We are fascinated by the hybrid rocket engine which [Ben Krasnow] built and tested in his shop. It is actually using a hollow cylinder of acrylic as the fuel, with gaseous oxygen as an oxidizer.

The Storm models get darker color schemes with anodized ... a 4.76-gallon fuel tank, and a claimed fuel economy of 35.6 mpg.

is repackaged from the backend of Space Shuttle Orbiters into a more traditional inline rocket stage. SLS upsized the Shuttle elements — the big fuel tanks are now longer, and there are more ...