Visibility 6 : The greatest distance at which objects can be seen and identified from the cockpit of an aircraft during flight. Visibility can be reduced by cloud, smoke and darkness
Dr. Robert Stacey (compilor), European Glossary of Wildfire Terminology (Covering areas of wildfire environment, fire behaviour, fuel, topography, weather, wildfire suppression operations, safety, incident command, tactics, cartography and map reading, equipment, aerial operations, wildfire preparation, prevention and recovery, prevention and detection, fire investigation and restoration), EUFOFINET (European Forest Fire Networks) Project, Northumberland Fire and Rescue Service, Northumberland UK 2012 (1st Ed.). http://www.fire.uni-freiburg.de/literature/EUFOFIN ET-Fire-Glossary.pdf, (For Fr - Brit) {808}