ABC News August 3, 2021

Boeing Starliner's 2nd launch attempt delayed again

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Boeing's chance at redemption for its Starliner spacecraft will have to wait for now. The launch attempt scheduled for Tuesday was scrubbed at the last minute, NASA said.

The attempt was scrubbed "due to unexpected valve position indications in the Starliner propulsion system," NASA noted. Further details were not immediately available, but the space agency said the next launch opportunity is 12:57 p.m. ET on Wednesday.

The second test flight for Boeing's CST-100 Starliner spacecraft was scheduled to launch from the Florida coast on Tuesday afternoon before it was called off. This comes on the heels of last week's launch attempt also being scrubbed due to an unplanned thruster-firing incident on the International Space Station.

The first Starliner launch in December 2019 famously did not go as planned and the spacecraft never reached the ISS.

NASA via Getty Images
A United Launch Alliance Atlas V rocket with Boeings CST-100 Starliner spacecraft at Space Launch Complex 41, Aug. 2, 2021 at Cape Canaveral Space Force Station in Florida.

NASA was set to carry live coverage of the uncrewed mission starting at 12:30 p.m. ET Tuesday. It's part of NASA's Commercial Crew program, in which the space agency tapped the private sector to help with missions in low-Earth orbit. It's not immediately clear when the next launch opportunity will be.

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On Monday, the Starliner spacecraft and a United Launch Alliance Atlas V rocket were rolled out on to the launch pad at Florida's Cape Canaveral Space Force Station ahead of Tuesday's liftoff. Meteorologists with the U.S. Space Force 45th Weather Squadron predicted a 60% chance of favorable weather for launch day.

After launching, the Starliner was supposed to commence a daylong trip to the space station.

The spaceship was set to bring some 400 pounds of cargo and supplies to the space station crew.

While the test flight is uncrewed, an anthropometric dummy dubbed "Rosie the Rocketeer" will be aboard the Starliner when it launches.The 180-pound test device will sit in the commander's seat of the capsule for the test flight, and its sensors will be used to collect data on how the launch will impact eventual human passengers. The model human was named after the World War II icon Rosie the Riveter, and is meant to honor women pioneers in aerospace. The test device is clad in the iconic red polka-dot bandana.

Boeing also said it will be paying tribute to more than a dozen historically Black colleges and universities during the upcoming flight test. Among the cargo inside the spacecraft are flags, small pennants and other items "representing HBCUs from throughout the U.S.," according to a statement from the company.

NASA and Boeing blamed errors in automation and software issues for the botched launch in December 2019, saying mission clocks were not in sync and thus timing errors prevented the Starliner from reaching the orbit it needed in order to get to the space station. Rather than reach the space station, the Starliner landed in White Sands, New Mexico.

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The second test flight mission is seen as critical for Boeing, as it has yet to launch astronauts for NASA while its Commercial Crew program competitor SpaceX has flown multiple crewed missions to the space station in addition to numerous cargo flights. Boeing is also still reeling from the fallout related to issues with its 737 Max jets. If the Starliner launch fails again, it is difficult to see how it will be able to remain competitive against SpaceX for NASA contracts -- especially as the private sector's involvement in the budding commercial space industry has grown significantly over the past year.