Shuttle program, with its last flight on July 2011. This also was the first crewed orbital spaceflight by a private company. The mission Demo-2 C206, originally planned to last only two weeks, was extended to 63 days to provide the needed support for the ISS.
