When A Workhorse Falters

Falcon 9 launch A Falcon 9 launched a Turkish communications satellite last Monday, the last successful flight of the rocket before an upper-stage anomaly on a launch Thursday night. (credit: SpaceX) When a workhorse falters by Jeff Foust Monday, July 15, 2024 Bookmark and Share Last week was not shaping up to be a great week for launch vehicles even before Thursday night. On Wednesday, a small Chinese commercial rocket, the Hyperbola-1 from iSpace (not to be confused with Japanese lunar lander developer ispace) failed to reach orbit when the fourth stage of the solid-fuel rocket suffered an unidentified anomaly. It was the fourth failure in seven flights for that rocket. Stéphane Israël, CEO of Arianespace, said his company was “perfectly on track” to conduct the vehicle’s second launch late this year despite the APU problem. That launch came a little more than 24 hours after the long-anticipated debut of Europe’s Ariane 6. The rocket lifted off Tuesday afternoon from French Guiana and initially performed well, reaching orbit and deploying a set of cubesats. ESA even issued a statement declaring the launch a success. “I am privileged to have witnessed this historic moment when Europe's new generation of the Ariane family lifted off—successfully—effectively reinstating European access to space,” said Josef Aschabacher, ESA’s director general, in that statement. However, when that statement was issued the rocket still had one final maneuver to perform: a deorbit burn to put the spacecraft onto a trajectory to burn up over the South Pacific. It would also deploy two small reentry capsules attached to the upper stage, one developed by The Exploration Company, the European startup selected by ESA in May to begin design work on a spacecraft to ferry cargo to and from low Earth orbit. That deorbit burn did not take place. An auxiliary power unit (APU) that pressurizes the liquid oxygen and hydrogen tanks malfunctioned, keeping the Vinci engine from reigniting. The stage was left in low Earth orbit, its reentry capsules still attached. (Ironically, it comes as ESA emphasizes a “zero-debris” policy intended to prevent the disposal of upper stages in orbit.) Officials played down the incident at a post-launch press conference. Stéphane Israël, CEO of launch services provider Arianespace, said his company was “perfectly on track” to conduct the vehicle’s second launch, and first operational mission, late this year. That mission, the payload for which has not been disclosed, likely will not need the multiple ignitions of the Vinci engine planned for this mission. Other customers, though, such as Amazon’s Project Kuiper, likely will need multiple relights for their satellite deployments. The Chinese launch failure and Ariane 6 upper stage anomaly were overshadowed, though, by what took place Thursday night. A Falcon 9 lifted off from Vandenberg Space Force Base in California on what has become a routine mission for the rocket, carrying 20 Starlink satellites. The first stage performed nominally and landed on a droneship in the Pacific, completing its 19th flight. Those watching the webcast, though, noticed something unusual from the cameras on the second stage as it ascended to orbit: a buildup of ice on parts of the engine. The company didn’t comment on the ice buildup on the webcast and ended it, as usual, after the first stage landed and the second stage completed its initial burn. The second stage was scheduled, about 52 minutes after liftoff, to perform a brief second burn to circularize its orbit, followed by deployment of the Starlink satellites. That time came and went without any updates from the company. Two hours after launch, SpaceX CEO Elon Musk posted on X (formerly Twitter), his social media company. “Upper stage restart to raise perigee resulted in an engine RUD for reasons currently unknown,” he said. “RUD” is an acronym popularized by SpaceX for “rapid unscheduled disassembly,” suggesting the engine exploded. The bigger impact from the failure is not the loss of 20 Starlink satellites but the grounding of the Falcon 9. Exactly what happened to the upper stage is not yet clear. In a statement Friday, SpaceX said there was a leak of liquid oxygen in the second stage, which would explain the ice buildup seen on the webcast. “After a planned relight of the upper stage engine to raise perigee – or the lowest point of orbit – the Merlin Vacuum engine experienced an anomaly and was unable to complete its second burn,” it stated. It added, though, that the stage “survived” that anomaly and was able to deploy the satellites and “passivate” itself, removing sources of energy that could cause an explosion. The low perigee of that transfer orbit, just 135 kilometers, doomed the Starlink satellites. The electric thrusters on those spacecraft, while very efficient, are not strong enough to overcome the high atmospheric drag at that low altitude. Musk said engineers updated software for the thrusters to operate them “at their equivalent of warp 9. Unlike a Star Trek episode, this will probably not work, but it’s worth a shot.” Indeed, the additional thrust was not sufficient, and the satellites did not survive. The bigger impact from the failure is not the loss of 20 Starlink satellites but the grounding of the Falcon 9. While the term “workhorse” is often overused, it is clearly applicable to that vehicle, which large parts of the global space community have used and increasingly relied upon given a lack of capacity elsewhere in the market. The Starlink launch was the 70th this year for the Falcon family, including one flight so far of the Falcon Heavy. Starlink was by far the largest single customer for the vehicle, but so far this year the vehicle launched astronauts and cargo to the International Space Station for NASA, Earth science satellites for NASA and for ESA, Galileo navigation satellites for the European Commission, a lunar lander for Intuitive Machines, communication satellites for several companies, dozens of classified satellites, and a wide range of smallsats on rideshare missions. Among others. Many of those customers