
Lightspeed Boat
The cool way to travel fast, now in Java Edition!
Screenshots


About this Mod
Lightspeed Boat
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The cool way to travel fast, now in Minecraft™ Java Edition!
Summary
Lightspeed boat is originally a bug feature in Bedrock Edition, where boats receives no friction when on slabs. This allows for accelerating boats to enourmously high speeds using flowing water. (Note: It is now half-fixed in Bedrock Edition)
This mod brings the feature to Java Edition. Enjoy cool automatable fast travel systems!

The figure above is an available design for accelerating boats. Read more about Lightspeed Boat on Minecraft Wiki.
WARNING: This mod must be present on both server and client, otherwise some server-client desync can occur.
Note: By default, the mod has a protective measure that prevent the speed from exceeding 72.73m/s (the blue ice speed).
Details
Here are the mechanical details of the mod.
The boat will enter lightspeed state, if it has a velocity greater than lightspeedThershold 2.4 (in m/s), and one of the following is satisfied:
- The boat's Y coord substracted by the floor of itself is between
slabHeightMin0.4999 andslabHeightMax0.5241. The boat must be either IN_WATER or ON_LAND. The block the boat is on cannot be Water or Bubble Column. (This requires the boat to be on a slab) - The boat's bounding box's maxY is integer, and the Y velocity of the boat is near zero. (This requires the use of Soul Sand Bubble Columns and Trapdoors)
If requireLevitating is enabled, the first condition will be disabled.
When under lightspeed state:
- The drag (horizontal velocity decay) will be constantly
lightspeedDrag0, unless the speed exceedsmaxLightspeed72.73. - If
allowPlayerDriveis false, the player will not be able to drive the boat, but can still turn it. - If
allowPlayerTurnis false, the player will not be able to turn the boat.
Values can be customized by editing the config/lightspeedboat-common.json file.
Available Versions
How to Install Lightspeed Boat on Your Server
Order Server
Order a Minecraft Java server with at least 3 GB RAM (4 GB recommended).
Set fabric Loader
In the panel under "Egg", select the fabric loader and matching Minecraft version (1.21).
Install Mod
Open the mod browser in the dashboard and search for "Lightspeed Boat". Click "Install" – done! Alternatively, upload the .jar via SFTP to the /mods folder.
Compatibility
Mod Loaders
Minecraft Versions
1.21, 1.20.6, 1.20.5 (+12 more)
Server-side
✓ RequiredRecommended RAM
4 GB(min. 3 GB)Frequently Asked Questions
Lightspeed Boat server crashes on startup – what to do?
Most common cause: wrong fabric version or insufficient RAM. Check the server log (latest.log) for "OutOfMemoryError" or "Mixin" errors. With Mado Hosting: ensure at least 3 GB RAM is allocated and the loader matches the mod version (1.21). You can switch loaders with one click in the panel.
Is Lightspeed Boat compatible with fabric and forge?
Lightspeed Boat officially supports fabric, forge for Minecraft 1.21, 1.20.6, 1.20.5. Note: Forge and Fabric mods are NOT cross-compatible – pick one loader and stick with it. The Mado dashboard automatically detects incompatible loader combinations.
Server lagging with Lightspeed Boat – how to optimize performance?
Recommended RAM: 4 GB (per 8 players). Use /spark profiler to check if Lightspeed Boat consumes the most tick time. Common fixes: reduce server view-distance to 8-10, install "performant" or "starlight" as supplementary mods on Forge. With Mado Hosting, your server runs on NVMe SSDs with dedicated CPU cores for minimal latency.
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