Boeing’s second chance at a do-over is off to a successful start as Starliner, its space taxi, launched to orbit on Thursday.
The spacecraft was built for NASA to take astronauts to and from the International Space Station. But before it can do that, it has to complete a test flight without astronauts to show that its systems all work properly.
Two previous attempts to undertake that preparatory journey — the first in December 2019 and the second in August 2021 — were both marred by serious technical problems. The setbacks have also cost Boeing hundreds of millions of dollars.
Boeing is catching up to SpaceX, the newer space company founded by Elon Musk that has already carried five NASA crews to orbit in the past two years.
A second transportation option for NASA also offers resilience in case either spacecraft suffers an accident.
Otherwise, NASA would have to rely again on Russia’s Soyuz capsules, which were the only ride to orbit for American astronauts for nearly a decade. Collaboration between the United States and Russia on the space station has become politically complicated after Russia invaded Ukraine earlier this year.
At 6:54 p.m. Eastern time, the engines of an Atlas 5 rocket roared from a launching pad at Cape Canaveral Space Force Station in Florida, lifting Starliner toward the sky. Thirty-two minutes later, it was safely in orbit.
Just over 24 hours after launch, Starliner is scheduled to dock at the International Space Station.
After four or five days attached to the space station, Starliner is to return to Earth, at one of five locations in the western United States. While most American astronaut capsules have splashed down in the ocean — including SpaceX’s Crew Dragon — Starliner parachutes onto land and sets down atop airbags.
If all goes well, the flight will provide NASA with sufficient data to certify that the spacecraft can safely carry people into space. A demonstration flight with two or three astronauts aboard could launch as soon as the end of the year.
Although this mission is not carrying any astronauts, one of Starliner’s seats is filled by a mannequin named Rosie the Rocketeer.
There is also more than 800 pounds of cargo aboard, mostly food and supplies for the space station crew, but also some memorabilia. The spacecraft is to bring back to Earth almost 600 pounds of cargo from the space station.
Thursday’s launch was a relief for Boeing and NASA officials. The countdown and entry to orbit unfolded without unexpected troubles.
In an uncrewed Starliner flight in December 2019, the problems started almost immediately upon reaching orbit.
A software error caused the Starliner’s clock to be set to the wrong time. That caused the onboard computer to try to move the spacecraft to where it thought the vessel should be. The firing of the thrusters used up much of the propellant, and plans for Starliner to dock at the space station were called off.
While troubleshooting that problem, Boeing engineers discovered a second flaw that would have caused the wrong thrusters to fire as the capsule prepared for re-entry, potentially leading to the destruction of the spacecraft. They fixed that software flaw while Starliner orbited the Earth, and the capsule landed safely at White Sands, N.M.
Those problems put a hold on what would have been the next step: a demonstration flight with astronauts aboard. NASA told Boeing that it needed to repeat the uncrewed test flight, at Boeing’s cost.
Boeing spent more than a year revamping and retesting the software, and in August last year, Starliner was back at the launching pad at Cape Canaveral Space Force Station in Florida, on top of a second Atlas 5 rocket.
The countdown started, but had to be halted. Flight managers discovered that 13 valves in Starliner’s propulsion system had failed to open.
Boeing then spent about eight months investigating the corrosion that had caused the valves to stick shut. Boeing swapped out the service module — the piece of Starliner below the capsule that houses the propulsion system — with one that had been planned for the next mission.
NASA hired two companies to take astronauts to and from the station: SpaceX and Boeing. At the time of Boeing’s test flight in 2019, it seemed that Starliner would beat out SpaceX’s Crew Dragon capsule for the first mission with astronauts.
But with Starliner remaining on the ground, SpaceX has since launched seven Crew Dragon missions with astronauts. In addition to the five missions for NASA, two others carried private citizens to orbit.
SpaceX’s missions also appear to be significantly less expensive than Boeing’s. Still, NASA officials say that they are committed to Starliner and that having two systems provides competition, innovation and flexibility.
Soruce : https://www.nytimes.com/2022/05/19/science/nasa-boeing-starliner-launch.html