Your Underwater Adventure Awaits
You are standing at the edge of a vast Minecraft ocean, the sun glinting off the deep blue surface. You know there are shipwrecks filled with treasure, ocean monuments guarded by guardians, and vibrant coral reefs waiting below. But diving down with just a door for air is clunky, temporary, and leaves you vulnerable. What you need is a vehicle—a mobile, breathable base that can explore the depths. You need a submarine.
Building a functional submarine in Minecraft is one of the most satisfying engineering projects in the game. It combines redstone mechanics, block placement strategy, and a bit of creative problem-solving to create a vessel that not only looks the part but actually moves, submerges, and provides air. This guide will walk you through two primary methods: a simpler, survival-friendly version using basic principles, and a more advanced, redstone-powered automated sub.
Gathering Your Submarine Building Materials
Before you lay your first block, you will need to collect the right resources. The core concept of any Minecraft submarine revolves around creating an air pocket that you can move. Here is what you will need for a basic, functional model.
Essential Blocks and Items
The beauty of the simple submarine is that it requires no rare materials. You likely have everything already in a mid-game survival world.
– Any solid building blocks (Iron, Concrete, or Stone Bricks are thematic).
– Glass blocks or panes for viewing.
– Doors (Iron or Wooden).
– A bucket of water.
– Signs or Trapdoors (optional, for detailing).
– A Pickaxe and Shovel.
The door is the most critical item. When placed in a 1×2 doorway and then surrounded by water source blocks, it creates a permanent, breathable air pocket. This is the fundamental trick that makes stationary underwater bases and simple submarines possible.
For an Advanced Redstone Submarine
If you want to build a submarine that uses pistons to physically move and submerge, you will need a more technical inventory.
– Sticky Pistons (many).
– Redstone blocks.
– Observers.
– Slime blocks or honey blocks (for movement).
– Levers, buttons, or pressure plates for controls.
– A reliable building block that is not moved by pistons (like Obsidian or Glazed Terracotta) for the frame.
Method One: The Simple Door Submarine
This is the quickest way to get a mobile, breathable pod underwater. It is perfect for survival mode and requires no complex redstone.
Building the Hull and Air Pocket
Start by building the shape of your submarine on dry land. Create a small, enclosed space just big enough to stand in—a 3x3x3 cube is a good starting point. Leave one wall open for now. Place a door in a 1×2 gap on the floor or wall inside this space. The door must be inside the fully enclosed block space.
Once your structure is sealed except for one entry, carefully bring your water bucket and pour water source blocks over the entire structure. The water should flow and cover it completely, but the interior where the door is located will remain dry. You can now break the temporary block sealing your entry and swim inside through the water curtain. When you close the door inside, it will push the water out of its block space, creating your air pocket.
Making It Mobile
Here is the clever part. Your submarine is now a stationary air pocket. To move it, you must break and replace blocks. From inside your sub, use your pickaxe to break the block in the direction you want to travel. Immediately place a new block in that same spot from inside. Then, break the block behind you. This process slowly “walks” your air-pocket enclosure forward through the water.
It is slow and methodical, but it works. For forward visibility, ensure the block you break in front of you is glass, which you can see through before replacing it. This method is excellent for short-range exploration to a specific shipwreck, but not for cross-ocean voyages.
Method Two: A Redstone-Powered Automated Submarine
For a truly impressive vessel that moves with the flip of a switch, you will need to engineer with pistons. This build is more suited to creative mode or a survival world with an established redstone farm.
Designing the Piston Drive Mechanism
The core idea is a “flying machine” adapted for underwater use. A basic horizontal flying machine uses two sticky pistons facing each other, with a block like a redstone block or slime block between them. By powering the pistons in sequence, it pushes itself forward.
Start by building this simple engine on dry land to test it. Place a block. On one side, place a sticky piston facing away from the block. On the other side of the block, place another sticky piston facing the first one. Place a redstone block on the face of the first piston. When you power the second piston, it will pull the block and the attached redstone block, which then powers the first piston to extend, moving the whole assembly one block forward. Using observers can automate this cycle into continuous movement.
Constructing the Submarine Body and Controls
Once your engine works, you need to build a waterproof hull around it and yourself. Construct a wider frame of immovable blocks (like obsidian) around the flying machine mechanism. Then, build your crew compartment within this frame, using glass for a windshield. The key is to ensure the moving pistons and redstone blocks are inside the hull so water does not wash them away.
For controls, place levers on the inside wall connected to the piston circuit. One lever could be the master power for the forward engine. You can build a second, identical engine oriented vertically to act as a “dive plane,” allowing you to submerge and surface on command by activating the vertical drive.
Waterproofing and Final Assembly
Before you flood the area, double-check that every part of your redstone circuit is enclosed by solid blocks. Any exposed redstone dust, a repeater, or a comparator will be washed away by water. Seal the entire hull. To launch your sub, you will need to submerge it. The easiest way is to build it in a dry dock (a sealed chamber), then break a wall to let the ocean water in. Your interior, if fully sealed with a door air lock, will remain dry.
Troubleshooting Your Minecraft Submarine
Even the best-laid plans can spring a leak. Here are common issues and how to fix them.
Water Flooding the Interior
If your interior floods, you have a missing block or an unsealed gap. In creative mode, use the fill command to replace water with air temporarily. In survival, you will need to place blocks to slowly push the water out, starting from the lowest point. Always carry a sponge for emergency water removal. For door-based subs, ensure the door is placed correctly in a 1×2 space and that the blocks directly adjacent to it are solid.
Redstone Mechanisms Failing Underwater
Water breaks redstone wire. If your automated sub stops moving, check for any redstone component that is not behind a protective block. All circuits must be “dry.” Also, ensure your pistons are not trying to push blocks that are waterlogged, as this can cause weird behavior. Using waterloggable blocks like stairs or slabs in your hull can sometimes interfere.
Getting Stuck or Movement Issues
Piston submarines can get stuck on seabed terrain or coral. Design your hull to be slightly elevated from the ocean floor using fences or walls as a “skid.” For door submarines moving through kelp forests, it is often easier to go above or around them, as breaking and replacing blocks in kelp is slow.
Taking Your Submarine on Its Maiden Voyage
Your vessel is ready. What now? The oceans of Minecraft are filled with destinations perfect for submarine exploration.
– Ocean Monuments: Use your sub to approach these dangerous structures. You can observe the guardians from the safety of your glass cockpit before planning your raid.
– Shipwrecks and Underwater Ruins: Cruise along the ocean floor, using your sub’s interior as a safe base to loot chests and gather materials.
– Deep Ocean Trenches: Some of the most stunning underwater vistas are in the deep, dark ocean biomes. A submarine with a good glass dome is the best way to enjoy them without constant drowning anxiety.
Remember to light up the interior of your sub with sea lanterns, glowstone, or lanterns. This prevents hostile drowned from spawning inside your vessel if it is ever left unoccupied in a dark ocean biome.
From Functional to Fantastic
Once the mechanics work, you can focus on aesthetics. Add details with stairs and slabs to create a rounded hull. Use iron trapdoors as exterior hatches or vents. Place levers and buttons on a control panel inside. For the ultimate touch, build a docking bay in an underwater base, using pistons to open and close a hangar door made of glass or iron blocks.
The journey from a simple door in a box to a sleek, cruising submarine encapsulates what makes Minecraft engineering so rewarding. You start with a problem—how to breathe and move underwater—and through a combination of game mechanics and creativity, you build a solution that opens up a whole new layer of the game world. So gather your blocks, craft your doors, and prepare to dive deep. The ocean depths are waiting, and now you have the perfect vessel to explore them.
