The RAE performed a multitude of studies on the subject of prospective derivatives of the Black Knight and its Gamma engine. Many of these focused on the possibility of extending the vehicle to operate a launcher for small satellites and proposed the use of liquid hydrogen-fuelled upper stage, which was comparatively expensive to develop while not providing much payload capacity without redesigning of the Black Knight vehicle itself as well. An alternative solution for satellite launches was explored by the RAE, in which solid fuel boosters would have been attached to the Black Knight. This proposal would have involved a basically unmodified Black Knight vehicle being paired with two strap-on boosters along with two further stages in order to be capable of placing a 100 lb payload into a 200-mile-high orbit. While this implementation was found to be simple and low-cost to develop, the payload capacity remained low.