Reduced vertical separation minima - Wikipedia
Reduced vertical separation minimum (RVSM) is the reduction, from 2,000 feet to 1,000 feet, of the standard vertical separation required between aircraft flying between flight level 290 (29,000 ft) and flight level 410 (41,000 ft).Expressed in the International System of Units (SI), it is the reduction, from 600 m to 300 m, of required vertical separation of aircraft between altitudes 8,850 ...