Common Sense Ships and Airships

<div class='cover-header'>Common Sense Ships and Airships</div>

<div class='cover-footer'> A 5e resource for sea and air ships and combat</div>

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# Common Sense
# Ships and Airships
___
## *Ship Classes*

The D&D resource Ghosts of Saltmarsh introduces new rules for ship-based adventures. The rules are not fleshed out in many places—sketches of what could be rules—and the few example ships don't generalize well or seem based in principles DMs can use to design enemy ships for encounters.

The rules beg a few questions.

* How does flooding on a ship start? How is it handled? 
* How are damaged ships repaired? How long does it take? What does it cost? (The player's handbook rules (1 HP per day in dry dock) are are unrealistic (ships do some repairs at sea) and not conducive to a sea-based campaign.
* When do fires start? What controls fire spreading and how are they put out?
* How is damage split between the ship sections and crew from an area effect attack? 
* Why do all the ships' sails (regardless of the fact that some have 5 times as many) have the same HP?
* What section/subsystem in an airship provides buoyancy and what is the effect of increasing damage?
* Why are common actions for ships like patching and pitching the hull, fighting fires, furling/unfurling sails, weighing/dropping anchor, grappling, boarding, small arms fire, etc. not listed as ship actions?
* Why is movement a ship action? Movement is separate from actions in the rest of D&D 5e.
* Why don't the number of actions a ship can take depend on its size?

The Ghosts of Saltmarsh rules are more of a sketch, requiring DMs to make up extensive house rules to handle common situations. Also, the concept of "ship  actions" separates players from ships.

Accordingly, this resource guide defines ***ship size classes***, which automatically scale ship features according to their size, making stat blocks consistent and simple to generate. In this rule set, ship actions are replaced by crew group actions and **players/NPC ship officers can use actions/bonus actions to give orders to crew groups**, maintaining the usual initiative-based flow.

These rules integrate ship actions seamlessly and the generalized scaling of ships by classes maintains the "keep it simple" spirit of 5e.

## Sections
1. Ship Size Classes and Stats
2. Ship Features and Actions
3. Airship Classes and stats
4. Airship Features and Actions

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## 1. Ship Size Classes

Ships and airships are grouped into classes based on their size. Ships start from rowboats at class 0 to very large sailing ships and ships-of-the-line at class 5. Airships vary from class 1 to class 4.

| Ship Class | Examples |
|:--:|:--:|
| 0 | rowboat, gondola |
| 1 | skiff, sailboat, keelboat, canal barge |
| 2 | sloop, patrol boat, yacht |
| 3 | sailing ship, caravel |
| 4 | carrack, galley |
| 5 | galleon, frigate |

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### Sea Ship Stats by Class

| Feature |Class 0 | Class 1 | Class 2  | Class 3 | Class 4 | Class 5 |
|:--:|:--:|:--:|:--:|:--:|:--:|:--:|
| Strength modifier | 0 | +1 | +2 | +3 | +4 | +5 |
| Constitution modifier | 0 | +1 | +2 | +3 | +4 | +5 |
| Dexterity modifier | +5 | +4 | +3 | +2 | +1 | 0 |
| Crew groups (actions) | 0 | 1 | 2 | 3 | 4 | 5 |
| Weapon placements (hardpoints) | 0 | 1 | 2 | 3 | 4 | 5 |
| Max turn angle per round | 90 deg| 90 deg | 45 deg | 45 deg | 30 deg | 30 deg |
| Crew size (full/skeleton) | 1/0 | 6/3 | 10/5 | 20/10 | 60/30 | 100/50 |
|  Passengers (ferried/berthed)  | 8/– | 12/– | 32/16 | 40/20 | 80/40 | 120/60 |
| Max sailing speed (ft.) <br> (0-45/60-90/120-150 deg to wind) | – | 30/20/10 | 40/30/10 | 60/45/15 | 75/60/20 | 100/75/25 |
| Galley rowing speed | 15 ft. | 20 ft. | 20 ft. | 20 ft. | 20 ft. |  – |
| Base AC (hull, paddle wheel, weapons) | 15 (10+Dex) | 15 (11+Dex) | 15 (12+Dex) | 15 (13+Dex) | 15 (14+Dex) | 15 (15+Dex) |
| Sails, Crew AC (Base AC - 3) | – | 12 | 12 | 12 |12  |12  |
| Helm, rudder AC (Base AC + 3) | – | 18 | 18 | 18 | 18  | 18 |
| Hull HP (threshold) | 50 | 100 | 200 (5) | 300 (10) | 400 (15) | 500 (20) |
| Sails/mast HP <br> Oars/paddle wheel HP <br> Helm/rudder HP | – | 75 | 100 | 125 | 150 | 200 |
| Ballista / mangonel HP | – | 50 | 50/100 | 50/100 | 50/100 | 50/100 |
| Crew HP (per group) | – | – | 100 | 100 | 100 | 100 |

