Reduced Vertical Separation Minimum

RVSM (Reduced Vertical Separation Minimum) reduces the vertical separation between aircraft from 2,000 ft to 1,000 ft at flight levels between FL290 and FL410 (29,000 to 41,000 ft). This effectively doubles the number of available cruise flight levels in this altitude band.

RVSM requires aircraft to have: two independent altimetry systems, an altitude alerting system, an automatic altitude control system (autopilot), and RVSM approval from the operator state. RVSM has been implemented worldwide since 2005.