The agency suspected liquid hydrogen had leaked out of a fuel tank and ignited in contact with oxygen, in the latest gremlin to hit Japan's troubled space programme.

The agency said it conducted a ground firing test on the rocket last Wednesday and discovered a faulty valve in the engine's liquid-hydrogen pump.

"We learned something was wrong with the engine when detecting a fire near it during the test," said Yoichi Fujita, a spokesman for the space agency.

"The valve in the liquid-hydrogen pump failed to close when it was supposed to close," Fujita said.

"We will investigate the failure thoroughly," the spokesman added, but the failure would not derail the rocket's first launch.

"We will proceed as planned," Fujita said. "The failure itself is marginal and by itself does not pose any problem for a normal launch."

The agency will conduct another test in August.

The H-2A rocket, a high-performance but cheaper version of the H-2, is scheduled to carry a European data-transmission satellite in the February launch.

In November last year, space authorities exploded a 24-billion-yen (224-million-dollar) H-2 rocket and satellite by remote control when it veered off course after lift-off.

And in February 1998, a 36-million-dollar satellite was lost in space despite a successful separation from an H-2 rocket because it was released at the wrong altitude and sent into an elliptical orbit.

The H-2 is Japan's answer to Europe's successful Ariane-4.

The spectacular rocket failures forced NASDA to postpone the launch of the next generation H-2A rocket, orginally scheduled for last February.

JAPAN SPACE
H2 Grounds NASDA President
Tokyo (AFP) May 18, 2000 - Japan's top space development official resigned Thursday in a move linked to the explosion of its 220-million-dollar mainstay H-2 rocket last November.