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Fusion Space

Loft

flight simulator
TipDocs

Import an OpenRocket .ork, RockSim .rkt or RASAero .CDX1 design and Loft simulates the flight in your browser — apogee, speed, stability, and recovery — and compares against the numbers the design tool stored in the file. It runs on a phone, offline once loaded. Results are estimates from a model; see how they're computed and where the model is weak.

Import an OpenRocket, RockSim or RASAero design

.ork, .rkt or .CDX1. Runs in your browser — never uploaded.

Or try a bundled example

Why Loft

Nothing to install, nothing to pay, nothing to sign up for
It runs on your device, in a tab. No account, no upload, no tracking. Install it to your home screen and it keeps working with no signal — at the pad, in a field, on a phone.
It reads the file you already have
OpenRocket .ork, RockSim .rkt and RASAero .CDX1 — each into the same model, so a design you imported and one you built here are edited and flown by exactly the same tools.
It shows you more than one answer
Loft's own solver, the numbers the file already stores from the tool that made it, and an independent RocketPy run in your browser — side by side. Where they disagree it says so instead of picking one and looking confident.

Once a design is loaded

  • Build and edit, not just view

    Start from a stable design or reshape an imported one — drag the fins, the body wall, the nose on the diagram, or type the numbers. It re-flies as you go.

  • Compare every fitting motor

    Fly the airframe on every bundled motor of the casing it already flies, at once: apogee, max speed, rail-exit velocity, thrust-to-weight, stability, flutter margin, and the delay to drill.

  • Sweep one dimension

    The response curve behind a single edit — how apogee, speed, stability or flutter margin move as you change it.

  • Fly it hundreds of times

    Monte-Carlo dispersion over your own stated tolerances: the apogee band to expect, the landing scatter, and the recovery area to plan for.

  • Check it against a second engine

    RocketPy — an independent 6-DOF simulator — flies the same design in your browser, so Loft's answer isn't the only one you get.

  • …and against your own file

    An .ork or .rkt carries its tool's own stored simulation. Loft shows its result beside those numbers rather than asking you to trust one.

All of it runs on your device — no account, nothing uploaded, and it keeps working at the pad with no signal once loaded.

Use it offline & install it

Loft runs entirely in your browser. Once you've opened it on a device with a connection, it keeps working with no signal — so you can import a design and simulate it at the pad. Install it and it opens like any app, full-screen and offline.

  • iPhone / iPad (Safari): Share → Add to Home Screen.
  • Android (Chrome): use the Install button above, or menu (⋮) → Add to Home screen.
  • Desktop (Chrome / Edge): the install icon in the address bar, or menu → Install Loft.

The motor database and the simulation run on the device, so a design imported offline still simulates. Open it online now and again to pick up any updates.