NASA’s October 15, 2026, postflight assessment found Orion’s Artemis II aerodynamic and thermal performance—including its heat shield and backshell—was in line with preflight engineering predictions based on analysis and ground testing. NASA counted nine char-loss spots of varying sizes on the Artemis II heat-shield dish, compared with 103 on Artemis I. NASA’s assessment reports both the comparison and a separate reduction in cracking and char loss.
What NASA counted
NASA reported these numbers of char-loss spots on the two heat-shield dishes:
| Mission | Char-loss spots |
| Artemis II | 9 |
| Artemis I | 103 |
Separately, NASA said cracking and char loss were reduced by a factor of ten compared with Artemis I. NASA attributed that broader reduction to a change in Orion’s entry profile; the factor-of-ten assessment is distinct from the spot counts.
How the entry profile changed
NASA shortened the maximum allowable downrange distance—the distance Orion could travel along its entry path before splashdown—to limit the spacecraft’s time in a temperature range associated with the Artemis I heat-shield phenomenon. NASA’s preflight analysis predicted that this change would reduce time in that range, and its postflight assessment attributed the lower cracking and char loss to the modified profile.
Orion’s heat shield consists of 186 unique blocks of ablative Avcoat, a material designed to protect the spacecraft by wearing away under intense heat. During Artemis II’s return, NASA reported a peak external temperature above 4,000°F, while the cabin remained in the mid-70s°F. The backshell inspection also found expected performance across its surface, with no visible signs of overheating.
Why Orion banks and rolls
Banking and rolling help Orion manage its lift vector—the direction of aerodynamic lift—and control its entry trajectory and landing targeting. NASA technical papers describe this as general Orion flight-mechanics context. One paper on Orion entry options and a paper on entry trajectories address those control goals.
Analysis NASA said was continuing
In its October 15 account, NASA said it was comparing postflight laser scans with preflight measurements to determine material recession. Sample extraction, material testing, and thermal analysis were also continuing.
