The Boeing CST-100 Starliner spacecraft is secured atop a United Launch Alliance Atlas V rocket at the Vertical Integration Facility at Space Launch Complex-41 at Cape Canaveral Space Force Station in Florida on July 17, 2021. Starliner will launch on the Atlas V for Boeing’s second Orbital Flight Test (OFT-2) for NASA’s Commercial Crew Program. The spacecraft rolled out from Boeing’s Commercial Crew and Cargo Processing Facility at NASA’s Kennedy Space Center earlier in the day. (Boeing/Boeing)

A new crew-worthy spacecraft could be docking with the International Space Station in just over a week as NASA and Boeing gave the CST-100 Starliner the OK to launch from the Space Coast.

In a flight readiness review, teams signed off on sending the Commercial Crew Program capsule on its redo attempt to dock with the ISS targeting a liftoff on Thursday, May 19 at 6:54 p.m. EDT atop a United Launch Alliance Atlas V rocket from Cape Canaveral Space Force Station’s Space Launch Complex-41.

“The point of this demonstration is to make sure that we’re buying down risks and thoroughly testing out the system before we go put crew on the next vehicle,” said NASA’s Kathryn Lueders, associate administrator for the Space Operations Mission Directorate.

NASA officials will reconvene on Tuesday, and if weather cooperates, the rocket and spacecraft are slated to roll to the pad on Wednesday.

This rendering shows the Boeing CST-100 Starliner capsule designed to ferry astronauts to and from the International Space Station. (Boeing)

The Orbital Flight Test-2 looks to get Boeing back in the game to join SpaceX and its Crew Dragon as vehicles capable of launching astronauts from U.S. soil to the station. The first OFT took off in December 2019, and made it to orbit and back to Earth, but missed its goal of hooking up with the space station because of a series of software and other issues that at the time NASA labeled as a “high visibility close call.”

That misstep led to a recommendation of 80 changes that spanned hardware, software and operations, all of which had been addressed ahead of an attempt to launch OFT-2 last August. But that attempt went awry when a new issue popped up — valves getting stuck in the wrong position on the service module propulsion system.

Despite efforts to fix the valves on the launch pad, Boeing was forced to roll Starliner back to its factory at Kennedy Space Center, after which it spent months diagnosing the culprit — corrosion caused by excess moisture that led to the sticky valves.

Despite the valves having worked fine on both the previous OFT launch as well as other tests, Boeing opted to just switch out service modules and introduce some workarounds to mitigate the chance of it happening again.

Now eight months since the last attempt, Starliner looks to finally get its uncrewed flight off the ground again. The goal is to dock with the space station one day after launch on May 20 to demonstrate its ability to safely transport humans to and from the station.

Parts of the OFT-2 mission that were not able to be performed the first time around include the docking and undocking with the ISS using a never-before-used rendezvous sensor package. Mission managers will also be able to monitor the emergency abort system on launch, something that was not in place for OFT-1.

Teams will once again see how the vehicle’s thermal shield holds up, how the atmosphere is exchanged while docked with the ISS and make sure that ISS crew can synch data with Starliner.

The capsule is basically ready to fly with humans but is still bringing along stand-in mannequin named Rosie the Rocketeer.

It will stay docked for five days or more before returning to Earth for a ground landing in the western U.S., unlike SpaceX’s water landings off the Florida coast in its Crew Dragons.

If successful, a crewed test launch could happen before the end of the year paving the way for regular contracted service flights to the station.

“We will learn a lot I think on this test flight,” said NASA’s Commercial Crew Program manager Steve Stich. “Really the only way to get the final piece of data you need to fly crew is to go fly the vehicle in an environment that includes flying during the ascent on orbit and then docking in proximity to ISS, and we’re about to go do that.”

NASA officials said the plan is to have Boeing and SpaceX trade off each year with one expedition flight each, although both Starliner and Crew Dragon crafts could also be visiting outside of the Commercial Crew Program such as the Axiom Space mission AX-1 that left the ISS last month.

Both Boeing and SpaceX had seen delays leading up to their test launches, but SpaceX was able to forge ahead finally sending up its Demo-2 flight with NASA astronauts Bob Behnken and Doug Hurley in May 2020, marking the first time humans had flown to the ISS from U.S. soil since the end of the space shuttle program nearly a decade earlier.

Since Space Shuttle Atlantis’ final landing in 2011, NASA had had to rely on Russian Soyuz flights to keep its presence on the station, but seat prices were climbing over the years to a reported $80 a pop.

The contracts to SpaceX and Boeing were originally for six operational flights each to the ISS. SpaceX has already made four of them with Crew-4 docking at the end of April, and is on tap to send up Crew-5 in mid-September.

But now after years of delays, NASA managers are ready for Boeing to join the fleet.

“We’re operational,” Stich said. “We’re getting ready to go fly, and when the weather’s right and the systems are right we’ll go fly the flight.”