Water Cannon

Water Cannon
Block Type	310 Weaponry
Mass	1.5
Friction	0.6
Drag	0.2
Dimensions	2 x 1 x 1
Interactivity
Action	Shoot
Default Key	Y
Weaknesses
Breaks	No
Freezes	No
Burns	No
Break Forces
Bottom	Infinite Vulnerable to Tick Damage
Top	-
ID	56
Version Introduced	v0.11

The Water Cannon is a machine block. It can be used to extinguish burning blocks and fires (such as in the stage Sacred Flame), but is more commonly used for propulsion.

Settings

Parameter	Default Value	Range
Shoot Spew and shoot out water.	[Y]	Keys
Hold to Shoot When enabled, water spews out only when the button is press and held.	False	Boolean
Power Adjust how powerful water spews out.	x1.00	x0.10 - x1.50 (x4.00 By copying and pasting Shrapnel Cannon power )

Usage

The most obvious use of this block is for extinguishing fires. However, as a fire suppression system, it's only useful if a minimum of flammable blocks have been used and proper care has been taken to separate them, as fire spreads quickly and works fast.

In sufficient quantities, it can also be used for pushing objects. This is useful for crowd control (i.e. pushing away pesky soldiers).

It also has significant, constant recoil force, and no time limit.
As the sections below outline, this characteristic means it is far more common in practice for this block to be used for propulsion of aircraft and other vehicles.
Its advantages include:

• It delivers a constant amount of thrust at all speeds
• It is immune to all forms of damage (and, in fact, can use fire to its advantage)
• It has an indestructible connection
• Water cannons ignore collisions with other water cannons. This is especially useful in vanilla use cases, where power is limited - this makes it the most space-efficient propulsion method.

Steam Cannon

By holding a flame to a water cannon (e.g. with Torches, Flaming Balls, Flamethrowers, or burning blocks), it will fire steam instead of water and deliver eight times the recoil force.

For high-performance vanilla aircraft, the steam cannon is a common propulsion method due to its power and the aforementioned ability to place multiple cannons in the same position. The torch is the common block of choice as it doesn't have a fuel limit; however, care must be taken to ensure it isn't put out by the steam.
It is worth noting that the water cannon is a heavy block, and stacking a lot of them will significantly affect your machine.

There is one downside, though: as the steam plume has collision, flying into the steam plume will blow parts off of your plane or even pull it in the wrong direction. This is actually incredibly easy, as steam does not inherit velocity from the cannon. This makes it an incredibly risky option for VTOL purposes.

Steam is also much more effective at pushing objects than water.

Nive

By using NoBounds, it is possible to set water cannons to a negative value. This causes the block to generate thrust without generating water or steam particles.

This makes it the block of choice for propelling modded machines as water cannon does not burn and has an indestructible joint, allowing it to have a high power ceiling that would otherwise break Flying Blocks.

The recoil force will be in the opposite direction to a positive water cannon. Additionally, the formulas for Power < 1.0 is used when calculating their thrust.

Nive is short for Negative Water Cannon. Nive is not associated with other negative value blocks as Negative Water Cannons are the most common type of negative blocks to be used.

Recoil Force Formula

Water Cannon/Nive

The exact recoil force delivered by the water cannon is defined by this piecewise function:

$force = \begin{cases} power\times 10 , & \text{if }power <\text{1.0} \\ power\times 14 -4, & \text{otherwise} \end{cases}$

To suspend a block or creation in air, gravity must be accounted for:

$power = \begin{cases} mass \times 3.281, & \text{if }power <\text{1.0} \\ mass \times 2.34358 + 0.285714, & \text{otherwise} \end{cases}$

Note that the actual power required to suspend something in the air might be slightly different to this equation because of floating-point imprecision.

Steam Cannon

The formula for steam cannon is almost identical to the formula for regular water cannon, just that the output force is multiplied by eight.

$force = \begin{cases} power\times 80 , & \text{if }power <\text{1.0} \\ power\times 112 - 32, & \text{otherwise} \end{cases}$

To suspend a block or creation in air, gravity must be accounted for:

$power = \begin{cases} mass \times 0.410125, & \text{if }power <\text{1.0} \\ mass \times 0.292946 + 0.285714, & \text{otherwise} \end{cases}$

Technology

The pushing power of steam is high enough that it can be used to build actual piston Engines. However, the plume lags behind the machine at speed, which only makes it useful (and safe) for very slow or stationary machines.

Negative water cannons find use in high-power Recoil Suppression systems, either alone to counter recoil in autocannons or as part of more complex systems like the Proportional Response/DL system. They can also be used to directly move elements of mechanical engines instead of push them.

Water cannons are a classic Overflow block; in this condition they generate no water and generate a strong resistive force.

Gallery

A small steam cannon setup.