SpaceX crew capsule returns to Earth, paving the way for human launches

SpaceX’s Crew Dragon spacecraft returned to Earth on Friday with an on-target splashdown in the Atlantic Ocean. Credit: NASA TV/Spaceflight Now

SpaceX’s Crew Dragon spacecraft closed out a six-day test flight in low Earth orbit Friday with an on-target splashdown in the Atlantic Ocean, and officials hailed the ship’s performance before the first mission with astronauts aboard the commercial capsule later this year.

Slowed by four orange and white parachutes, the gumdrop-shaped spaceship splashed down in the Atlantic east of Florida at 8:45 a.m. EST (1345 GMT) Friday, and SpaceX and NASA teams stationed nearby sped toward the capsule, removed a parachute that fell onto the craft after the ocean landing, and readied the Crew Dragon for retrieval. Around an hour after splashdown, ground crews hoisted the spacecraft onto SpaceX’s “Go Searcher” recovery vessel, where the Crew Dragon was expected to be moved into a hangar for the trip back to the Florida coast.

The textbook splashdown Friday punctuated a seemingly picture-perfect mission, a precursor to NASA’s plans to resume astronaut launches on U.S. spacecraft to the International Space Station later this year. Since the last space shuttle landed in 2011, NASA astronauts have rode to space and back aboard Russian Soyuz ferry ships.

“I can’t believe how well the whole mission has gone,” said Benji Reed, director of commercial crew mission management at SpaceX. “Pretty much, I think, at every point, everything has been nailed all the way along, particularly this last piece we were all very excited to see. As we (went) through re-entry, and parachute, drogue deploy, main deploy, splashdown, everything happened just perfectly, right on time, the way that we expected it to.”

Officials from NASA, which has paid SpaceX more than $3 billion since 2010 to develop the Crew Dragon spacecraft, agreed with Reed’s preliminary assessment.

“I don’t think we saw really anything on the (Crew Dragon test flight) mission so far — and we’ve got to do the data reviews — that would preclude us having the crewed mission later this year,” said Steve Stich, deputy manager of NASA’s commercial crew program.

The six-day test flight — known as Demo-1, or DM-1 — was a crucial forerunner before a second orbital test flight — Demo-2, or DM-2, blasts off with NASA astronauts Bob Behnken and Doug Hurley on the next Crew Dragon spacecraft later this year.

The Crew Dragon capsule for the Demo-1 mission launched March 2 atop a SpaceX Falcon 9 rocket rocket from NASA’s Kennedy Space Center in Florida, and reached the space station March 3 with a successful automated docking, the first fully automated link-up with the space station by a U.S. spacecraft.

There were no astronauts on-board, but the Crew Dragon carried an instrumented test dummy named “Ripley,” a nod to the protagonist from the “Alien” film franchise. Ripley rode in one of the Crew Dragon’s four seats, and sensors in the mannequin’s head, neck and spine collected measurements on the g-forces and other conditions astronauts on the ship will experience.

A plush Earth toy also launched inside the Crew Dragon and earned adoration from the space station’s crew, who kept the “Little Earth” inside the orbiting science lab after the SpaceX capsule departed Friday. Behnken and Hurley will bring “Little Earth” back home on their test flight.

The Crew Dragon ferried nearly 450 pounds (204 kilograms) of equipment to the space station — mainly crew supplies — and astronauts planned to pack around 328 pounds (148 kilograms) of hardware and scientific specimens into the capsule’s pressurized cabin for the trip back to Earth.

Canadian flight engineer David Saint-Jacques and NASA astronaut Anne McClain closed hatches leading to the Crew Dragon spacecraft Thursday, setting up for the ship’s undocking from the forward port of the station’s Harmony module at 2:31 a.m. EST (0731 GMT) Friday. The craft fired its Draco thrusters to back away from the space station, then accomplished several additional departure burns to fly a safe distance from the complex in preparation for landing.

The capsule jettisoned its rear trunk at 7:48 a.m. EST (1248 GMT), leaving the power module behind in orbit as the landing module ignited its Draco thrusters again at 7:52 a.m. EST (1252 GMT) for a 15-minute, 25-second braking burn. The impulse from the deorbit burn slowed the capsule’s velocity enough to drop its orbit into the atmosphere, allowing friction from air particles to bring the Crew Dragon back to Earth.

The Crew Dragon spacecraft backs away from the International Space Station after undocking Friday. Credit: SpaceX

After closing a protective nose cone over its docking port and hatch, the capsule encountered the first traces of the atmosphere at 8:33 a.m. EST (1333 GMT) as it flew on a northwest-to-southeast track over the United States, and temperatures outside the Crew Dragon built up to thousands of degrees.

A NASA WB-57 research airplane flying over the Atlantic captured live infrared video of the Crew Dragon spacecraft emerging from the re-entry plasma sheath, then showed the spaceship deploying a pair of drogue stabilization parachutes, followed by the unfurling of four orange and white main chutes.

The parachute deployment was closely watched by SpaceX and NASA engineers. The older cargo-carrying Dragon spacecraft comes down under three chutes, while the heavier Crew Dragon requires four, and parachute anomalies during testing — and on the return of a Dragon supply ship — have put the system under greater scrutiny from engineers and safety managers.