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## Ship Features and Actions

##### Ship Strength and Constitution
Vessels have Strength and Constituion modifiers equal to their class and a number of hardpoints (ship weapons) and crew actions per round equal to the class.

Strength is a ship's ability to escape grapples from sea monsters, grappling lines, and whirlpools, or tug other ships.

Constitution affects a ships ability to save against attacks requiring constitution saves.

*Ability scores and features can vary based on the ship design, but should include tradeoffs/costs.*

##### Dexterity and AC

A ship’s size and loading determine its Dex modifier. The Dex modifier affects a ship’s base AC, turn rate, and is used for piloting skill checks (+ pilot’s proficiency) and Dex saving throws against attacks. Subsystems have their own ACs derived from the base AC and separate HP pools. Damage to subsystems affects speed, buoyancy, and maneuverability.

##### Orders = Actions/Bonus actions
In initiative, ship officers (PCs or NPCs) may use an action or bonus action (or both) to give an order to a crew group.

Crew are divided into a number of groups up to a ship's class. Each group has around eight to ten crew. The largest ships have 5 crew groups that can take actions.

A crew group's action is resolved immediately following their commanding officer's turn.

##### Example combat flow
A ship's officer (player character or NPC) readies an action to relay any order they receive from the captain.

As an action on her turn, the captain orders the pilot at the helm to, "change course from north to due east at maximum speed." As a bonus action she orders her officers to, "attack the nearest ship with everything we've got."

As long as one trained crew member is at the helm (or the captain) and the ship's helm/rudder are functional, the ship then turns its maximum angle. In this case, we have a ship of size 3, so it turns 45 degrees. The distance it travels will depend on whether the deck hands responsible actually succeed in trimming the sails (which could require a skill check in adverse weather). If they fail, or are directed to another task, there is a movement penalty.

The officer's held action triggers and he uses his prerogative to order a crew group to fire their two ballistae at the enemy ship's helm. As a bonus action he orders a second group to fire a mangonel at the enemy ship's helm.

The mangonel and two ballista attacks are resolved (2 NPC crew actions).

Next up is the third ship officer (PC) in charge of the ship's deck hands. The officer orders them to engage in close quarter's combat, and casts a fireball spell at the enemy ship's sails.

The deck hands draw pistols and fire at the crew of the enemy ship. Since the deck hands are not trimming the sails this turn, maximum movement is reduced by 10 ft.

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##### Enemy ship actions
Enemy ship officers and their crews take actions in the iniatitive order, just like PCs and NPCs, such that action may alternate between allies and foes during a combat round, as per usual combat.

Likewise, enemy ship officers can activate a ship's legendary action after any player's turn.

##### Small ships or no crew = no crew actions

For ships small enough that there are no NPC crew groups, actions are per the usual combat flow. Player characters can ready actions, trim sails, load/assist to load and fire ballistas, etc. There are no ship "actions" unless there are NPC crews.

