Crew Dragon Demo-2: Endeavour's Complete Crewed Test Flight

Crew Dragon Demo-2 was a flight test in the National Aeronautics and Space Administration's (NASA) Commercial Crew Program. Space Exploration Technologies Corporation (SpaceX) supplied the Falcon 9 rocket, Crew Dragon spacecraft and associated operating systems. The mission linked launch, orbital flight, space station docking, reentry and recovery at sea into a complete validation process, building evidence for routine crew transportation.

Douglas Hurley served as spacecraft commander, while Robert Behnken served as joint operations commander, responsible for operations including rendezvous, docking and departure from the station. Tests covered manual control, life support, control panels, thermal protection and parachutes, as well as the spacecraft's safe-haven configuration while docked, equipment stowage, putting on and removing spacesuits, and living conditions. The spacecraft had to suit crew operations and work together with ground control and recovery teams.

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The commercial crew system went through manufacturing, qualification and uncrewed flight tests before reaching the crewed validation stage. NASA reported to its advisory council in May 2020 that hardware testing and review of certification documentation were still progressing; personnel also supplied the development team with user feedback during training and testing. Preparing for crewed flight involved both machine performance and operating procedures.

On January 19, 2020, SpaceX conducted an in-flight abort test from Launch Pad 39A at Kennedy Space Center. The abort was triggered about 84 seconds after liftoff. SuperDraco engines pulled the spacecraft away from the launch vehicle, after which Draco thrusters adjusted its attitude, its Mark 3 parachutes deployed and it splashed down. Department of Defense rescue personnel also simulated crew rescue, and experience from the entire sequence informed preparations for Demo-2.

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At 3:22 p.m. Eastern Daylight Time on May 30, 2020, Hurley and Behnken launched aboard a Falcon 9 from Kennedy Space Center in Florida. This marked the return of astronaut launches to orbit from United States soil after the space shuttle's retirement. Once in orbit, the two named their spacecraft Endeavour, commemorating the shuttle on which each had made his first flight.

About 19 hours later, on May 31, the spacecraft docked automatically at the forward port of the International Space Station's Harmony module. The two astronauts joined Expedition 63, working with commander Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner. Arrival at the station also placed the spacecraft in an environment for testing prolonged docking and support of crew activities.

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Hurley and Behnken spent 62 days aboard the station, taking part in scientific experiments, maintenance and public outreach. The President's annual aeronautics and space report recorded that the pair added more than 100 hours of work to research in orbit and supported four spacewalks. The additional crew working time made a practical contribution to maintaining the station's experiments and facilities.

Behnken and Cassidy conducted four extravehicular activities together, replacing lithium-ion batteries for two power channels at the far starboard end of the station's truss and running power and Ethernet cables. They also removed fixtures used for ground handling of solar arrays before launch, installed storage facilities related to robotic operations, and removed some shielding panels and covers in preparation for a later commercial airlock.

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After its docked stay, Endeavour departed the station automatically and completed reentry. At 2:48 p.m. Eastern Daylight Time on August 2, or 1:48 p.m. Central Daylight Time near the splashdown site, it came down in the Gulf of Mexico off Pensacola and was recovered by SpaceX. After returning ashore, the two astronauts flew to Houston.

The flight lasted about 64 days and completed 1,024 orbits of Earth. The 62-day station stay and roughly 64-day mission covered different phases. The returning capsule was transported to a processing facility in Florida for inspection; teams analyzed data from the entire flight to evaluate the rocket, spacecraft, ground systems, and docking, splashdown and recovery operations.

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The report of the NASA Aerospace Safety Advisory Panel's public meeting on October 1, 2020 confirmed that Demo-2's operational testing and mission-success objectives had all been met. Power, propulsion, life support and thermal control systems had performed as expected. The postflight review also identified details needing improvement.

Ablation in the area connecting the spacecraft's heat shield to its unpressurized trunk was greater than the designers had wanted. A modified design had been tested at the Ames Research Center's arc-jet facility. The drogue parachutes deployed lower than expected but still within permitted limits; SpaceX accordingly adjusted how GPS altitude and barometric altitude were used in deployment logic. Recreational boats gathering during recovery also prompted NASA, the Coast Guard and SpaceX to strengthen warnings and coordination in the recovery area.

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