The chutes appeared to work normally Friday, and live video beamed from the splashdown zone showed the capsule — its heat shield blackened from the fiery re-entry — descending under a morning sun before splashing down more than 250 miles ( 400 kilometers) northeast of Cape Canaveral, roughly due east from the Florida/Georgia border.

“All of these gazillions of tests that we’ve been doing on parachutes, all of the analysis and work that we’ve done on understanding the aerodynamics of re-entry and coming home, everything was just wonderful,” Reed said after the splashdown.

Stich, a former space shuttle flight director, sounded a repeating refrain the Crew Dragon’s Demo-1 flight: It was “phenomenal.”

“It was a great dress rehearsal for Demo-2 (the crew test flight),” Stich said. “We learned a phenomenal amount in the pre-launch timeframe, about how to load the vehicle, and thinking forward to how we’ll put the crews in the vehicle. The ascent profile for this flight, we practiced the exact profile that (astronauts) will fly very soon. We had the abort system, the crew escape system in Dragon, actually enabled for this flight, and we were able to see how that worked, and we’ll get the data back and look at those triggers and how it performed.

“On orbit, we got a lot of great data on the vehicle in terms of the thermal performance, power performance,” Stich said. “The vehicle really did better than we expected, and then the rendezvous was phenomenal as we came in (and) checked out those sensors. The link to space station worked, the command link… And then having a real precise docking and seeing how the docking system performed, that was phenomenal.”

The return trip from the space station went just as well, Stich said.

“Today, the undocking, watching how those systems performed, that went flawlessly,” he said. “It’s a very tight sequence between undocking and the deorbit burn, how the nose cone performed, how the deorbit was executed, and then the entry was phenomenal.”

Weeks of data reviews are ahead for NASA and SpaceX engineers to analyze the results of the Crew Dragon test flight in more detail.

“This mission was only six days long, ” Stich said. “It was a sprint from start to finish.”

SpaceX will refurbish the Crew Dragon capsule that returned to Earth on Friday for an in-flight abort test scheduled for June. The abort system trial will verify the Crew Dragon’s eight SuperDraco thrusters can safely push the capsule away from an exploding launcher in flight, using a modified Falcon 9 booster to reach a supersonic speed in the stratosphere before triggering the escape maneuver.

Meanwhile, workers at SpaceX headquarters in Hawthorne, California, continue assembly of the Crew Dragon spacecraft for the test flight with astronauts.

SpaceX’s first Crew Dragon spacecraft slated to fly with astronauts on the Demo-2 mission is being assembled and tested at the company’s headquarters in Hawthorne, California. This image of the capsule was taken in August 2018. Credit: Stephen Clark/Spaceflight Now

Assuming the data reviews, the high-altitude abort test, and unresolved technical issues are completed in the coming months, Behnken and Hurley could strap into the next Crew Dragon spacecraft as soon as July, according to the most recent schedule officially published by NASA.

In their comments this week during the Crew Dragon’s test flight, NASA and SpaceX officials did not commit to the July timetable for the demonstration launch with astronauts. But top managers, including NASA Administrator Jim Bridenstine, said they were confident one of the commercial capsules developed by SpaceX and Boeing will be ready for a human spaceflight before the end of this year.

“One of the things that we’re very excited about from this DM-1 mission, is that for the first time we’ve gotten to see an end-to-end test,” said Mike Hopkins, an astronaut assigned to the Crew Dragon’s third space mission, the second with astronauts on-board. “So now we’ve brought together the people, the hardware, and all the processes and procedures, and gotten to see how they all work together, and that’s very important as we move toward putting people on-board the vehicle.”

“We’re very interested in seeing the data,” Hopkins said Friday. “I suspect there’s going to be be some lessons learned, some improvements, some changes that we’re going to have to make from this. That’s all part of the testing process.”

NASA says SpaceX still must complete further testing of the Crew Dragon’s parachutes before astronauts can ride the spacecraft. Engineers may need to install heaters in propellant lines leading to the capsule’s Draco thrusters to address a concern that cold fuel could cause a shock, damaging the control jets.

SpaceX kept the hydrazine and nitrogen tetroxide propellants warm on the unpiloted test flight my pointing certain parts of the spacecraft toward the sun. NASA will likely desire a more permanent solution before astronauts get the green light to fly.

Engineers are also still studying the safety of carbon overwrapped pressure vessels inside the Falcon 9 rocket and the Crew Dragon spacecraft, officials said before last week’s launch.

The vessels on the Falcon 9 rocket contain helium to pressurize the launcher’s propellant tanks. SpaceX began flying a resigned helium reservoir last year with fixes to avoid a problem that led to friction in the fibers on the outside of one of the vessels, causing a spark inside an oxygen tank that destroyed a Falcon 9 rocket and a commercial communications satellite during a pre-launch test in 2016.

“We’re very interested in seeing the data,” Hopkins said Friday. “I suspect there’s going to be be some lessons learned, some improvements, some changes that we’re going to have to make from this. That’s all part of the testing process.”

Boeing’s CST-100 Starliner crew capsule, which is also primarily funded through a multibillion-dollar NASA contract, is scheduled to lift off on a United Launch Alliance Atlas 5 rocket later this year for an unpiloted test flight to the space station, similar to the mission just concluded by SpaceX.

The most recent schedule released by NASA indicates the first Starliner test flight could launch as soon as April. However, that is widely expected to be delayed until some time this summer, at the earliest, as Boeing engineers contend with their own technical issues.

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