ORBITAL SCIENCES (OSC) and Rockwell have stopped design work on the X-34B launcher project, although NASA, which is partially funding the work, has not yet cancelled the programme.
The choice of propulsion system for the X-34B, which was to have been launched atop a Boeing 747 NASA Shuttle Carrier Aircraft, caused difficulties between OSC and Rockwell. OSC favoured a Russian RD-120 engine, while Rockwell wanted to use an engine produced by its Rocketdyne division. The unpredictability of the low-Earth-orbit launch market was an additional factor in the decision to halt the design work.
Source: Flight International
