Abstract: The invention relates to a process for the visual display of the attitude of an aircraft to assist piloting or flying in space. On the basis of the values of cardan or gimbal angles (.psi., .theta., .phi.) of the aircraft marked in a reference mark linked with the celestial cavity or firmament and on the basis of a calculation of quaternions, the process consists of displaying on a screen (1) on board the aircraft, in particular the following informations: a cruciform reticule (7,8,9), a piloting or flying circle B, the value of the roll angle (.phi.) in a scale (10), a net formed by portions of meridians (M) and parallels (P) of the celestial cavity, a symbol (V1) representing the direction pointed by the velocity vector of the aircraft, a short term prediction vector (12) for the aircraft attitude, as well as numerical values (19,21,23) for the roll, pitch and yaw velocities. Application is to the piloting of an aircraft in space.