##### Ship weapon placements
A ship can have a maximum number of weapons equal to its size. If you are using ships with a large number of cannons, they must be grouped into batteries and resolved in a number of actions no greater than the ship's class in order to maintain game flow. E.g. a group fires two ballistae with one attack roll.

##### Crew AC and HP

Crew AC is 12. They are treated as a swarm with 100 HP, with *vulnerability to area effect attacks*. Crew on deck can be targeted.

When a crew group's HP falls below half of max, they have disadvantage on skill checks (not attack rolls) and deal 1/2 damage in close quarters combat.

When hull HP is below half of max, 1/2 damage from each attack is added additionally to one crew group below decks.

##### Crew skill Checks

Crew may need to perform skill checks both in- and out of combat initiative. *For small ships, 3 PCs constitute a crew group.* (Small ship PC crews can operate one ballista, fire a mangonel every other turn and resolve combat individually.)

For routine activities such as trimming sails, rowing, or weighing anchors the skill DC is 5. Basic crews have proficiency +4 (per GoS). Skilled crews have higher proficiency for skill checks, though they demand more pay.

The following condition affect the skill check DC. Other conditions or effects may apply at the DMs discretion such as a deck being overcrowded, severe cold, etc..

A critical fail on a crew skill check may result in an equipment failure or hazard, such as an unsecured line lashing across the deck or wildly swinging sail boom, necessitating Dex saving throws from crew or PCs on deck, or potentially a sailor going overboard or being maimed, which could affect morale and loyalty.

##### Loyalty

Loyalty affects a crew's proficiency. (They try harder when they care.)

| Loyalty | Proficiency |
|:--:|:--:|
| < 5 | -2 | 
| 5–14 | -1 |
| 10–14 | 0 |
| 16–20 | +1 |

As a DM you can choose to ignore crew skill checks until there is something that makes a skill check more difficult, such as trimming sails during a tacking movement or in high seas.

##### Movement and Actions
In initiative, the ship's captain/pilot/helmsman can attempt to make movement in addition to any crew actions.

##### Crew Actions

Crew actions (detailed in a succeeding section) include 
* trim/unfurling/furling sails
* loading/firing weapons
* dropping/weighing anchor
* ship weapon attacks
* take cover (dodge)
* put out fire
* shoring hull breaches and bailing water
* lookout for enemies
* close quarters combat
* grappling lines/cutting lines
* deploy/recover longboat
* boarding
* mooring/docking

##### Turning and Size
Long ships are harder to turn, requiring up to 2 or 3 rounds to make a 90 degree turn.

##### AC and Size
Larger ships have thicker hulls and higher base AC, which is offset by the Dex bonus of smaller ships, such that all ships and ship sections begin with AC independent of ship class

##### Crew Size
A skeleton crew can operate a ship, but cannot keep up with maintenance tasks or respond as well to emergencies. A skeleton screw has no proficiency bonus for tasks such as putting out fires, patching and shoring the hull, repairs, bailing the hold, maintenance checks, etc.

##### Assisting the Crew
If one or more players characters with a suitably useful ability or skill (such as Str, Dex, or Int) uses their action to assist a crew, the DM may grant advantage to the group, or remove a disadvantage due to low group HP.

Untrained PCs/NPCs working without crew have no proficiency and disadvantage on crew skill checks.

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##### Passengers
The ship class table shows how many passengers can berth (stay overnight) on a ship. A ship can ferry two or three times as may passengers over a short distance. As a rule of thumb, budget 500 lbs. per berthing passenger and crew member for their weight, trunk and required food.

##### Sailing speed
Sailing speed depends on ship size, wind speed, direction and crew skill.

Due to the interference of bow and stern waves, longer ships have less drag and sail faster.

For optimal sailing, the angle of the sails has to be adjusted when the ship changes direction. This is called "trimming" the sails. It only has to be done when changing direction.

Tacking means changing direction while sailing into the wind. This is tricky and dangerous. Ship speed drops dramatically, and the ship lists suddenly in the opposite direction.

