Boeing's Starliner first test flight was in 2019, but that did not end well, so the company is trying for the second time to launch it this summer. However, a series of unfortunate events have prevented the launch as well.

The Starliner was supposed to launch to the International Space Station (ISS) from Cape Canaveral Space Force Station in Florida on July 30. This mission was dubbed as the Orbital Flight Test 2 (OFT-2). But it was delayed due to unplanned thruster firings of Russia's Nauka module.

Both NASA and Boeing decided to delay the launch last week to give the crew enough time to assess the Nauka docking mishap. They rescheduled it for Tuesday, August 3. But another unfortunate event occurred that even moving the launch schedule the following day is not possible. The astronaut taxi will have to wait to launch to the space station.

(Photo: Getty Images)
CAPE CANAVERAL, FL - JULY 29: In this NASA handout, A United Launch Alliance Atlas V rocket with Boeings CST-100 Starliner spacecraft onboard is seen as it is rolled out of the Vertical Integration Facility to the launch pad at Space Launch Complex 41 ahead of the Orbital Flight Test-2 (OFT-2) mission, Thursday, July 29, 2021 at Cape Canaveral Space Force Station in Florida. Boeings Orbital Flight Test-2 will be Starliners second uncrewed flight test and will dock to the International Space Station as part of NASA's Commercial Crew Program. The mission, currently targeted for launch at 2:53 p.m. EDT Friday, July 30, will serve as an end-to-end test of the system's capabilities. Photo Credit: (NASA/Joel Kowsky)

Starliner Launch Delayed Due to Unexpected Issues in Its Propulsion System

Boeing announced on August 3 on their website that its Starliner OFT-2 mission launch will be postponed due to unexpected errors with the spacecraft's propulsion system.

"We're disappointed with today's outcome and the need to reschedule our Starliner launch," Boeing's Commercial Crew Program vice president and program manager John Vollmer said.

"Human spaceflight is a complex, precise, and unforgiving endeavor, and Boeing and NASA teams will take the time they need to ensure the safety and integrity of the spacecraft and the achievement of our mission objectives," he added.

Engineers doing the pre-launch preparations of the uncrewed CST-100 Starliner spacecraft detected unexpected valve position indications in the propulsion system, Boeing said.

As a result, Starlink's launch aboard a United Launch Alliance Atlas V rocket is delayed, and the Boeing team will continue to provide updates regarding its future launch.

According to Space.com, NASA already confirmed the cause and delay of Starlink's launch. They added that the space taxi might get to launch the next day depending on the resolution of the problem.

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Starliner Launch Delayed Indefinitely

Despite the optimism they displayed at the initial announcement of Starliner's launch delay on Tuesday, NASA and Boeing announced later that night at 6 p.m. ET that the spacecraft will be rolled back from the launch site to the Vertical Integration Facility. They have not yet announced the next available launch window, which means that the OFT-2 launch mission will be delayed indefinitely.

Vollmer said in a released statement that their team is working diligently to ensure the safety and success of the mission. So, they had to delay the launch until the vehicle is performing at a level on which their crew is confident that it is ready to fly.

This will be the second time the CST-100 Starliner and ULA's Atlas V were rolled back from the launch site and into the assembly facility. The first one was on July 30 to protect the duo from the unpleasantly cold weather.

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Check out more news and information on Boeing Starliner in Science Times.