BOEING is poised to finally get its shot at space stardom today as the company's long-delayed mission prepares to take off.
Starliner has been marred by setbacks and its most recent attempt was cancelled mere hours before launch due to a safety concern.
That issue has been resolved but engineers have since found a helium leak.
After further investigation it was decided that the mission can go-ahead regardless.
“We can handle this particular leak if that leak rate were to grow even up to 100 times,” said Steve Stich, manager of Nasa’s Commercial Crew Program, according to AFP.
Two Nasa astronauts will take a ride on Starliner towards the International Space Station (ISS).
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They include Commander Barry “Butch” Wilmore, 61, a retired Navy captain who's clocked some 178 days in space since his first of two space missions in 2009.
He'll be joined by pilot Suni Williams, 58, a former Naval test pilot with experience flying over 30 different aircraft and 322 days under her belt spent in space over two missions since her first flight in 2007.
They will spend about a week in the ISS.
But Boeing hopes the spacecraft will eventually transport humans to Mars.
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The aerospace giant has long been involved in Nasa's human spacecraft program, receiving more than $4billion to develop and fly the Starliner in 2014.
Boeing is competing with the likes of SpaceX to provide gear for future Nasa missions and has spent nearly $600million fixing engineering setbacks from the past mishaps.
Starliner is expected to take off from Cape Canaveral Space Force Station in Florida at 12:25pm ET / 17.25pm BST.
If there's another reason to abort, there are other launch opportunities are available on Sunday (June 2) Wednesday (June 5) and Thursday (June 6).
Here we go again...
Analysis by Jamie Harris, Senior Technology and Science Reporter at The Sun
Boeing really hasn't had much luck with its first crewed space launch but it looks like they may finally have some good news.
The company attempted to send an uncrewed Starliner to the ISS in 2019 but it failed because of a bunch of issues - not to mention disruption caused by the pandemic - and came back to Earth early.
A second uncrewed test went ahead in 2022 just fine but a year later experts uncovered new problems which held up a launch carrying astronauts.
Of course, safety is first so it's a necessary step.
Experts working on the billion dollar project have attempted to downplay the delay.
"I don't call it frustrating at all," Boeing's program manager Mark Nappi recently told press.
"We would like to have been further along at this time. There's no doubt about that. But we're here, and we're prepared, and we're ready to fly."
Space is also costly business, so Boeing - and Nasa - need this mission to succeed.
Development woes cost the firm a whooping $1.5billion in charges, as well as roughly $325million for Nasa in boosts to Boeing's $4.2billion fixed-price Starliner contract, according to securities filings and contracting data examined by Reuters.
Nasa also needs this to work if it's to keep up with China which is making huge advances to the Moon and beyond.