17.07.2024

SpaceX wants the Federal Aviation Administration to let its grounded Falcon 9 rocket fleet return to flight amid an ongoing public-safety investigation, letting the company resume its array of uncrewed commercial missions while engineers study what happened during Thursday's upper-stage malfunction.

But what about Falcon 9 missions with humans on board?

Polaris Dawn, a mission featuring billionaire commander Jared Isaacman and three fellow commercial astronauts in a SpaceX Dragon capsule, was scheduled to lift off as early as July 31 from Cape Canaveral Space Force Station. Following suit, NASA's Crew-9 was slated to launch as soon as August to the International Space Station.

"What I would imagine the requirement will be is that, they understand what happened. They have a plan to fix it. And they fly at least one non-crewed Falcon 9 to verify the fixes before Polaris Dawn is cleared to go," said Jonathan McDowell, an astrophysicist at the Harvard–Smithsonian Center for Astrophysics.

"And that's not really going to be a problem, because they've got a lot of Falcon 9s backed up, raring to go," McDowell said.

Assuming that SpaceX adds instrumentation to the rocket upon return to flight to collect extra diagnostics for investigators, McDowell said, "the question is whether it's weeks or months," before the FAA grants permission to resume crewed missions.

On Monday, SpaceX requested that the FAA agree that last week's anomaly did not jeopardize public safety, clearing Falcon 9s to return to flight while the investigation remains open. The ill-fated rocket, which carried a payload of 20 Starlink satellites from Vandenberg Space Force Base in California, developed a liquid oxygen leak on its second, upper stage — unexpectedly forcing deployment of the satellites into a too-shallow orbit.

"The FAA is reviewing the request and will be guided by data and safety at every step of the process," an agency statement said of SpaceX's Monday request. Further details remain unknown.

“It’s going to impact crewed launches more than (regular) launches because they’re going to make sure that they have everything absolutely figured out and safe before they put another crew on board,” said Laura Forczyk, founder and executive director of the Atlanta space consulting firm Astralytical.

Falcon 9s launched 46 of 50 Florida missions

Meanwhile, the Space Coast's launch schedule — which was speeding along this year at a record-breaking pace — remains largely on indefinite hold. Falcon 9s have accounted for 46 of the 50 missions launched during 2024 from Cape Canaveral Space Force Station and adjacent NASA's Kennedy Space Center.

In a statement, SpaceX pledged to "perform a full investigation in coordination with the FAA, determine root cause, and make corrective actions to ensure the success of future missions." Per the federal agency, "a return to flight is based on the FAA determining that any system, process, or procedure related to the mishap does not affect public safety."

FLORIDA TODAY reached out to NASA, which sent the following statement via email:

“Although the SpaceX Starlink launch was a fully commercial mission, NASA receives insight from SpaceX on all items of interest about the Falcon 9 rocket, as part of the agency’s standard fleet following activities. Crew safety and mission assurance are top priorities for NASA," the statement said.

"SpaceX has been forthcoming with information and is including NASA in the company’s ongoing anomaly investigation to understand the issue and path forward. NASA will provide updates on agency missions including potential schedule impacts, if any, as more information becomes available," the statement said.

John Holst, a Florida-based space consultant and author of the blog Ill-Defined Space, said SpaceX has a history of being open about problems.

“These are rare for SpaceX. So SpaceX, I’m sure, is going to try to quickly go through this, but at the same time, the FAA and NASA has their mission-assurance process that they would like to go through and understand exactly what happened," Holst said.

"Because they don’t want a second stage to go incorrect — RUD (rapid unscheduled disassembly) — underneath the astronauts trying to get to orbit,” he said.

What FAA, SpaceX may find during investigation

McDowell said SpaceX operates under the philosophy "good enough is never good enough."

"They keep futzing with the design and improving and changing, right? They're in that Silicon Valley mode, rather than the old NASA mode of, 'Yeah, once you've got it working, don't change a thing,' " he said.

"Was this (anomaly) the result of a change in the design? It's not going to be a fundamental flaw in the existing design, because they've had so many launches. So the other possibility is, it was a screwup in manufacture or assembly. And that's what the investigators have to look at," he said.

McDowell said SpaceX and the FAA have to ensure that a potential problem will not impact the Polaris Dawn mission. If the same upper-stage oxygen leak mishap were to occur during Polaris Dawn, he said SpaceX would lose the mission, not the crew — which could maneuver the Dragon to an emergency return to Earth.

He said he will be surprised if it takes more than a month for SpaceX engineers to zero in on the root cause and its solution for uncrewed Starlink missions — but "then the question is, how long will it take for the FAA to be happy?"

What happened to the Falcon 9 upper stage?

During Thursday's California launch, SpaceX reported that the Falcon 9 first stage performed nominally, lifting the second stage and Starlink satellites to orbit before returning to Earth for a successful drone ship landing,

"The second stage boosts into a very low Earth orbit, then coasts for about 40 minutes to the high point of that orbit, and then restarts (its engine) to get to the orbit they're going to deploy all the Starlink satellites into. And what happened this time is that that restart did not happen," McDowell said.

SpaceX reported the satellites were left in an eccentric orbit only 135 kilometers above the Earth's surface, or less than half the expected perigee altitude.

"The density of the atmosphere is quite high, and the drag that the satellites experience plowing through that upper atmosphere is going to bring them down pretty quickly. And worse, the little argon electric thruster rocket engines on the satellites are not powerful enough to overcome that drag," McDowell said.

"So although SpaceX tried to fire those rocket engines to save the satellites and bring them up to higher orbit, they just didn't have the oomph to overcome the drag at that low altitude," he said.

"And so within, probably I would guess a few hours to a day, all of those suckers were down — burnt up in the atmosphere," he said.

Companies awaiting return to flight

Beyond satellites, the Falcon 9 has launched a colorful variety of missions into orbit this year from the Space Coast, including:

• Axiom Space's third crew of private astronauts, which trekked to the International Space Station in January.
• NASA's PACE spacecraft, which will study Earth's oceans and atmosphere, in February.
• The Space Force's USSF-124 national security mission, also in February. 
• NASA's SpaceX Crew-8, which reached the ISS in March. 

The day after Crew-8 lifted off in March, Cape Canaveral-based Sidus Space hit a critical corporate benchmark by launching its first satellite, LizzieSat-1, aboard a Falcon 9 on SpaceX's Transporter-10 rideshare mission from Vandenberg.

"I'm shocked. They've been pretty successful," Mark Lee, Sidus Space lead quality inspector, said of Thursday's mishap. He said his company plans another launch later in the year, and he hopes the FAA grounding will not greatly impact that timing.

Now commonplace on the Space Coast, Starlink launches do not garner the same interest — or crowds of spectators — that high-profile rockets like SpaceX's Falcon Heavy do.

"We don’t anticipate any immediate impact as summer vacationers have mostly made their plans," Space Coast Office of Tourism Executive Director Peter Cranis said in an email of the FAA grounding.

"There is always a bit of a slowdown in September into the fall, so we don’t anticipate it will be any different this year," Cranis said.

Quelle: Florida Today