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Monday, 22 November 2021

Astra reaches orbit for first time, clearing way for commercial launches

Astra LV0007 Reaches Orbit from Astra on Vimeo.

Astra launched its first rocket into orbit from Alaska early Saturday after falling short on three previous tries, an achievement company officials said will unlock “tremendous demand” for its small satellite launch service.

Company officials did not disclose a scheduled for its next mission in a virtual briefing with reporters Monday. But a NASA official said Astra’s next mission will carry six small CubeSat payloads into orbit for the space agency, and could take off before the end of the year.

Astra’s rocket, designated Rocket 3.3 or LV0007, launched from the Pacific Spaceport Complex on Kodiak Island, Alaska, at 1:16 a.m. EST (0616 GMT) Saturday. Heading south from Kodiak, the 43-foot-tall (13.1-meter), 4.3-foot-wide (1.3-meter) rocket soared high above the Pacific Ocean, then arced downrange to gain speed on the way to orbit.

Liftoff occurred at 9:16 p.m. local time in Alaska, where a lean crew of five Astra engineers and technicians readied the rocket for liftoff in recent weeks.

Five kerosene-fueled Delphin engines, combining to generate 32,500 pounds of sea level thrust, powered the launcher in the first 2 minutes, 50 seconds, of the mission. The first stage jettisoned a few seconds later, followed by separation of the payload shroud on top of the rocket.

A single Aether engine ignited on the second stage to accelerate the rocket to orbital velocity, reaching a speed of more than 17,000 mph (7.61 kilometers per second) at cutoff nearly nine minutes after liftoff.

The test flight delivered a non-separating payload to orbit for the U.S. Space Force, which named the mission STP-27AD2. The Space Force considered the launch a demonstration mission to evaluate Astra’s launch capabilities for future military satellites.

Military tracking data showed the rocket reached an orbit between 272 miles and 315 miles (438-by-507 kilometers) in altitude, with an inclination angle of 86 degrees to the equator.

Benjamin Lyon, Astra’s chief engineer, called it a “phenomenal flight,” adding that the rocket hit its altitude and inclination targets.

“This is a pretty historic milestone for Astra,” said Chris Kemp, Astra’s founder, chairman, and CEO. “Just over five years since we incorporated Astra and started building the facility we’re now in, we were able to learn our way to orbit, as we like to say, launch by launch, increasing the capabilities and operational efficiencies of our system along the way.

“And we’re now focusing on delivering for our customers and scaling up the production and the launch cadence of our system,” Kemp said.

Founded in 2016, Astra designed its rockets to deploy small payloads, pursuing a launch market to deliver CubeSats, nanosatellites, and microsatellites into orbit. With Saturday’s successful flight, Astra reached orbit a little more than five years since its founding, beating the six-year mark from the establishment of SpaceX until its first orbital flight with the Falcon 1 rocket in 2008.

Astra officials have said they eventually hope to launch daily, tapping demand from the U.S. military, commercial companies, and scientific institutions to rapidly deploy new space capabilities.

To do that, Astra wants to build rockets on an assembly line at its factory in Alameda, California, then ship the vehicles — along with required ground infrastructure — to distant launch sites in standard cargo trailers. A small team with less than a dozen engineers and technicians can set up the rocket and its mobile launch pad at an austere launch site in a few days.

Kemp said the successful launch into orbit proved Astra’s iterative development process, where engineers design, build, and test hardware and software, then rapidly redesign and retest systems if they fail.

“While it is less expensive for one of these smaller vehicles to fail, it still takes time, and time is money,” Kemp said.

Astra’s first orbit-capable rocket, named Rocket 3.0, was supposed to launch in February 2020 in an effort sponsored by the U.S. military’s Defense Advanced Research Projects Agency to demonstrate responsive launch capability. But the mission did not get off the ground before DARPA’s deadline after a series of delays.

Astra intended to try again to launch Rocket 3.0, but the vehicle was destroyed in an accident during a wet dress rehearsal, or fueling test, at Kodiak.