##### Rowing Speed

Only ships with a rowing galley or small ships with oars have a rowing speed. Rowing speed is affected by crew health, wind, and waves.

##### Targeting ships
When a ship is attacked, the default target is the hull. The attack can also target the sails/mast, helm/rudder, or a weapon system. Each has its own AC and HP.

If the attack is an area affect requiring a save, the ship attempts a save (e.g. Dex save). If the area effect includes multiple systems such as the helm, sails and deck (hull), each system takes damage.

##### Hull AC and HP
If an enemy does not target a specific ship section, the target is the hull. **Hulls are resistant to fire damage** because they are wet.

The AC for the hull is determined by the ship's size and Dex modifier.

The hull keeps the ship up. If it is reduced to 0 HP or the hold reaches flood stage 5, the ship is sinking.

When a hull is severely damaged, weapon attacks pass some damage onto crew or passengers below decks. When a hull is sufficiently damaged, if a portion of the crew does not take the "shore/bail" action, the ship will take on water and add one flood level, suffering a penalty to Dex (AC), and speed and increasing the DC for the "shore/bail" skill check.

##### Hull Damage threshold
Damage below the damage threshold has no effect. Damage above threshold debits from HP as usual. Adding an armor layer (max 2 layers) increases damage threshold by +5 HP and reduces passenger capacity by 25% of max for each layer, up to a maximum damage threshold of 20.

##### Sails and Masts AC and HP
Sails and masts share a common HP pool.

**Sails have AC 12**  and are *resistant to piercing damage* as bullets, arrows, spears and ballista bolts simply pass through leaving only a small hole.

**Masts have AC 18** and have no damage resistances.

Sail/mast damage has effects on ship speed.
| Sail/Mast Damage | Effect |
|:--:|:--:|
| <50% HP | -10 ft. or half speed, whichever is higher, <br> +2 to sail trimming skill check DC |
| <25% HP | half speed, Dex and AC reduce by 2 |
| 0 HP | sails/masts destroyed, no sailing speed |

##### Helm and Rudder AC and HP
The helm, including any wheel house, and the rudder are difficult to target and have an AC of 18. They share a common HP pool. When this pool reaches zero, the ship cannot be steered, except by oars if there is a rowing galley, and the ship Dexterity decreases by 4, which reduces its hull AC correspondingly.

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##### Ship weapons AC and HP

Ship weapons have the same AC as the hull. Each of the ship weapons systems has its own HP pool. When a weapon is below 25% of max HP it has *disadvantage on attack rolls*.

##### Fire

Ship sections that take fire damage must succeed on a Con saving throw of DC 5 or 1/2 of the fire damage (whichever is higher) or catch fire. Wet sections have advantage on the save.

Fires begin at intensity equal to fire damage divided by 10.

Each round roll 1d4 to determine the fire behavior. When a fire reaches intensity of 5, make another Con save to see if the fire spreads to another section. In the new section the fire begins at intensity 1.

| Condition | 1 | 2 | 3 | 4 |
|:--:|:--:|:--|:--:|:--:|
| Wet (rain or stormy seas) | +1 intensity | no change | -1 intensity |  -1 intensity |
| Dry (no rain, calm seas) | +1 intensity | +1 intensity | no change | -1 intensity |

If a crew group is successful in a *put out fire* action the intensity decreases by 1. Multiple groups can take the put out fire action.

**At the beginning of a new round fire in a section/system does 1d6 damage per level of intensity.**

##### Flooding

When the hull takes damage and ends up below 25% of max hull HP, the ship attempts a Con saving throw of DC 8 or 1/2 of damage taken (whichever is greater). On a fail, the ship gains the *flooding* condition.

If a ship begins a round in the flooding condition and ends the round without a crew group making a successful shoring/bailing skill check, the ship gains an additional flooding stage. Once a group succeeds on a shoring/bailing skill check, the ship is no longer in the *flooding* condition. Additional successful shoring/bailing skill checks reduce the flood stage by 1.

