Background
In accordance with proposed changes to ICAO Annex 3, Amendment 74, the definition for CAVOK will change from 0001 UTC on Wednesday 5 November 2008.
The new definition will be:
1. No cloud below 5000 ft above airfield level (or minimum sector altitude, whichever is higher)
2. No CB or TCU at any height
3. Visibility 10 km or more
4. No significant weather
