DART (satellite) - Mishap Investigation Board

Mishap Investigation Board

NASA convened a mishap investigation board to determine the reason for the DART spacecraft anomaly. First reports pointed to the spacecraft running out of fuel before concluding its mission.

On April 14, 2006 NASA announced that they would not release the investigation's report, citing that the report includes details protected by the International Traffic in Arms Regulations.

On May 15, 2006 NASA released a public summary of the DART mishap investigation board report (NASA press release). NASA revealed that a critical navigation failure occurred when the DART and MUBLCOM spacecraft were about 200 meters apart, which precluded the full activation of the AVGS and allowed DART to approach MUBLCOM without accurate ranging information. A later failure of the collision avoidance system, which was relying upon inaccurate position and velocity information, allowed DART to ultimately collide with MUBLCOM at a relative speed of approximately 1.5 meters per second. Both spacecraft survived the collision without apparent damage. Throughout the autonomous proximity operations, DART used its limited propellant faster than anticipated, which caused "a premature end to the mission" 3 minutes 49 seconds after the collision. DART initiated its retirement programming, removed itself from the vicinity of MUBLCOM, and prepared for deorbit. After the collision, MUBLCOM "regained its operational status after an automatic system reset".

The DART Mishap Investigation Board determined that only 11 of the 27 defined mission objectives were partially or fully met, all of which related to the launch, early orbit, rendezvous, departure, and retirement phases. None of the 14 objectives related to the proximity operations phase were met.