This is the Oakly class destroyer. This ship is based on the Fletcher class destroyer in real life. I have made an entire fleet of different ships ranging from aircraft carriers to destroyers. This is the smallest ship in the fleet and is the work horse of my navy. Unlike the battleship this ship is mass produced escorting larger capital ships against threats like air raids and submarines. This ship has a full interior

To fire the main guns use this command /summon Fireball ~ ~0 ~ {ExplosionPower:0,direction:[0.0,0.0,0.0]}
To determine the power of the weapon you need to look at its caliber like this destroyer has 5 inch guns so a power of 5. If you are unsure of the caliber it will be listed in the ships specifications.
Torpedoes and bombs have a set power see below for exact numbers.

If you wish to make your own ship look at each of these pages to find the rules of each ship type.

Role
Asw(Anti Submarine Warfare)
Anti Aircraft support
Patrol
Convoy escort
Capital ship escort

Specifications
Length 118 Blocks
Beam(width)21 Blocks
Total displacement 26,380 Blocks
Engine power 2 powerplants containing 1,050 redstone blocks
Armor
main belt 2 blocks
main deck 2 blocks
internal deck 1 block
Torpedo belt 3 blocks
Turret armor 1-2 blocks
Armarment
5x1 5inch/127mm duel purpose gun
2x5 Torpedo launchers
7 headgehog asw mortars
6 K-gun depth charge launchers
14 40mm bofors
40 20mm oerlikon

Armament specific info
5in duel purpose guns
These guns can fire at long ranges at ships and aircraft
torpedo launchers
This can equip anti ship non guided torpedoes (power 20)
or asw homing torpedoes (power 10)

Destroyer type rules
Smallest ship type no longer than 120 blocks
thinly armored ship no more than 3 blocks of armor
Can only mount 5 inch guns or less for main armament
no asw,aa gun, and torpedo system restrictions