Heliciel MCP — propellers, wings and turbines, actually computed

Remote MCP server that turns an AI assistant into a propeller and turbine design engineer.

Every number comes from a real BEM (Blade Element Momentum) computation run by the

Heliciel engineering software — not from the model's guess.

https://mcp.heliciel.com/mcp

A real session — a 1140 mm, 3-blade marine propeller at 105 rpm: 1002.7 N of thrust,

222.4 N·m of torque, 2.45 kW, 92 % efficiency. Every figure computed by Heliciel, none of it

written by the model. The viewer renders inline in ChatGPT; in Claude the same viewer opens

from a link.

Why this exists

Ask any assistant to "design a propeller" and it will produce something plausible: a diameter,

a blade count, an efficiency figure. None of it is computed. For a conversation piece that is

fine; for something you are going to machine, print or bolt onto a boat, it is worse than

useless — a wrong number that looks right.

This server hands the assistant a real solver. It refuses to invent: missing parameters are

asked for, values inherited from a loaded model are flagged as inherited, and a failed

computation is reported as-is rather than replaced by an estimate.

What you can design

Aircraft propellers · drone and multirotor propellers · marine propellers · axial fans ·

wind turbines · hydro turbines, including ducted Kaplan runners · wings and hydrofoils.

What the assistant can do

**Full tool catalogue → docs/TOOLS.md** — 76 tools, generated from the live server.

Try it

> *"I have an 8 kg drone with 4 motors and a 150% thrust margin. Size the propellers."*

>

> *"Design an aircraft propeller: 50 kW, 120 km/h, max diameter 1.5 m, 2 blades."*

>

> *"Load a wind turbine, 3 blades, 4 m diameter, 8 m/s wind — what power can I harvest?"*

>

> *"Design a Kaplan runner for 5 m³/s and a 4 m net head, then show me the efficiency curve."*

>

> *"Compare 2 vs 3 blades and show me the best one in 3D."*

Connect

In Claude — install from the connectors directory,

nothing to configure.

Everywhere else — the server URL above, over streamable HTTP, with OAuth 2.0 + PKCE.

Per-client configuration blocks: **docs/CLIENTS.md**.

You need a Heliciel MCP pass — day, week or month — from

mecaflux.com. Nothing is sold inside the

conversation. You connect once and paste your pass key on the consent screen.

How it works

Each pass gets its own private Heliciel instance: the real Windows application, driven

through its own interface rather than through a reimplementation of it. No state is shared

between users. Your design projects are not archived — the session folder is erased when the

instance is recycled, and download links expire after 60 minutes.

That architecture is why the numbers are the software's own. It is also why the first call of

a session can take up to two and a half minutes if an instance has to start, and why long

optimizations return progress milestones rather than blocking: past 120 s a tool answers

`commande_en_cours`, and `lire_etat_commande` reports the generations as they complete.

Honesty, by construction

• Every number given to the user comes from a tool result. The server instructs the model never

to invent or estimate one.

• Images come from the software's own screen. The model is instructed never to generate a

picture of Heliciel or of its results — a generated image of engineering results is a

fabrication, whatever it looks like.

• Values inherited from the loaded model, rather than stated by the user, are returned flagged

as inherited.

• A quantity that has not been computed is not published. It is returned as unavailable,

with the reason and the tool to call — never as a zero that would read as a result.

• Heliciel's own design alerts travel with the results, so a computation that succeeds while

flagging a geometry to rework says so.

Limits, stated

• Performance is ideal and theoretical: surfaces are treated as aerodynamically smooth,

profile lift and drag data are generated by XFOIL, and fluid compressibility is not taken

into account — precision therefore drops at transonic and supersonic speeds.

• No acoustic model: blade-passing frequencies and tip speed are computed, an SPL dB(A)

level at a distance is not — and is not estimated in its place.

• Off-design and reverse-engineering modes are less precise than a computation at optimal twist.
• This is design assistance. Test your build, and do not put anyone at risk on the strength of

a computation alone.

Repository contents

The Heliciel software itself is proprietary and is not published here. This repository holds

the public description of the MCP service.

Links

• Documentation — https://www.mecaflux.com/suite/en/heliciel-mcp.htm
• Privacy policy — https://www.mecaflux.com/suite/en/confidentialite.htm
• Heliciel — https://www.heliciel.com/en/
• Support — https://www.mecaflux.com/suite/contact.php

Published by Mecaflux / Heliciel — fluid-mechanics software since 2005.