Deep inside SpaceX’s Hawthorne, California rocket factory, the Crew Dragon capsule – believed to be C207 – assigned to the company’s operational astronaut launch debut (Crew-1) is in the late stages of final integration. A photo provided alongside the news confirms that the Crew Dragon is nearly complete. Aside from the installation of body panels and several other tasks that will be completed once the ship arrives in Florida, capsule C207 is already fully outfitted with a heatshield, windows, Draco maneuvering thrusters, SuperDraco abort thrusters, parachute deployment hardware, and much more.
According to Benji Reed, SpaceX Director of Crew Mission Management,
SpaceX’s Crew-1 operational astronaut launch debut remains on track to
launch no earlier than late September. Capsule C207 and its upgraded
trunk section are also reportedly on track to head from California to
SpaceX’s Florida launch facilities in time to support that schedule and
could ship east just two or so weeks from now.
The only major (known) difference between SpaceX’s newest Crew Dragon
and the spacecraft (C206) currently in orbit is the inclusion of
upgraded solar panels on the ship’s expendable trunk section.
Effectively an aerodynamic shroud and mounting adapter for the capsule,
the aft trunk also hosts radiators for thermal management and a unique
conformal solar array to supply the spacecraft with power while in
orbit. It’s unlikely that Crew Dragon will ever utilize it but the trunk
also serves as an unpressurized cargo fixture. That will allow Cargo
Dragon 2 (based on Crew Dragon) to carry much larger external payloads
to the International Space Station (ISS) once it starts launching later
this year. Prior to its retirement in April 2020, the original Cargo
Dragon spacecraft used a similar trunk section to deliver unpressurized
cargo to the ISS more than a dozen times.
According to several comments made by NASA and SpaceX over the last few months, the only known limit to the first private spacecraft in history to launch astronauts into orbit (Crew Dragon C201) is its trunk’s solar cells. Seemingly discovered during some combination of ground testing and Crew Dragon’s uncrewed Demo-1 launch debut, the current version of the trunk suffers gradual solar cell degradation while in orbit, slowly reducing the amount of power the solar array can produce. Eventually, power output could degrade to the point that Crew Dragon would no longer be able to effectively charge its battery – a catastrophic failure if astronauts were aboard and the spacecraft free-flying.
The amount of time SpaceX’s Demo-2 Crew Dragon spacecraft can spend in orbit was actually limited ~120 days by that solar cell degradation. On a nominal operational astronaut launch, Crew Dragon will need to spend at least half a year (~180 days) docked to the ISS. Demo-2 was originally expected to last just a few days or weeks at most, so that shortfall was of minimal concern, but it did inherently imply that a sturdier solar array was inevitable and right around the corner.
Once Crew Dragon capsule C207 arrives in Florida, it will join Falcon 9 booster B1061 and likely be joined by the expendable upper stage and trunk section shortly thereafter. First and foremost, however, SpaceX needs to safely return Crew Dragon C206 and NASA astronauts Bob Behnken and Doug Hurley to Earth before it can launch Crew-1. As of now, the spacecraft is scheduled to depart the ISS as early as 7:34 pm EDT (00:34 UTC) on August 1st, followed by reentry and splashdown roughly 18 hours later.
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