your objective is to intercept the enemy contacts, the missiles will only hit the target if you have a positive lock which is displayed on the right hand side on the red rectangle, it will turn green if there's a positive lock. start the radar scanner by pressing the red button close to the lower left corner, your missiles have a total flight time of about 13 seconds. sometimes the enemy will deploy countermeasures and your missile will get destroyed.
collision update added.( if your own missile hits yourself, it's game over.), ALSO PLEASE DO COMMENT.HELP ME MAKE BETTER GAMES.