NASA: Boeing’s Starliner test flight to ISS can continue on May 19 – update

NASA and Boeing say they are confident in Boeing’s solution to the earlier problem with valves in the Starliner capsule’s propulsion system. That means that the previously postponed test flight can continue on May 19.

Steve Stich, NASA’s Commercial Crew Program Manager, said in a statement that it’s been a “difficult eight months, but it’s very satisfying that we’ve solved the problem with the oxidizer isolation valves.” writes Space.com. He says the launch can go ahead. This was scheduled for May 19.

The solution consists of several parts. Among other things, engineers sealed off “a potential moisture path” in the electrical connectors of the valves. Also, moisture is kept out of the valves with nitrogen gas and the oxidizer dinitrogen tetraoxide is charged later.

This oxidizer turned out to be the culprit. 13 of the 24 valves remained stuck in the closed position. This was because the agent leaked through a valve and reacted with moisture there, creating nitric acid. That in turn reacted with the aluminum of the valve housings, leading to corrosion.

These issues have resulted in a long delay. The so-called Orbital Flight Test 2 with Boeing’s Starliner capsule should have gone up as early as July 30, 2021, but that was postponed more than once and eventually indefinitely when the problems came to light.

The name Orbital Flight Test 2 makes it clear that there has also been a first flight. This launch and flight took place in December 2019. The Starliner capsule failed to reach the International Space Station because it entered a wrong orbit. The reason for this was not properly synchronized clocks of the capsule, which caused the engines to burn for too long.

Like SpaceX’s Crew Dragon, the Starliner capsule is part of NASA’s Commercial Crew Program. This is a program in which Boeing and SpaceX can each transport astronauts to the ISS with their own capsule. Boeing wants to do that with Atlas V rockets and SpaceX uses its Falcon 9 rockets for that.

SpaceX is way ahead of Boeing in this program. Elon Musk’s company has already brought the necessary astronauts to the ISS with the Crew Dragon capsule, while Boeing must first demonstrate with the Orbital Flight Test 2 that it can successfully conduct an unmanned flight to the ISS.

Update 13:13 o’clock: Boeing lets you know that transportation of the Starliner pod to the launch complex has been paused due to a hydraulic leak at the United Launch Alliance transport vehicle. That is a joint venture between Lockheed and Boeing and is the company behind the Atlas V rocket with which Starliner should eventually reach the ISS. It is still unknown what this means for the May 19 launch. Boeing says a maintenance team is on its way to review the situation.

The Starliner capsule as it was transported Tuesday toward the launch complex Boeing’s Starliner capsule atop the Atlas V rocket in the run-up to the ultimately canceled Orbital Flight Test 2