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Boeing Starliner Lands at White Sands After Clock Error Prompts Early Return Boeing Starliner Lands in New Mexico After Clock Error Prompts Early Return
(about 3 hours later)
Boeing’s new spacecraft, the CST-100 Starliner, safely parachuted to Earth on Sunday, landing atop inflated airbags before dawn at the White Sands Missile Range in New Mexico.Boeing’s new spacecraft, the CST-100 Starliner, safely parachuted to Earth on Sunday, landing atop inflated airbags before dawn at the White Sands Missile Range in New Mexico.
The capsule’s safe return put a less unhappy ending to the mission, which was able to complete many but not all of its objectives. The mission was an important step in NASA’s efforts to resume human spaceflight from the United States. Agency officials said it was too early to decide whether the next flight of Starliner will include astronauts on board as currently planned. “It was an absolute bull’s-eye,” said Jim Bridenstine, the NASA administrator during a news conference after the landing.
The mission’s earlier mishap added to a week of bad news for Boeing, which announced its commercial plane division would temporarily halt production of the 737 Max, its most popular passenger jet, which crashed in 2018 and 2019 and was subsequently grounded. The safe and seemingly flawless return of the capsule, which did not have any people aboard, provided an upbeat ending to a mission that started unhappily when a clock problem caused the spacecraft to deplete its propellant. A planned docking at the International Space Station was called off, and the capsule returned after only two days in orbit.
The capsule, which was built to resume launches of astronauts from the United States, was forced to end its crewless test flight early because a problem with its internal clock right after launch on Friday put it into the wrong orbit. That led to unexpected firing of the maneuvering thrusters, which depleted propellant and precluded the possibility of docking with the International Space Station. “Make no mistake,” Mr. Bridenstine said. “This did not go according to plan in every way we would have hoped. But it is also true that we got a lot of really good information so that we can keep making meaningful progress.”
About half an hour before landing, it fired thrusters for 55 seconds to drop out of orbit. That set off an automated choreography — jettisoning pieces no longer needed, deploying parachutes, inflating the airbags — to precisely aim at the landing site. The mishap on Friday added to a week of bad news for Boeing, which announced its commercial plane division would temporarily halt production of the 737 Max, its most popular passenger jet, which crashed in 2018 and 2019 and was subsequently grounded.
Quite simply: Starliner got the time wrong. How the shortened flight affects the Starliner schedule and NASA’s plans to resume launching of astronauts on American rockets from American soil is not yet known.
When the spacecraft separated from the Atlas 5 rocket that lifted it to space, an incorrect clock caused it to start firing its thrusters and try to get into the position and orientation where it thought it should be. Diagnosing and fixing the clock problem could add delays to the commercial crew program, NASA’s strategy of relying on private companies to build spacecraft to carry astronauts to and from the space station. It is already more than two years behind its original timeline.
“She thought she was later in the mission,” Jim Chilton, senior vice president of the space and launch division at Boeing, said during a news conference on Saturday, “and being autonomous, started to behave that way.” Jim Chilton, senior vice president of the space and launch division at Boeing, estimated that the mission obtained enough data to fulfill 85 to 90 percent of the test objectives.
That caused it to use much more propellant than was expected. Its communications antennas also were not pointed in the correct position, which meant it did not immediately receive corrective commands from Boeing’s flight controllers on Earth. Because of the initial problem, not enough propellant remained to rendezvous and dock with the space station. “The vessel looks great,” Mr. Chilton said. “They’re telling us there’s hardly any charring, perfectly level on her airbags. And that bodes really well for reusability.”
“If I knew, it wouldn’t have happened” Mr. Chilton said. “We were surprised.” The Starliner capsule will be transported back to Kennedy Space Center in Florida, where it will be refurbished. Each capsule is designed to fly up to 10 times, and this one is currently scheduled to head to space again, this time with astronauts, in the second half of 2020.
The spacecraft’s software set its clock based on the time it received from the Atlas 5 rocket before launch, and it is still too early to tell how it pulled the incorrect information, said Mr. Chilton. He added that the problem was with the Boeing software, not with the rocket, which was built by the United Launch Alliance. Before then, Boeing is to fly another test flight, but with astronauts aboard.
This flight did not have anyone on board, but NASA and Boeing officials insist that if astronauts had been in the capsule, they would have been safe. The astronauts might even have been able to take over manual control and send the spacecraft on the proper path. Steve Stich, deputy manager of the commercial crew program for NASA, said teams from the agency and Boeing will spend weeks analyzing the data.
Flight controllers were able to send Starliner the correct time. They then performed a couple of thruster firings to raise its orbit to a circular one 155 miles above the surface. That is lower than the International Space Station, which is at an altitude of about 250 miles. “To me, there’s good data out there that suggests that once we go through it, maybe it’s acceptable to go, next step, fly the crewed flight test,” Mr. Stich said. “But we have to go through the data first.”
Mr. Chilton said the spacecraft’s propulsion, navigation and life support systems operatied well. Mr. Chilton agreed that it was too early to say whether the next Starliner flight will have astronauts aboard. “We’re not in position to propose that and we don’t propose it until we know the machine is worthy,” he said.
