The engine of Japan's flagship new small rocket explodes during a test for a second time

TOKYO — The engine for a new flagship small Japanese rocket burst into flames Tuesday during a combustion test, causing no injury or damage to the outside but destroying the engine and extensively damaging its test facility, officials said.

The second failure in a row raises concern about the progress of the Epsilon S rocket, whose debut flight is expected by March.

The test was conducted inside of the restricted area at Japan’s Tanegashima Space Center in southwestern Japan, and the Japan Aerospace Exploration Agency is investigating, Chief Cabinet Secretary Yoshimasa Hayashi told reporters.

An Epsilon project manager, Takayuki Imoto, told an online press conference from Tanegashina that the explosion occurred 49 seconds into the planned two-minute test, causing fire and scattering broken parts of the engine and damaging the facility.

“We are very sorry to have failed to live up to expectations,” Imoto said. He said the cause of the explosion was still under investigation. Project staff are trying to recover broken pieces to analyze and determine the cause as soon as possible to minimize the delay of the program, Imoto said.

He said repairs to the test facility would take several months.

Tuesday’s failure comes just over a year after the explosion last year of another Epsilon S engine during a test, according to JAXA.

Last year’s explosion was related to damage to the ignition systems of the engine and JAXA has since taken the necessary steps, the agency has said.

The triple-stage, 27-meter (88-foot) -long Epsilon S rocket is meant to improve Japan’s position in the growing satellite launch market by using solid fuel for more flexibility and mobility.

Japan’s much larger H3 rocket, failed in its debut launch in February 2023 but has since made three consecutive successful flights, most recently earlier in November.

“Development of flagship rockets such as Epsilon S is extremely important from the perspective of ensuring autonomy of Japan’s space development,” Hayashi told reporters. “JAXA will thoroughly investigate and take steps.”