From the inlay (ZX81 release):
FLIGHT Simulation is an extraordinary program which uses the ZX81 in real-time to its fullest capability. The outstanding graphic display shows the many cockpit instruments and the outside world through the cockpit windows. As you bank, dive and climb, the sky and ground move through the windows. In the final landing a full perspective, moving view of the runway is shown.
Over the last decade, with the increasing power of computers, pilots have been trained to "fly" new airliners on large scale, computer-controlled simulators on the ground. Even on a small microcomputer like the Sinclair ZX81 the essential parameters of flight, the dynamics of the aeroplane, the navigation of the aeroplane, the main instruments and the representation of the outside world can be portrayed in real time. "FLIGHT Simulation" includes these effects and represents a small, high-performance, two-engined, propeller-driven aeroplane.