Assuming good weather and a smooth final few weeks on the International Space Station, astronauts Doug Hurley and Bob Behnken are scheduled to undock from the orbiting research outpost Aug. 1 and return to Earth the next day to wrap up a 64-day test flight of SpaceX’s Crew Dragon spaceship.
NASA Administrator Jim Bridenstine confirmed the target dates for the Crew Dragon’s undocking and splashdown in a tweet Friday.
A few hours after departing the space station, the Crew Dragon will fire its Draco thrusters for a braking burn and re-enter the atmosphere, targeting a parachute-assisted splashdown at sea.
“Splashdown is targeted for Aug. 2,” he tweeted. “Weather will drive the actual date. Stay tuned.”
NASA and SpaceX are assessing return zones in the Atlantic Ocean and the Gulf of Mexico.
Officials originally selected landing sites in the Atlantic east of Cape Canaveral and Jacksonville, and a location in the Gulf of Mexico south of Pensacola, Florida. Last month, NASA said officials were evaluating additional candidate locations for the Crew Dragon’s splashdown off Daytona Beach, Tampa, Tallahassee and Panama City.
The additional options would give mission managers more flexibility in deciding when to approve the Crew Dragon’s undocking and re-entry.
The final selection of a landing site will hinge on weather and sea states. Assessments of climatology suggest conditions in the Gulf of Mexico have a higher likelihood of being favorable for splashdown in early August, sources said.
Hurley and Behnken will be the first NASA astronauts to return to Earth for a water landing since Tom Stafford, Deke Slayton and Vance Brand splashed down July 24, 1975, in an Apollo command module to end the Apollo-Soyuz mission, which included the first docking between U.S. and Russian spacecraft in orbit.
The Crew Dragon spacecraft launched with Hurley and Behnken on top of a Falcon 9 rocket May 30 from NASA’s Kennedy Space Center in Florida. It was the first launch of astronauts into orbit from U.S. soil since the last space shuttle launch July 8, 2011.
The crew capsule autonomously docked with the International Space Station on May 31, allowing Hurley and Behnken to join space station commander Chris Cassidy and Russian cosmonauts Anatoly Ivanishin and Ivan Vagner.
The primary goal of the Crew Dragon’s first mission with astronauts — named Demo-2, or DM-2 — is to test the SpaceX-built capsule’s performance before it begins regular crew rotation flights to the space station later this year. SpaceX successfully flew an unpiloted Crew Dragon to and from the space station in 2019 before NASA approved the capsule to carry astronauts.
Hurley and Behnken have also assisted the space station’s long-duration crew with experiments, maintenance and other tasks. The Demo-2 mission was originally planned to last no more than a couple of weeks, but NASA announced earlier this year the test flight would be extended to expand the size of the crew on the space station.
At the time, Cassidy was the final U.S. astronaut NASA had booked to fly on Russia’s Soyuz spacecraft, which has been the sole vehicle to carry crews to and from the space station since the end of the space shuttle program nearly a decade ago. That meant Cassidy would have been the only U.S. astronaut on the station for most of the time from April through October, limiting opportunities for research and spacewalks needed to upgrade and maintain the orbiting complex.
With the extended Demo-2 mission, Behnken has joined Cassidy on three spacewalks since June 26 to finish replacing batteries on the space station’s solar power truss. One more spacewalk by Behnken and Cassidy is scheduled for Tuesday, July 21.
NASA says the Crew Dragon has performed well since its launch. While docked at the space station, the capsule has been put into hibernation and awakened several times to check its availability to serve as a lifeboat for the crew if they had to evacuate the orbiting research lab in an emergency.
Ground teams have also monitored the performance of the Crew Dragon’s body-mounted solar arrays, which can degrade over time due to the harsh environment in low Earth orbit. So far, the power-generating arrays have performed better than predicted.
Last week, four of the space station crew members boarded the Crew Dragon to assess the ship’s ability to accommodate a four-person crew in orbit, particularly when astronauts will be required to sleep on the vehicle during the transit to and from the space station.
If the Demo-2 mission returns to Earth in early August, SpaceX and NASA will press ahead with preparations for the first operational Crew Dragon mission. That flight, designated Crew-1, is currently scheduled to launch from the Kennedy Space Center in mid-to-late September.
Steve Stich, NASA’s commercial crew program manager, said last month that engineers will need around six weeks evaluate data from the Crew Dragon test flight before formally certifying the capsule as ready for operational missions.
The brand new Falcon 9 first stage booster for the Crew-1 mission arrived Tuesday at Cape Canaveral for launch preparations. The Crew Dragon spacecraft for the Crew-1 mission will arrive in the coming weeks.
NASA astronauts Mike Hopkins, Victor Glover, Shannon Walker, and Japanese astronaut Soichi Noguchi are training for the Crew-1 mission. Noguchi, a veteran of two previous space missions, will become the first astronaut to launch on the space shuttle, Russia’s Soyuz rocket, and SpaceX’s Falcon 9.
NASA has ordered six crew rotation flights on the Crew Dragon spacecraft through 2024, each carrying four astronauts to and from the space station on expeditions lasting as long as 210 days. SpaceX also has agreements with Axiom Space and Space Adventures, two commercial space companies, to fly private citizens into orbit on shorter-duration Crew Dragon missions beginning as soon as late 2021.
SpaceX developed the Crew Dragon under contract to NASA, but the company is free to use the spacecraft for commercial flights without NASA involvement.
NASA has a similar contract with Boeing for development of the Starliner crew capsule, which has yet to fly with astronauts. An unpiloted Starliner test flight was cut short before docking with the space station in December, and Boeing plans to fly a second demonstration mission later this year before a test flight with a crew on-board in early 2021.
There are several modifications to the capsule SpaceX is building for the Crew-1 mission, although major components such as the capsule’s life support system and guidance, navigation and control systems are largely unchanged from the Demo-2 configuration.
“The Crew-1 vehicle can land in a little bit higher wind state,” Stich said in a press briefing May 31. “SpaceX has changed some of the outer composite panels to make that a little stronger.”
“It also has the capability not only dock to the forward port of the space station, but it can go to the zenith (space-facing) port as well, so it has that capability, and it has a couple other features,” Stich said.
NASA and SpaceX have not released the official wind and sea state constraints officials will use to determine the final schedule and location for the Demo-2 splashdown.
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