Upgraded Starship prototype makes first soft landing after test flight

SpaceX launched and landed an upgraded prototype for the company’s next-generation Starship vehicle in South Texas on Wednesday, the company’s first Starship test flight since winning a $2.9 billion NASA contract to use the craft to land astronauts on the Moon.

Elon Musk, SpaceX’s founder and CEO tweeted: “Starship landing nominal!”

The 164-foot-tall (50-meter) stainless steel rocket flew to an altitude of about 33,000 feet (10 kilometers) over SpaceX’s rocket development and test facility in Cameron County, Texas, after lifting off at 6:24 p.m. EDT (2224 GMT). Around six minutes after takeoff, the rocket landed vertically back at the same test site at Boca Chica Beach near Brownsville.

Three Raptor engines consuming methane and liquid oxygen propellants powered the rocket into the sky, before the engines shut down in a staggered sequence as the Starship neared the high point of its trajectory. After the final engine switches off, cold gas control thrusters and body flaps maneuvered the vehicle to a horizontal orientation for the descent back to the ground.

Moments before the Starship reached the ground the Raptor engines reignited to flip the rocket vertical again and slowed it down for a gentle landing.

SpaceX has successfully launched four Starship prototypes on atmospheric test flights since Dec. 9, but all four rockets exploded during or shortly after landing.

A hard landing on an otherwise-successful Dec. 9 Starship test flight was caused by low pressure from header tanks feeding the vehicle’s Raptor engines for the critical burn just before touchdown, and one of the Raptor engines failed to reignite for the landing burn on a test flight Feb. 2.

The SN10 rocket achieved the first successful landing of a full-size Starship vehicle at the end of a March 3 test flight, but the rocket exploded minutes later after a harder-than-intended touchdown. And the most recent Starship test flight ended with an explosion moments before landing March 30, an accident caused by a methane fuel leak in one of the rocket’s Raptor engines.

The rocket that launched Wednesday, designated Starship Serial No. 15, debuted new upgrades to the Starship design. Last month, SpaceX rolled out Starship SN15 to the oceanside launch pad from the Starship production complex a couple of miles inland from the Gulf Coast.

SpaceX performed two test-firings of the Starship’s Raptor engines April 26 and 27, clearing the say for a launch attempt this week.

Elon Musk said the SN15 prototype introduces “hundreds of design improvements” in structures, engines, avionics, and software.

SpaceX said in a statement Wednesday that the upgrades “will allow more speed and efficiency throughout production and flight.” The changes include “a new enhanced avionics suite, updated propellant architecture in the aft skirt, and a new Raptor engine design and configuration,” SpaceX said.

SpaceX is developing the Starship spacecraft and its huge booster rocket, named the Super Heavy, as a fully reusable launch and space transportation system capable of ferrying more than 100 metric tons of cargo into low Earth orbit, more than any other rocket in the world.

With in-space refueling, the Starship could eventually carry people and heavy supply loads to the Moon and Mars.

Last month, SpaceX won a $2.9 billion contract from NASA to develop a derivative of the Starship vehicle to land astronauts on the Moon through the space agency’s Artemis program. SpaceX bested bids from Blue Origin and Dynetics to win the contract for NASA’s next human-rated lunar lander.

According to NASA’s plans, astronauts will depart Earth on the agency’s government-owned Space Launch System rocket and Orion crew capsule, then rendezvous with a Starship pre-positioned in lunar orbit. The Starship would launch from Earth without anyone on-board.

After landing on the Moon, the astronauts will exit the Starship and ride an elevator down to the surface. Once their work is complete, the crew members will launch on the Starship back into lunar orbit, meet up with the Orion capsule, and return to Earth.

After several more Starship test flights in the coming months, the next major technology update to the Starship vehicle will come with SN20 later this year, according to Musk. Beginning with SN20, the Starship vehicles will be capable of flying into low Earth orbit on top of SpaceX’s Super Heavy booster, and they will be fitted with a heat shield to withstand the high temperatures of atmospheric re-entry.

Musk tweeted earlier this year that the Super Heavy/Starship combination will initially have a high probability of achieving a successful launch into orbit, but it will likely take many attempts before SpaceX perfects the Starship’s re-entry and landing maneuvers from orbit.

SpaceX has built a Super Heavy production test article in South Texas, but the company has not yet attempted the first Super Heavy test flight.

The orbital version of the Starship vehicle will have six Raptor engines, including three engines with enlarged bell-shaped nozzles optimized for higher efficiency in the vacuum of space. The Super Heavy will have 28 Raptor engines, producing some 16 million pounds of thrust, twice the power of NASA’s Apollo-era Saturn 5 rocket.

The entire Super Heavy/Starship rocket stack will stand nearly 400 feet, or about 120 meters, tall.

During an orbital launch attempt, a reusable Super Heavy first stage booster will detach from the Starship — which acts as both an upper stage and in-space transporter — and come back to Earth for a vertical landing, where catcher arms on the launch tower will try to capture the descending first stage.

The Starship will continue into orbit and deploy its payloads or travel to its deep space destination, and finally return to Earth to be flown again.

SpaceX has succeeded in cutting launch costs with the Falcon 9 rocket, which has a reusable first stage and payload shroud. But neither part is rapidly reusable, and the Falcon 9’s second stage is brand new for every mission.

“With Starship, we’ll hopefully reuse the whole thing,” Musk said last month. “This is a hard problem for rockets, that’s for sure. It’s taken us, we’re like 19 years in now. I think the Starship design can work. It’s just, it’s a hard thing to solve, and the support of NASA is very much appreciated in this regard. I think it’s going to work.”

Musk eventually wants to have a fleet of ocean-going platforms to recover and re-launch Super Heavy boosters and Starship rockets.

“It’s intended to be such that the booster can be used, I don’t know, a dozen times a day, basically every couple of hours,” Musk said in an XPRIZE webcast last month. “And that mostly is about reloading propellant and mounting the ship. and then the ship can probably be used, in theory, every three hours … But certainly every, say, six to nine hours. We’ll call it twice a day for the ship. And we’ll make more ships than there are boosters.

“Once we have the floating space platforms, we can position them such that the ship can come back in a single orbit,” Musk said. “So then it can be, let’s say we have three ship launches per day, that’s 1,000 flights a year, each with 100 to 150 tonnes of payload to orbit.”

“I’d say it’s only recently though that I feel that full and rapid reusability can be accomplished,” Musk said. “I wasn’t sure for a long time, but I am sure now.”

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Follow Stephen Clark on Twitter: @StephenClark1.