Flooding is aggregate. If a ship fails two flooding Con saves in a round, the flooding stage can increase by two in the next round. If on group succeeds in shoring/bailing, flooding increases by 1. If both groups succeed, flood stage does not increase.

As flooding increases, the crew has to brace shoring timbers against hull breaches in increasingly deeper water in the hold and the DC for a successful shoring/bailing skill check increases.

Flooding decreases the ship Dex modifier, which reduces the AC of each ship section correspondingly.

The base DC for shoring/bailing can be affected by rough seas. **At flood stage 5, the ship sinks 5 ft./round.**

| Flood stage | Shoring/bailing base DC | Ship Dex change |
|:--:|:--:|:--:|
| 0 | 8 | — |
| 1 | 10 | -1 |
| 2 | 12 | -2 |
| 3 | 14 | -3 |
| 4 | 16 | -4 |
| 5 | 18 | -5 |

## Crew Actions

| Action | DC | Success | Fail | Critical Fail (optional) |
|:--:|:--:|:--:|:--:|:--:|:--:|
| **Trim, furl, or unfurl sails** | 5 + mods | — | -10 ft. sailing speed or half sailing speed (whichever is higher) | roll 1d4 for mishap: <br> (1) PC or NPC DC 12 Dex save or overboard; prone on save  <br> (2) 1d10 damage to PC or (3) NPC <br> (4) 1d10 damage to sails/masts |
| **Take cover** (dodge action) | — |— | — | — |
| **Load, aim, fire ballista** (2x/group) | — | —| — |— |
| **Load, aim, fire mangonel** | — | — | — | — |
| **Drop anchor** | 5 + mods | anchored | not anchored | 1d10 damage to crew |
| **Weight (raise) anchor** | 5 + mods | anchored | not anchored | 1d10 damage to crew |
| **Put out fire** | DC 5 + 5 if sails + intensity | intensity decreases 1 for each group that succeeds | 50% chance intensity increases, 25% chance decreases | 1d10 damage to crew |

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## Airships
Airships differ from sea ships in a few key ways.
* Due to airship complexity, there are no class 0 airships (too small).
* Airships require a magical source of bouyancy in the hull to stay in the air, such as an Aetherium core (1/class), soarwood, or magical artifact or construct.
* Rather than flooding, airship hull damage causes the ship to lose buoyancy, meaning the ship struggles to gain altitude and eventually begins to go down.
* Airships have no keel so they can't sail into the wind.  An airship can adjust its altitude to try to find winds in the direction it is going, but this is not always possible. Another source of propulsion (propellers, elemental, gust spell construct, etc.) is generally required if a ship is not traveling in the direction of the prevailing winds.
* Airships do not have the bow/stern wave interference of sailing ships so ship speed is not dependent on size.
* Airships have lower damage threshold due to lighter construction. Adding armor to increase damage threshold will reduce cargo and passenger capacity.
* Airships have +1 Dex and -1 Str and Con versus ships of similar size, which means +1 AC for airships—hard to hit things that can move up and down, too!
* Airship weapons are of lighter construction and have less HP and passenger capacity.

## Ship repairs

### Repairs at port

Ships can be repaired and improved at most harbors. Repairs will take 1 day for every 50 hp missing and cost 2 gp per hp repaired + 100 gp for every 40hp of rigging. Some harbors could be more or less expensive.

Enhancements and upgrades may be ordered and installed during this same time period.

### Repairs at sea (temp HP)

After taking damage, crew groups can spend 8 hours repairing their respective damaged ship systems if they have supplies in the form of timbers, spare sails and rigging. One crew group working on a ship system for one day, with sufficient tools and supplies, can add temporary hit points up to 25% of its max HP. The current HP and temporary HP total must be less than the max HP for the system.

##### Repairs at sea example

After a battle, a class 2 ship sustained 120 HP of damage to the hull, 20 HP damage to the helm, and 80 HP damage to the sails and masts.

