PPRuNe Forums - Knowledge regarding FANS, MNPS, RVSM, RNAV, RNP

FANS stands for Future Air Navigation System. FANS1 is the Controller Pilot Data link communication system in current use. MNPS is Minimum Navigation Performance Specification. This defines the navigation systems that are required on aircraft flying in MNPS airspace, e.g. The North Atlantic. There is a whole book on this and the latest MNPS document can be found quite easily online. RVSM is reduced vertical separation minima and is the reduction from 2000 feet to 1000 feet separation between flight levels 290 and 410, which means that 6 extra flight levels are available. Again RVSM covers areas and has even extended recently to Africa. RNAV is area navigation, and in a nutshell is the ability to fly directly to any waypoints rather than from fixed beacon to beacon. RNP stands for Required Navigation Performance, and the ICAO definition is "a statement of the navigation performance necessary for operation within a defined airspace". Part of a broader concept called "Performance-based Navigation," RNP is a method of implementing routes and flight paths that differs from previous methods in that not only does it have an associated performance specification that an aircraft must meet before the path can be flown but must also monitor the achieved performance and provide an alert in the event that this fails to meet the specification. It is the monitoring and alerting facility that distinguishes RNP from which it developed. If you see something described as being RNP4, it means that is able to be within 4 nautical miles of where it should be for 95% of the time. Obviously these are all large subjects and google can help you find more on individual items.