D. Composite fuel rocket engine installed and ready
for liftoff. E. Carefully designed fins keep the rocket
Amateur Rocketry Basics
Most model rockets use small black-powder
motors ranging up to D size. The power and
impulse of model rockets are comparatively small.
Therefore, safety concerns and costs are minimal.
A step beyond model rocketry are mid-power
rocket engines that range from class E to G. While
mid-power engines can be powered by black-powder cartridges, very often they’re made from
composite propellants. Composite engines consist
of a rubbery plastic fuel, a powdered oxidizing
chemical, and various additives, and they’re more
powerful on a unit weight basis than black-powder
rockets. They generally weigh less than a pound,
and can fly much higher than model rockets.
The largest rockets built with commercially manufactured motors are called high-power rockets.
High-power motors range in size from H through
O. An O motor is big, roughly 16,000 times the
size of an A model rocket engine. Typically, high-power rocket motors require federal licensing
and approvals to purchase and fly, and can be
flown only at organized club launches held in
large, open, unpopulated areas.
Beyond high-power comes the realm of experimental rocketry. It’s for those who choose to
build their own rocket motors rather than use
commercially manufactured ones. Motors can
be any size, though generally they’re very large.
Interested in making your own rocket?
Visit these websites for more info:
William Gurstelle is a contributing editor for MAKE. His
fifth book, Whoosh Boom Splat, went on sale in March.