THE launch of Boeing's new $1.5billion Starliner spacecraft has once again been sensationally called off just moments before takeoff.
The inaugural flight was abruptly halted on Saturday despite having the two astronauts ready to go and strapped into their seats with the mission now postponed for at least 24 hours.
The CST-200 Starliner's voyage up to the International Space Station (ISS) has been delayed once again as Boeing claims a "tech issue" has plagued the big day.
An automatic hold triggered by the computer that launches the rocket stopped the countdown clock, say reports.
Two NASA astronauts, Suni Williams and Barry Wilmore were said to have been strapped into the capsule awaiting liftoff at Cape Canaveral, Florida.
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But the countdown was dramatically halted with just three minutes and 50 seconds left on the clock.
Commander Barry “Butch” Wilmore, 61, is a retired Navy captain who's clocked some 178 days in space during his life already.
Fellow pilot Suni Williams, 58, a former Naval test pilot also has experience flying over 30 different aircraft.
She has spent a whopping 322 days in space in her two missions since her first flight in 2007.
They were due to spend around a week in the ISS.
Both have now left the capsule and returned to the headquarters to get some clarity on the blunder.
The postponement was announced during a live NASA webcast.
The next available launch opportunities are on Sunday (June 2) Wednesday (June 5) and Thursday (June 6).
The launch has previously been delayed over leak checks and rocket repairs.
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The first attempt in 2019 failed due to software and engineering glitches despite the craft being unmanned.
A second attempt in 2022 was successful however and led to a new test that would see a pair of astronauts in the cockpit.
But, on May 6, the countdown was again stopped early at just two hours before launch over a faulty pressure valve on the Atlas upper stage.
These launch dates are not magical. They are an opportunity to do our job. There will be more issues, and we'll be ready to handle them
Suni Williams
Williams has previously labelled spaceflight "complicated".
She recently said: "Every step of the way, we're realizing this makes us rethink how we do business.
"We have a capable spacecraft and we have people that can find solutions. We expect to find things that will help us make the spacecraft safer to fly.
"These launch dates are not magical. They are an opportunity to do our job. There will be more issues, and we'll be ready to handle them."
It was set to blastoff from NASA's Kennedy Space Center in Florida on top of an Atlas V rocket.
The capsule will go through a 26-hour flight before docking at the ISS at around 250 miles above Earth.
The two astronauts will stay at the space station before coming back to Earth in the Starliner before using a parachute and airbag-assisted landing platform.
The seemingly doomed craft has been made by United Launch Alliance - a Boeing-Lockheed Martin joint venture.
Starliner was created in collaboration with NASA’s Commercial Crew Programme, which is similar to its now-defunct Shuttle programme.
It's aimed at making space flights commercially available, frequently ferrying people and cargo back and forth from Earth.
“For Nasa service missions to the International Space Station, it will carry up to four Nasa-sponsored crew members and time-critical scientific research,” Boeing said.
With Boeing hoping the spacecraft can eventually transport humans to Mars if it ever gets off the ground.
Aerospace giants Boeing have 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.
