This page describes the chance of a mine, torpedo, ship anti-missile defense, missile, or plane hitting its target.
Sea mine hit chance The chance of a ship hitting a mine at sea is (mines/(mines+20)). (For example, with 20 mines, the chance of hitting one is 20/40 = 50%) The damage is dependent upon the size of the ship and the spot that the mine hits. (see info Damage). Land mine hit chance The chance of a land unit hitting a land mine is mines/(mines+35). (For example, with 20 mines, the chance of hitting one is 20/55 = 36%). See info Damage to find out how much damage things take from land mines. Note that the chance of land units hitting land mines is divided by 3 if the land units are accompanied by engineers. When moving commodities (civs, mil, shells, etc) or transporting planes, the chance is also dependent upon the weight being moved. First the above chance is checked, and then a chance equal to (weight / 100) is checked. Torpedo hit chance The chance of a torpedo hitting its target is equal to: hitchance = 0.9/(range + 1) where "range" is the range to the target. If the visibility of the ship firing is less than 6, then (5 - visibility) * 0.03 is added to the hit chance. Thus, the base chance of a sub hitting its target (before visibility modification) is: Range Chance 0 90% 1 45% 2 30% 3 22.5% 4 18% 5 15% Ships anti-missile defense If a ship has "anti-missile" defense capabiilty, then it will intercept any marine missiles launched at ships within 1 sector of the ship. Only missiles belonging to a country you are "At War" with will be intercepted. Only ships which are at least 60% efficient will be able to use their anti-missile defenses. The chance of the ship hitting the incoming missile it equal to: hitchance = gun * eff * tfact * 4.5 - (missile "def" value) where gun = the number of guns the ship is allowed to carry eff = the efficiency of the shiip tfact = tech / (tech + 200) where tech is the tech level that the ship was built at Plane and missile hit chance If the target is a sector, then the hit chance is 100%. Otherwise, the following procedure is used to calculate hit chance. The formula for a plane or missile hitting its target depends on the type of the target (ship, plane, land unit) and the "hardtarget" value of the target (which represents how hard that target is to hit). Ship: vis = the visibility of the ship (from 'show ship stats'). For a sub, we set vis = visibility * 4. If the ship is at sea, then: hardtarget = (eff of ship) * (20 + speed/2 - vis) otherwise: hardtarget = (eff of ship) * (20 - vis) The hardtarget of a fleet is the hardtarget if the "easiest" target in the fleet. Land unit: hardtarget = (efficiency) * (10 + (sector defense) * 2 + speed/2 - vis) The hardtarget of an army is the hardtarget of the "easiest" target in the army. Plane: If the plane is in the air (satellite, ICBM), then hardtarget = the "def" value of the plane. otherwise if the plane is on the ground: hardtarget = 0 Once we have calculated the "hardtarget" value of the target, then the chance of a plane or missile hitting its target is equal to: hitchance = acc - hardtarget where acc = (efficiency) * (1 - 0.1 * tfact) * (1 - placc/100) where tfact = (pltech - mintech)/(pltech - mintech/2) where pltech = tech level of plane mintech = min tech level required to build plane and placc = plane accuracy and if the target is a ship and the plane is an ASW plane, then placc = placc - 20 and if the target is a ship and the plane does not have tactical capability placc = placc + 35 Lastly we smooth out the bottom end of the hit chance curve. If hitchance is less than 20, then it is "belled up" using the following curve: hitchance = 5 + 300 / (40 - hitchance). On the other hand, you can just find out the hit chance by pin-bombing or launching a missile--the hit chance is always printed! :-)
See also : fire , launch , bomb , torpedo , Attacking , Damage , Interception , Combat