Ну это малые орудия, стрелявшие 1 снарядом без рассчёта специалистов, а вот большое
Most catapults do not use the normal combat rules for determining the success of their attacks, because typically a catapult is fired not at a particular creature but rather at a specific square on the battlefield. (Ballistae are an exception to this rule, so they use the normal combat rules for determining the success of their attacks.) First, the catapult crew must aim the catapult at a target square. Doing this requires a DC 15 Profession (siege engineer) check by the crew chief (the lead operator of the catapult) and one or more full-round actions taken by the crew of the catapult. Multiple crew members can perform these full-round actions at the same time, reducing the time it takes to aim the catapult. The number of rounds required varies by the weapon. Other crew members can assist this skill check by making a DC 10 Profession (siege engineer) check, as described under Combining Skill Attempts; success on this check this grants the crew chief a +2 bonus on his check.
Next, the catapult must be loaded. As with aiming, loading a catapult requires one or more full-round actions taken by the crew members. As before, multiple crew members can perform these full-round actions at the same time, reducing the time it takes to load the catapult (for example, if the catapult requires four full-round actions to load, a crew of four can load it in a single round). The crew chief must succeed on a DC 15 Profession (siege engineer) check, and at least one member of the crew must succeed on a DC 10 Strength check. Other members of the crew can assist with either of these checks by using the aid another action but must choose which check to aid (that is, the same crew member cannot assist in both rolls). Large or larger creatures load a catapult in half the given time, while Small creatures require twice the given time. Tiny creatures can't load a catapult.
Finally, the crew chief makes a special attack roll to fire the catapult. He rolls 1d20 and adds his base attack bonus, his Intelligence modifier, any penalty for range increments (see Siege Engine Table), and any other modifiers that apply (see the remainder of this sidebar). A square on the battlefield is treated as having AC 15 against a catapult's attack. This attack is a standard action, and the attack roll can't be assisted by the crew. Catapults (other than ballistae) hurl their ammunition in a high arc. A catapult requires vertical clearance equal to half the range to the target to operate, so subterranean races rarely use such devices. Because of this high arc, catapults can strike squares that aren't in line of sight of the crew, though at a -6 penalty on the attack roll.
missIf the attack fails to hit a target that is in line of sight of the crew, and the catapult's next shot targets the same square, the crew chief gains a +2 bonus on his special attack roll. If successive shots at the same square continue to miss, this bonus improves by 2 on every additional attempt to hit the same square, up to a maximum of +10 (after five straight misses).
If the targeted square is not in line of sight but can be seen by an observer communicating with the crew, the bonus for successive attempts against the same target starts at +1 and can improve to as much as +5 (after five straight misses). Each of these attack rolls also takes the -6 penalty that applies because the crew cannot see the target.
If the attack roll succeeds, the catapult's payload hits the target square. A stone deals the indicated damage to any object or character in the square. A load of shot deals only half the indicated damage (see Siege Engine Table) but deals this damage to all creatures or objects in or adjacent to the target square. A creature can attempt a DC 15 Reflex save to avoid the damage from a stone or to reduce the damage from shot by half. Some special forms of ammunition have their own rules (see Magic Siege Engines).
Once a catapult successfully hits the target square, all subsequent shots automatically hit the same square with no attack roll needed, until the catapult is aimed at a different square.