what is the relationship between CEP and hit probability?

[hanzawa1991]

In CMO, what is the relationship between CEP and hit probability? It seems that CEP is defined as the radius within which there is a 50% chance of the munition landing. Does hit probability then refer to the likelihood of striking the target once the munition is within this range?

[blu3s]

Indicates the reliability of the weapon, as state in the DB Viewer, so a Weapon with 80% of Reliability will detonate in average 80 times and 20 will malfunction from 100 launchs.

[Gunner98]

Generally speaking CEP is used when engaging with indirect guided (missile or PGM) weapons. The term used for indirect ballistic fire (guns, mortars and rockets), anything without guidance is PER (Probable Error in Range). Hit Probability (HP) is usually used in direct fire weapons, unguided or guided.

So an ATGM with an HP or .9 would not have a CEP as it is predicted to actually hit the specific target it is aimed at 90% of the time.

An IRBM or something with a CEP of 100meters is not actually aimed at anything. It is guided to hit a point target, a piece of ground which may or may not have something located near it (this is where you need ISR). So 50% of IRBMs fired will land within 100 meters of that geographic point, and there are further calculations for how far away the other 50% will land which I cannot remember at the moment - something like 28% will land at 2xCEP, 13% at 4x CEP etc

Not exactly sure how the game uses the terms but from my memory of ballistics this is what is used in real life, so I assume the game is modeled on it.