Watch live: Relativity Space lines up night launch for its 3rd try to send up 3D-printed rocket

Could the third time be the charm for the first-ever launch of Relativity Space’s 3D-printed Terran 1 rocket?

That’s the plan for the Long Beach, California-based startup company with its mission dubbed “GLHF,” as in “Good Luck, Have Fun” with a liftoff during a three-hour window that begins at 10 p.m. Wednesday and runs until 1 a.m. Thursday from Cape Canaveral Space Force Station’s Launch Complex 16.

The company said late Wednesday it was keeping the countdown clock at T-45 minutes so no launch would occur until at least 10:45 p.m. citing strong upper level winds. But the latest weather balloon data was trending positively the company stated, so it would continue the delayed start of the live stream coverage at 10 p.m. for the attempt on its YouTube channel.

“Today, I’m incredibly proud of our team and all the people that believed in me against all odds to get here,” company cofounder and CEO Tim Ellis posted to Twitter. “I get asked all the time how I’m feeling - proud, and surreal! It’s an intense feeling stepping up to the global stage on the eve of our first launch. But we are ready!!!”

Weather is looking good for the attempt with Space Launch Delta 45′s weather squadron giving a 95% chance for good conditions. Propellant load began this evening as the countdown to the opening of the window approaches.

It hasn’t been the weather, though, that forced two earlier launch attempts to scrub.

The most recent on March 11 was due to “an automated abort on stage 2 fuel pressure, which was only one PSI low,” according to post-scrub details posted to the company’s Twitter page.

The first attempt on March 8 had liquid oxygen above the required temperature on its upper stage.

Still, the GLHF mission looks to accomplish a series of firsts including sending what would become the largest 3D-printed object flown into space. The Terran 1 is 85% 3D-printed including its engines.

It could also become the first rocket to use the a fuel dubbed “methalox,” which is liquid oxygen and refined liquid natural gas close to methane. The mixture is thought to be the future for rocketry as it would be an easier fuel to deal with in space for refueling. SpaceX’s new Starship, ULA’s upcoming Vulcan and Blue Origin’s in-development New Glenn also will use the mixture. China has also tried, but failed, to send up a rocket using this next-generation fuel.

If Terran 1 was able to achieve orbit on its first try, that would also be a first. Companies like SpaceX, Astra Space, Firefly and others have all taken several tries before reaching orbit successfully.

The Terran 1 rocket is smaller compared with SpaceX’s Falcon 9 or ULA’s Atlas rockets, standing at just 110 feet tall. The first stage uses nine Aeon 1 engines with the second stage using a single Aeon vacuum engine. It’s capable of sending 2,756 pounds of payload to low-Earth orbit of about 310 miles, but this test flight is only aiming to hit between 125-130 miles high.

There is no customer for this first test flight, which the company has said is acting mostly as a “pathfinder” to pave the way for a larger rocket called Terran R. Terran R aims to be 95% 3D-printed and feature a reusable first stage that could compete with the likes of SpaceX and ULA.

GLHF will fly up a symbolic 3D-printed metal object that was one of the company’s first-ever 3D-printed items.

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