Mitsubishi Heavy Industries Ltd. began production June 20 of a full-scale trial unit of the upper and lower domes of the fuel tanks for the H-2B rocket, Japan’s next- generation launch vehicle.

The H-2B, under development by the Japan Aerospace Exploration Agency and Mitsubishi, is an enhanced version of the H-2A. The H-2B will have two LE-7A rocket engines for the first stage firing and 5.2-meter fuel tanks, compared to 4-meter tanks for the H-2A. The H-2B, scheduled for its initial launch in 2008, is designed to loft up to 8 tons into orbit.

The domes, when combined with the fuel tanks, will account for the majority of the rocket’s volume. The finished domes will be transferred to Nagoya Aerospace Systems Works, where they will be integrated with a cylinder to form the fuel tank.