How to Host a Create Aeronautica Server: NeoForge 1.21.1 Setup Guide

Start with 6 GB of RAM. That's Create Aeronautica's own recommended floor, not a third-party guess — the pack runs NeoForge 1.21.1 plus Create's rotation and motion simulation for every flying contraption players build, and that combination needs headroom from the first boot, not after you notice lag.

Import the modpack cleanly through a modpack installer instead of guessing which files to copy from a client export. Create Aeronautica depends on exact NeoForge and Create versions lining up, and a half-copied client folder is the most common way to end up with a server that boots into a wall of missing-dependency errors.

Watch the console through the full first boot. Create's rotation and motion systems initialize a lot of machinery state on startup, and on a pack built entirely around custom flying contraptions you want to see that finish cleanly — no repeating stack traces, no mod stuck mid-load — before you consider the server ready.

Only invite players once that first clean startup has actually completed. Letting people join while the world and Create's kinetic network are still settling is how you get the first crash report on day one, before anyone's even built anything.

Take a backup before any world import, loader update, or config change. Create Aeronautica players sink real time into engineering working flying machines from scratch — losing that to an untested change is a much bigger deal here than on a pack where everything is default-crafted.