Sion Airport PC-6, Pilatus PC-7, Pilatus PC-9 and Pilatus PC-21 as well as helicopters it uses Sion intensively with the fighter jets F/A-18 and F-5 Tiger. It is the home base of the militia pilot unit Fliegerstaffel 19 Swans with F-5E. Sion Airport is, at both ends of the runway, equipped with retractable arresting gear devices (used by the F/A-18 and in case of a problem by the F-5). Because of the redimension of the Swiss Air Force it is planned that the Air Force will leave Sion after 2017 and Sion will be used by civil aviation only, acting only as
Sion, Switzerland recreational space in the municipality increased by and is now about 4.47% of the total area. Of the agricultural land, is used for orchards and vineyards, is fields and grasslands and consists of alpine grazing areas. Since 1980 the amount of agricultural land has decreased by . Over the same time period the amount of forested land has increased by . Rivers and lakes cover in the municipality. Sion has an average of 82.6 days of rain or snow per year and on average receives of precipitation. The wettest month is December during which time Sion receives an average of