High, rearview of the Chevrolet Astro III concept vehicle while on display at the 1969 Chicago Auto Show. Considered a potential high-performance vehicle for restricted-access highways, the Astro III had a tricycle-wheel layout, a rear-mounted Allison gas turbine engine, and rear-vision closed-circuit TV. A low center of gravity would help keep the car stable, and a canopy lifted to provide access to the aircraft inspired cockpit.