Runway Visual Range (RVR) is the range over which the pilot of an aircraft on the centre line of a runway can see the runway surface markings or the lights delineating the runway or identifying its centre line.
Source: ICAO Annex 3: Meteorological Service for International Air Navigation
RVR is not an observation or a measurement of a meteorological parameter (such as e.g. surface wind direction and speed, temperature and pressure). It is an assessment, based on calculations that take into account various elements, including atmospheric factors such as extinction coefficient of the atmosphere, physical/biological factors such as visual threshold of illumination, and operational factors such as runway light intensity.
The main purpose of RVR is to provide pilots, controllers and other aeronautical users with information on runway visibility conditions during periods of low visibility, due to e.g. fog, precipitation or a sandstorm. It is required to assess whether the conditions are above or below the specified operating minima for take-off and landing. It is to be noted that for this purpose RVR values supersede the reported visibility and that in the case of precision approaches it is normally not permissible to start an approach if the applicable RVR value(s) is below the required minimum.
RVR information is provided when the visibility or RVR for a particular runway is below 1500 m. It is representative for:
- The touchdown zone, when the runway is intended for non-precision approaches or Category I operations.
- The touchdown zone and the mid-point, if the runway is intended for Category II operations.
- The touchdown zone, mid-point and stop-end, if the runway is intended for Category III operations.
RVR information is included in local routine reports, local special reports, METAR and SPECI.
- ICAO Annex 3: Meteorological Service for International Air Navigation
- ICAO Doc 9328: Manual of Runway Visual Range Observing and Reporting Practices
- JAR-OPS 1, especially paragraph 1.430, Appendix 1 and related IEM. ICAO Annex 6 (Operation of Aircraft) especially Chapter 4 and Appendix 2.