Boeing and NASA will investigate what went wrong and fix it. About half an hour before landing, thrusters fired for 55 seconds to drop the spacecraft out of orbit. That set off an automated choreography — jettisoning pieces no longer needed, deploying parachutes, inflating the airbags — that appeared to unfold flawlessly. The capsule touched down in the freezing desert before sunrise near a former space shuttle runway.
Although the current mission could not perform all of its tasks, the two portions of greatest danger to astronauts — launch and return to Earth — have now been demonstrated. “It was just picture perfect,” Sunita Williams, the NASA astronaut who is to be the commander of the next flight of this capsule. She was at White Sands as part of the team examining the capsule after landing.
At the invitation of Boeing, Ms. Williams said she would like to name the spacecraft Calypso after the ship used by Jacques Cousteau to explore the oceans.
The return of the capsule on land was unusual, at least for NASA. All previous landings of its capsules — the Mercury, Gemini and Apollo programs of the 1960s and 1970s — were in the ocean. After all, you might be safer diving into water than an expanse of sand.The return of the capsule on land was unusual, at least for NASA. All previous landings of its capsules — the Mercury, Gemini and Apollo programs of the 1960s and 1970s — were in the ocean. After all, you might be safer diving into water than an expanse of sand.
But Russian astronauts have always landed on solid ground, and that approach offers advantages. Salt water corrodes metal, which would complicate plans to reuse Starliner capsules for future missions. Also, a capsule hitting an ocean wave at the wrong angle could sink. (That is what happened during testing of Apollo capsules, requiring a revamping of the design.)But Russian astronauts have always landed on solid ground, and that approach offers advantages. Salt water corrodes metal, which would complicate plans to reuse Starliner capsules for future missions. Also, a capsule hitting an ocean wave at the wrong angle could sink. (That is what happened during testing of Apollo capsules, requiring a revamping of the design.)
The returned Starliner capsule is expected to be used again for a future mission carrying astronauts. While NASA and Boeing had many reasons to celebrate on Sunday, the mission went awry in a puzzling way on Friday. Quite simply, Starliner got the time wrong.
NASA still hopes to carry astronauts to orbit again in the first half of 2020, and has hired two companies to take astronauts to the space station, Boeing and SpaceX. Both have encountered hurdles and delays. When the spacecraft separated from the Atlas 5 rocket that lifted it to space, an incorrect clock, off by 11 hours, caused it to start firing its thrusters and try to get into the position and orientation where it thought it should be.
The problem with Boeing’s Starliner does not directly affect SpaceX’s Crew Dragon capsule. But that company still has to complete tests of its parachute and conduct an in-flight test of its abort system, currently scheduled for Jan. 11, before it is ready to carry astronauts. “She thought she was later in the mission,” Mr. Chilton said on Saturday, “and being autonomous, started to behave that way.”
Boeing had been aiming for a demonstration flight taking astronauts to the space station in the first half of 2020. But the problems on Friday’s uncrewed test may lead to further delays. Boeing does not know what went wrong.
“If I knew, it wouldn’t have happened” Mr. Chilton said. “We were surprised.”
The spacecraft’s software set its clock based on the time it received from the Atlas 5 rocket before launch, and it is still too early to tell how it pulled the incorrect information, said Mr. Chilton. He added that the problem was with the Boeing software, not with the rocket, which was built and operated by another company, the United Launch Alliance.
This flight did not have anyone on board, but NASA and Boeing officials insist that if astronauts had been in the capsule, they would have been safe. The astronauts might even have been able to take over manual control and send the spacecraft on the proper path.
Flight controllers were eventually able to send Starliner the correct time. They then performed a couple of thruster firings to raise its orbit to a circular one 155 miles above the surface. That was lower than the International Space Station, which is at an altitude of about 250 miles.
During its abbreviated time in orbit, the spacecraft’s propulsion, navigation and life support systems appeared to work well. Even though the Starliner did not go to the space station, flight controllers were able to test some of the systems needed to the rendezvous. That included establishing a communication link between the spacecraft and station and extending, then retracting a ring that would have attached to the docking port.
The two portions of the mission of greatest danger to astronauts — launch and return to Earth — have been demonstrated.
NASA still hopes to carry astronauts to orbit again in the first half of 2020, and has also hired another company, SpaceX, to take crews to the space station.
The problem with Boeing’s Starliner does not directly affect SpaceX’s capsule, Crew Dragon, which completed its first trip to and from the space station in March. But SpaceX has encountered its own hurdles and delays, and still has to complete tests of its parachute and conduct an in-flight test of its abort system, before it is ready to carry astronauts. That launch is currently scheduled for Jan. 11.
NASA has already talked to Russia about buying additional seats on the Soyuz rockets, which have been the only transportation available to astronauts to and from the International Space Station since 2011.NASA has already talked to Russia about buying additional seats on the Soyuz rockets, which have been the only transportation available to astronauts to and from the International Space Station since 2011.