Engine Model: MB-60. Manufacturer Name: RS-73. Other Designations: MB-XX. Designer: Rocketdyne. Developed in: 1999. Propellants: Lox/LH2. Thrust(vac): 266.700 kN (59,957 lbf). Isp: 467 sec. Mass Engine: 591 kg (1,302 lb). Length: 3.30 m (10.80 ft). Chambers: 1. Country: Japan. Status: Design 2004. MHI (Mitsubishi Japan)/Boeing joint project for an engine for Delta IV cryogenic upper stages. Expander bleed, pump-fed. Boeing’s Rocketdyne Division (USA) and Mitsubishi Heavy Industries (Japan) had announced on 14 February 2000 their agreement to jointly design and develop the MB-XX family of high-power cryogenic upper-stage engines for Boeing’s Delta-4 and Japan’s H-2A launch vehicles. In 2005 the MB-XX was being demonstrated on funding from Boeing and Mitsubishi Heavy Industries for potential application to the Vision for Space Exploration launch vehicle or upgrades to today's EELVs.
