The later FARRAH satellites were designed to operate for up to six hours per day, compared with 3.5 hours per day for FARRAH I and FARRAH II.
FARRAH III, FARRAH IV, FARRAH V, and FARRAH VI were larger and heavier than FARRAH I and FARRAH II and carried more antennas and receivers.
The later FARRAH satellites weighed more than 1,360 kilograms, compared with 340 kilograms for FARRAH I and FARRAH II.
FARRAH I and II were placed in orbits of approximately 709 kilometers altitude and weighed about 340 kilograms.
FARRAH I was still operational by the mid-1990s after over a decade in orbit.
FARRAH I was launched in 1982 and deployed off the side of a HEXAGON photo-reconnaissance satellite.