Overcurrent in engine likely cause of Japan’s failed H3 rocket launch

TOKYO. KAZINFORM - The launch failure of Japan's new flagship H3 rocket earlier this month was likely caused by an excessive electric current inside its second-stage engine resulting in the power being cut, the Japan Aerospace Exploration Agency said Thursday, Kyodo reports.

Depending on the cause of the overcurrent, future launch plans of the newly developed rocket's predecessor, the reliable H2A rocket, may also be affected as both share the same equipment for their second-stage engines.

The ignition signal was successfully transmitted from the airframe to the second-stage engine, but the power supply to the engine was cut off after the airframe system detected an abnormality immediately afterward, JAXA said at a panel of the Ministry of Education, Culture, Sports, Science and Technology.

While the engine was equipped with two power sources as a backup, both were cut off. The overcurrent may have been caused by malfunctioning electrical equipment inside the engine, or the airframe control unit itself may have malfunctioned, according to JAXA.

The space agency will analyze detailed data inside the control unit and run tests on the airframe to determine the cause of the problem.

It will also investigate any connection with the rocket's first launch attempt in February, which was aborted due to electrical issues in its first-stage engine.

The rocket's launch attempt on March 7 was initiated as scheduled at around 10:37 a.m. at the Tanegashima Space Center on Tanegashima Island in the southwestern prefecture of Kagoshima.

However, JAXA sent a self-destruct command to the rocket around 15 minutes later when the launch vehicle was deemed incapable of completing its mission.

The rocket's remains, together with its satellite payload, appear to have crashed into waters off the eastern coast of the Philippines, according to the space agency.