came to SpaceX because of a lack of options elsewhere, including their own vehicles. Northrop Grumman used a Falcon 9 to launch a Cygnus cargo spacecraft in January while its own Antares rocket is being upgraded in cooperation with Firefly Aerospace. Ariane 6 delays forced the European Commission to launch Galileo satellites on Falcon (even if it would only refer to the rocket as “the launcher” in public statements about it.) Issues with the smaller Vega C led ESA to launch the EarthCARE mission on a Falcon 9. That reliance means that many customers are affected by even a short-term grounding of the rocket. In the near term, the biggest impact is on NASA. A Falcon 9 was scheduled to launch another Cygnus cargo spacecraft in early August, followed later in the month by the Crew-9 mission. Both are now likely to be delayed A Crew-9 delay in particular has ramifications for ISS operations, since the Crew Dragon spacecraft for Crew-8 will likely have to return no later than September, after six months in space. That would reduce the station’s crew to three, with just one NASA astronaut, Tracy C. Dyson, affecting ISS operations. (This assumes, of course, that Starliner returns in late July or early August, but right now, who knows?) “I have no doubt they will arrive at a cause quickly and ensure the most cost-effective and reliable launch vehicle keeps delivering payload to orbit,” said Isaacman. NASA hasn’t offered any insights into its thinking on ISS operations or other effects of the failure. “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,” NASA said in a statement late Friday, adding that SpaceX had included NASA in the investigation. “NASA will provide updates on agency missions including potential schedule impacts, if any, as more information becomes available.” Also on hold is another private astronaut mission, Polaris Dawn. That mission was scheduled to launch as soon as the end of July, launching a four-person crew on a Crew Dragon that would demonstrate, among other things, new EVA suits developed by SpaceX. It is part of the Polaris program of private missions backed by Jared Isaacman, the billionaire who led the Inspiration4 mission in 2021. “I have no doubt they will arrive at a cause quickly and ensure the most cost-effective and reliable launch vehicle keeps delivering payload to orbit,” Isaacman, who will command Polaris Dawn, stated after the Falcon 9 failure. “As for Polaris Dawn, we will fly whenever SpaceX is ready and with complete confidence in the rocket, spaceship and operations.” Many other customers are affected by the failure, including returning customers. The European Commission planned to launch two more Galileo satellites on a Falcon 9 this fall, while ESA’s Hera asteroid mission—a followup to NASA’s DART planetary defense mission to the asteroid Didymos—is scheduled in October. NASA’s Europa Clipper mission is scheduled to launch in a three-week period in October on a Falcon Heavy, whose upper stage is similar to the Falcon 9 upper stage. (That mission, though, has problems of its own involving transistors that may not be as radiation tolerant as expected.) The level of impacts caused by the anomaly will depend on how long the rocket is grounded. The FAA is involved in the investigation and noted in a statement Friday that it will have to approve SpaceX’s report into the investigation and corrective actions before allowing launches to proceed. However, it added that its focus is on “determining that any system, process, or procedure related to the mishap does not affect public safety.” An upper stage malfunction has limited effects on public safety, which could accelerate the approvals it provides. One industry source, speaking on background, said the best-case scenario would be for SpaceX to rapidly track down and correct a minor manufacturing defect with the stage and resume launches in a matter of weeks, starting with Starlink satellites to demonstrate to other customers the vehicle is safe for them. An investigation that drags on for months, though, would be “catastrophic” for much of the industry, that person warned. That’s because there are few options for customers to turn to. Other vehicles are either not flying or have full manifests for years to come. Even as vehicles like Ariane 6, H3, Vulcan Centaur and (soon) New Glenn start flying, they have large backlogs of customers to fly and little ability to squeeze new customers in. A situation where the malfunction of a single vehicle can disrupt plans by many companies and agencies, with little recourse, is not sustainable for the industry for the long term. Last month, ULA announced it would fly an inert payload on its second Vulcan launch in September because of delays in the final testing of Sierra Space’s Dream Chaser spacecraft. ULA wants to launch by September to secure certification by the Space Force for national security launches scheduled before the end of the year. ULA CEO Tory Bruno, posting on social media Sunday, ruled out flying a customer payload on that Cert-2 mission instead of the mass simulator. “We have a high priority national security launch directly after Cert-2 that must be preceded by Cert-2, and the USG’s [US government’s] evaluation of the Cert-2 data. So, it’s not worth risking a potential delay in either integration or the payload being late,” he said. Even if quickly resolved, the failure shows the relative brittleness of space access today. A situation where the malfunction of a single vehicle can disrupt plans by many companies and agencies, with little recourse, is not sustainable for the industry for the long term. A vibrant industry needs multiple ways of getting to space, each with its own specific value propositions—low cost, high performance, etc.—but with enough overlap to provide for competition and alternatives. Until then, the growth of the space economy will remain limited. Jeff Foust (jeff@thespacereview.com) is the editor and publisher of The Space Review, and a senior staff writer with SpaceNews. He also operates the Spacetoday.net web site. Views and opinions expressed in this article are those of the author alone.