Japan's space agency says the launch failure of its Epsilon-6 rocket last year was caused by a rubber membrane clogging a fuel pipe for the direction control system.

The rocket lifted off from the Uchinoura Space Center in southwestern Japan on October 12. But the command center sent a self-destruct signal minutes later because the vehicle's direction control system did not function properly.

The Epsilon is a roughly 30-meter-long vehicle designed to send satellites into space at a low cost.

Officials from the Japan Aerospace Exploration Agency, or JAXA, reported to an expert panel of the science and technology ministry on Tuesday on the suspected cause of the direction control system's malfunction.

They said they conducted simulations of the malfunction and collected data on the related parts. This helped them to determine that a damaged rubber membrane in a fuel tank clogged a pipe connected to the tank, leading to the malfunction.

The officials also said the membrane was damaged because part of it got stuck between the tank and its fixing device when it was set.

The officials noted that the parts were not checked sufficiently as they had a proven track record.

They said they want to improve reliability by reexamining the design concept at the time of development, the conditions under which the parts can be used and the manufacturing process.

JAXA is working to launch the Epsilon S, an improved version of the current vehicle, next fiscal year. The officials say they will review the design of the fuel tank in question.