The ship has 2 crews. On the first eight hours one crew group works to repair the hull while the other takes a long rest. Then the second crew group replaces damaged sails and repairs the masts.

| System | Max HP |HP after battle | Temp HP | Current total HP |
|:--:|:--:|:--:|:--:|:--:|:--:|
| Hull | 200 | 80 | 200 x 25% = 50 | 80+50 temp = 130 |
| Sails/ <br> masts | 100 | 20 |100 x 25% = 25 | 20+25 temp = 55 | 
| Helm | 100 | 80 | 100 x 25% = 25 (limit 20) | 80+20 temp = 100 |

## Submersibles

Submarines are like airships except:
* damage threshold is 5 * class.
* the submersible can be class 0.
* at maximum hull mishaps the submersible sinks
* crew close quarters attacks against targets outside the submersible are not possible while submerged.
* no disadvantage to stealth while paddling/turning a screw
* hull mishap is technically flooding, but the effect is reduced lift/buoyancy similar to airships. The crew can stops leaks, but  cannot bail unless surfaced. (The spell *create or destroy water* is useful.)

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## Airship Stats Table 
| Feature | Class 1 | Class 2  | Class 3 | Class 4 | Class 5 |
|:--:|:--:|:--:|:--:|:--:|:--:|
| Strength modifier | 0 | +1 | +2 | +3 | +4 |
| Constitution modifier | 0 | +1 | +2 | +3 | +4 |
| Dexterity modifier | +5 | +4 | +3 | +2 | +1 |
| Crew groups (actions) | 1 | 2 | 3 | 4 | 5 |
| Weapon placements (hardpoints) | 1 | 2 | 3 | 4 | 5 |
| Max turn angle per round | 90 deg | 45 deg | 45 deg | 30 deg | 30 deg |
| Crew size (full/skeleton) | 4/2 | 8/4 | 16/8 | 40/20 | 80/40 |
|  Passengers (ferried/berthed)  | 8/– | 12/– | 32/16 | 40/20 | 80/40 |
| Max sailing speed (ft.) <br> (0-60/90/>90 deg to wind) | 100/75/0 | 100/75/0 | 100/75/0 | 100/75/0 | 100/75/0 |
| Base AC (hull, propellers, weapons) | 16 (11+Dex) | 16 (12+Dex) | 16 (13+Dex) | 16 (14+Dex) | 16 (15+Dex) |
| Propulsion (varies up to 60 ft)  | 60 | 60 | 60 | 60 | 60 | 
| Sails, Crew AC (Base AC - 3) | 13 | 13 | 13 |13  |13  |
| Helm, rudder AC (Base AC + 3) |  19 | 19 | 19 | 19  | 19 |
| Hull HP (threshold) | 80 | 150 (5) | 250 (10) | 320 (15) | 400 (20) |
| Sails/mast HP <br> Propellers HP <br> Helm/rudder HP |  60 | 75 | 100 | 125 | 150 |
| Ballista / mangonel HP |  40 | 40/80 | 40/80 | 40/80 | 40/80 |
| Crew HP (per group) | 80 | 80 | 80 | 80 | 80 |
| Crew close quarters attack damage | 6d6 | 6d6 | 6d6 | 6d6 | 6d6 |

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### FAQs
Ask me questions and get answers at [adventure@authordanallen.com](mailto:adventure@authrodanallen.com).

### Change Log
| Date | Change |
|:-|:-|
| 2023.02.11 | Added notes on submersibles |
| 2022.12.30 | clerical fixes |
| 20222.11.18 | Fix off page formating, remove "coming soon ship cost calculator" |
| 2022.03.22 | Adjusted crew size for smaller ships, added disadvantage to stealth for powered sailing for airships |
| 2022.03.14 | Initial draft. All original content. |
| 2022.03.14 | Clerical corrections and added ship repairs |
| 2024.06.22 | Added airship table for convenience. |