re·con·nais·sance 
/rɪˈkɑ:nəzəns/ noun
plural re·con·nais·sanc·es /rɪˈkɑ:nəzəns/ noun : military activity in which soldiers, airplanes, etc., are sent to find out information about an enemy [noncount] ▪ There are two helicopters available for reconnaissance. ▪ reconnaissance missions/aircraft [count] ▪ They did/conducted a reconnaissance of the enemy's position.
