NASA has asked a panel of outside experts to review its investigation into the unexpected loss of material from the Orion spacecraft’s heat shield during a 2022 test flight.
In December 2022, a chunk of charred material cracked and chipped from Orion’s heat shield during atmospheric re-entry at the end of the 25-day unmanned Artemis 1 mission. Engineers who inspected the capsule after the flight found more than 100 locations where debris had broken off from the stress of reentry. As the temperature increases to 5,000 degrees Fahrenheit, the temperature of the heat shield increases.
This was the most important discovery of Artemis I, the first unpiloted test flight of an Orion capsule around the moon. Artemis II, the next mission in NASA’s Artemis program, is scheduled to launch late next year on a test flight that will send four astronauts to the far side of the moon.
another eye
The heat shield, made of a material called Avcoat, is attached to the base of the Orion spacecraft in 186 blocks. Avcoat is designed to ablate or erode in a controlled manner during atmospheric reentry. Instead, debris fell off the heat shield, leaving a cavity that resembled a pothole.
Investigators are still looking for the root cause of the heat shield problem. Since the Artemis I mission, engineers have conducted subscale tests of the Orion heat shield in wind tunnels and high-temperature arcjet facilities. NASA spokeswoman Rachel Craft said NASA replicated the phenomenon observed on Artemis I during these ground tests.
“Research teams are currently synthesizing the results of various tests and analyzes that inform a leading theory about the cause of the problem,” NASA spokeswoman Rachel Craft said.
Last week, nearly a year and a half after the Artemis I flight, the public got its first look at the condition of the Orion heat shield in post-flight photos released in a report from NASA’s inspector general. Cameras aboard the Orion capsule also recorded fragments of the heat shield that broke off from the spacecraft during atmospheric reentry.
NASA’s inspector general said the charring loss problem “creates a risk that the heat shield will not adequately protect the capsule’s systems and crew from the extreme heat of reentry on future missions.”
Victor Glover, pilot of the Artemis II mission, said in a recent interview with Ars: “We’ve seen these photos since they were taken, but more importantly…we’ve seen them… That’s what I did.” “More than any photos or reports, I saw that heat shield, and that determined how interested I was in the details.”
