Unless you can find a rule saying you can, you cannot.
Unless I have missed something, no you may not fire a direct fire siege weapon as an indirect fire siege weapon as nothing says you can.
Firing a cannon is not like firing a catapult.
It is but isn't irl cannons have been used as howitzers throughout history. And the bombard description says it can be used as both...i just can't find anything that states otherwise.
This isn't real life. It is a game. With rules. Arguing that it functions differently in real life has no meaning or affect on the rules of the game.
Bombards include in their rules that they can be fired either directly or indirectly. Cannons do not, and therefore cannot.
If this is an issue for you, I suggest selling the cannons and buying bombards.
It is but isn't irl cannons have been used as howitzers throughout history. And the bombard description says it can be used as both...i just can't find anything that states otherwise.
Often special measures have to be taken to do so. Sometimes pits had to be dug to allow the trail to sit low enough. Sometimes ramps were made to allow enough elevation. Since the gunsights aren't designed to accomodate this situation, accuracy suffers, often greatly.
These measure would all be GM fiat to allow the use of a direct fire weapon as an improvised indirect fire weapon.
I've got similar issues with alchemists using longbows and the Explosive Missile discovery or launching crossbows. I want to make a mortar out of them but existing rules don't seem to support it.
Why would firing a bow work like a mortar? Why would that even be necessary?
Is it because the character has a low(er) BAB and dex and is more likely to miss using the normal rules for firing a bow then if he gets to use indirect fire attack which uses int/Know (Eng.) and BAB?
If so, even that doesn't help you because rule for indirect fire says it hits the square, not the creature. And explosive missile doesn't work unless it hits the creature.
It says target, actually. Nothing about creatures in the description, so I assume a square is fine.
"When the infused ammunition hits its target, it deals damage normally and detonates as if the alchemist had thrown the bomb at the target. If the explosive missile misses, it does not detonate."
I'd like to be able to lob explosive arrows over a wall or intervening barrier to target a square if it seemed appropriate. I've got an engineering corps in one of the games I'm running that could make good use of that.
It says target, actually. Nothing about creatures in the description, so I assume a square is fine.
"When the infused ammunition hits its target, it deals damage normally and detonates as if the alchemist had thrown the bomb at the target. If the explosive missile misses, it does not detonate."
I'd like to be able to lob explosive arrows over a wall or intervening barrier to target a square if it seemed appropriate. I've got an engineering corps in one of the games I'm running that could make good use of that.
You have a point.
But, then I shall point out this:
Bomb (Su): In addition to magical extracts, alchemists are adept at swiftly mixing various volatile chemicals and infusing them with their magical reserves to create powerful bombs that they can hurl at their enemies. An alchemist can use a number of bombs each day equal to his class level + his Intelligence modifier. Bombs are unstable, and if not used in the round they are created, they degrade and become inert—their method of creation prevents large volumes of explosive material from being created and stored. In order to create a bomb, the alchemist must use a small vial containing an ounce of liquid catalyst—the alchemist can create this liquid catalyst from small amounts of chemicals from an alchemy lab, and these supplies can be readily refilled in the same manner as a spellcaster's component pouch. Most alchemists create a number of catalyst vials at the start of the day equal to the total number of bombs they can create in that day—once created, a catalyst vial remains usable by the alchemist for years.
Drawing the components of, creating, and throwing a bomb requires a standard action that provokes an attack of opportunity. Thrown bombs have a range of 20 feet and use the Throw Splash Weapon special attack. Bombs are considered weapons and can be selected using feats such as Point-Blank Shot and Weapon Focus. On a direct hit, an alchemist's bomb inflicts 1d6 points of fire damage + additional damage equal to the alchemist's Intelligence modifier. The damage of an alchemist's bomb increases by 1d6 points at every odd-numbered alchemist level (this bonus damage is not multiplied on a critical hit or by using feats such as Vital Strike). Splash damage from an alchemist bomb is always equal to the bomb's minimum damage (so if the bomb would deal 2d6+4 points of fire damage on a direct hit, its splash damage would be 6 points of fire damage). Those caught in the splash damage can attempt a Reflex save for half damage. The DC of this save is equal to 10 + 1/2 the alchemist's level + the alchemist's Intelligence modifier.
So, using this method it does full damage to the square only (not the creatures in the square, as they're a different target), and minimum damage to everyone in the splash range.
House rule: cannon can be fired either directly or indirectly. Bam, done.
For extra realism, impose a substantial penalty on firing them indirectly.
Yes, but this is the rules forum, not the house rules forum.
Yes, but it can only be used in the required mode while mounted on the vehicle.
Example: A standard ship of the line can't use a bombardment mortar because they'll set their own rigging on fire. If you mounted a hybrid weapon that can be used as a direct fire weapon OR an indirect fire weapon, you can mount it but if you use it as indirect fire, you're still going to set your own rigging on fire or otherwise damage it with the blast. You need a specialized bomb ketch that uses chain for certain vulnerable parts of the rigging and you still can't use indirect fire under full sail.
I don't recall sailing ships listing that they can only use direct fire weapons? Can you point me to that?
In fact, what I remember (and I'm currently playing Skull and Shackles, but don't often bother with siege weapons) is that both ballista and catapults are common armaments, the first being direct and the latter being indirect.
Medieval siege weapons were only useful indirectly if you weren't actually bothered about what you hit. That's why they lobbed incendiaries and biological weapons into towns rather than (for example) trying to drop ammunition onto defenders on towers or walls.
There is no reason that a medieval cannon/bombard (they are basically the same creature) couldn't be used to lob ammunition indirectly, but it would have been a waste of a valuable weapon. Given the cost of cannon and their crew and engineers and the slowness of their rate of fire (two shots a day wasn't unusual) using them to throw balls blindly into a town would have been like buying a main battle tank and using it to tow the supplies. The cannon's great advantage was the power of its direct fire in reducing castle walls, with smaller cannon useful to annoy and demoralise troops on the battlefield when they were out of bow/crossbow range.
I don't recall sailing ships listing that they can only use direct fire weapons? Can you point me to that?
In fact, what I remember (and I'm currently playing Skull and Shackles, but don't often bother with siege weapons) is that both ballista and catapults are common armaments, the first being direct and the latter being indirect.
Ultimate Combat: Vehicles, Water Vehicles, Sailing Ship; Weapons stat block:
"Up to 20 large direct fire siege engines, in banks of 10 on the port and starboard side, or up to 6 Huge direct fire siege engines in banks of 3 on the port and starboard side. The siege engines may only be fired out the sides of the ship they are positioned on. They cannot be swiveled to fire towards the foraard or aft sides of the ship"Skulls and shackles player guide: as above but now including:
" in addition up to 2 large or 1 huge direct fire or indirect fire siege engines may be placed in both the forecastle and sterncastle of the ship. Those siege engines can be swiveled to fire out the sides of the ship or the forward or aft, depending on their position"Answer your question?
Indeed it does, and as I thought you can use both (though there is a restriction on placement/number) which I recalled as well.