Astra’s first orbital launch attempt Sept. 11, 2020, using Rocket 3.1, ended 30 seconds after takeoff when a guidance system problem caused the rocket to drift off course. In response, the rocket’s engines were commanded to shut down and the vehicle fell back to the spaceport on Kodiak Island.

On Dec. 15, 2020, Astra’s Rocket 3.2 nearly achieved enough speed to enter orbit. But the upper stage engine shut down just seconds before it was supposed to cut off, leaving the rocket just shy of orbital velocity. The vehicle re-entered the atmosphere, and most of it burned up.

Rocket 3.3 debuted several changes to Astra’s design when it launched for the first time Aug. 28.

It’s around 5 feet taller than the rockets Astra used for its first two orbital launch attempts last year. With stretched first stage tanks to hold more propellant, and a lighter second stage, the new rocket configuration can carry heavier cargo into orbit, according to Astra.

Astra also implemented a closed-loop control system on the first Rocket 3.3 mission, also called LV0006, to fix a propellant mixture issue that caused the previous launch last December to fail before seconds before reaching orbit.

The Aug. 28 mission was cut short by the premature shutdown of one of the rocket’s five kerosene-fueled Delphin main engines. The loss of thrust caused the rocket to briefly falter just above the launch pad, then veer sideways before the four remaining engines slowly propelled the vehicle into the sky.

With four of its five engines operating, the rocket’s guidance, navigation, and control system corrected course and tried to compensate for the thrust shortfall. But the vehicle climbed slower than designed. 

After the rocket reached supersonic speed, a range safety officer on the ground issued a flight termination command about two-and-a-half minutes into the flight.

Astra engineers traced the problem to a propellant leak in the quick disconnect interface between the rocket and the launch pad.

The LV0007 mission was built on lessons learned from Astra’s previous orbital launch attempts.

“We’re out of the test flight phase,” Kemp said Monday. “We’ll be resuming with commercial payloads that will be operating for our customers in low Earth orbit. That’s not to say that there won’t be more test flights in the future. We have a new Rocket 4.0. We’ll be flying a few test flights of that next year. And that’s really something that we’ll have the opportunity to focus on right now. But the Rocket 3.X series will go into production, and we’ll go into launch operations.”

Kemp said the Rocket 3 series, in its current configuration, can haul a payload of around 110 pounds (50 kilograms) into a 310-mile-high (500-kilometer) mid-inclination orbit.

He said Astra has more than 50 launches in its backlog.

“I can only imagine that demand will continue to grow as we’ve seen over the past couple of years,” Kemp said. “So I think Astra really is in a position to deliver a payload to precise orbit on a precise schedule. And this precision has a lot of value to our customers, their ability to fly something when they need it flown to exactly the orbit, and have it there in 10 minutes. That’s a pretty powerful, unique capability that really just hasn’t been available at scale in this in this industry before.”

Kemp said Astra will expand to other launch sites. All of the company’s orbital launch attempts so far have lifted off from Alaska.

Astra’s next rocket, LV0008, is “well on its way to being integrated,” Lyon said Monday. Officials said details about the LV0008 launch would be announced soon.

Scott Higginbotham, head of NASA’s CubeSat Launch Initiative at Kennedy Space Center, said Friday that the space agency is the sole customer for the next Astra launch. The mission is part of NASA’s Venture Class Launch Services, or VCLS, program, which awarded Astra a $3.9 million contract last year for a commercial CubeSat launch.

Astra’s first launch for NASA could happen before the end of the year, according to Higginbotham.

NASA and Astra officials declined to identify the launch site for the VCLS demonstration mission, but multiple sources said the mission is currently slated to fly from pad 46, a commercial launch complex operated by Space Florida at Cape Canaveral Space Force Station.

Astra transports its launch vehicles and ground infrastructure from the company’s headquarters in shipping containers, requiring no permanent infrastructure at the launch site. During launch campaigns in Alaska, Astra teams set up the launch pad and rocket in less than a week.

The results from Saturday’s launch suggest no changes are needed on Astra’s next rocket, Kemp said.

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Follow Stephen Clark on Twitter: @StephenClark1.



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