the terms seemed to have been mixed up recently
I always thought of EX as being any rocket of conventional hobby materials flying on home-made solid propellant or hybrid motors. The rocket may be a commercial kit, strengthened to withstand additional stress, or a scratch-built; but would be made of essentially composite materials.
AM, as I understood it, could include any imaginable material, including a significant percentage of metal; and any conceivable fuel (including liquid fuels)
Some of the rockets John has students build at Rocket Camp may meet the description of EX I offered, above.
see
- iz
Bob Kaplow wrote: