Investigators have pinpointed the reason a suborbital sounding rocket fizzled just after launching from Wallops Flight Facility last summer on a mission to test suborbital rocket technologies, NASA said Monday.
The space agency’s Anomaly Investigation Board determined that an igniter was improperly installed on the second-stage motor of the Terrier-Improved Malemute rocket. And when the motor was ignited, the pressure ejected the igniter, causing the motor to burn from both ends and the rocket to fall into the Atlantic.
The Terrier managed to reach an altitude of 27,000 feet before it fell about one nautical mile downrange from the launch pad on Wallops Island on the Eastern Shore. The flight lasted about 19 seconds.
Phil Eberspeaker, chief of the Sounding Rocket Programs Office at Wallops, said he accepts the board’s finding.
“(Its) recommendations are being applied in the program and clears the way for the launch of two Terrier-Improved Malemute vehicles in January … from the Poker Flat Research Range in Alaska,” Eberspeaker said.
Five months after the Terrier rocket failed, the spaceport at NASA Wallops suffered a second and more massive failure when a medium-lift Antares exploded seconds after launch on a mission to resupply the International Space Station. Preliminary evidence indicates that failure was caused by a faulty first-stage engine.
The Improved Malemute is a military surplus solid-fuel motor the agency modified for use in its sounding rocket program to conduct science experiments. NASA developed the igniter.
According to board chairman Brian Hall, they found that incorrect installation of the motor clip was due to “inadequate procedures for the NASA modification.”
“The board recommended the corrective action is to update the modification procedures, including adding drawings and verbiage for correct installation and verifying that the clip is properly installed after placing the igniter in the motor,” Hall said.