Parametric studies
It can write the script that varies chords, sweep or Reynolds number and generates the cases. For example, a family of wings through OpenVSP's Python API (programming interface), exported as .vsp3 and .stl.
Octo for open-source aeronautics software
From the wing sketch to simulation, on Linux.
OpenVSP, XFOIL, AVL, OpenMDAO, SU2, OpenFOAM, JSBSim, code_aster, Capella and pyNastran run on Ubuntu, and most of them run in batch. Octo can write the scripts that vary the parameters, launch the cases, gather the results and log each run, with everything prepared for human review. The engineer decides what holds for the project.
LinuxAllrun on Ubuntu
License: take careAGPL 3.0in RCAIDE
XFLR5AbandonedSourceForge label
Sources28listed at the end of the page
01
What Octo does with open-source software.
Six possible deliverables, drawn from the research. In all of them, an engineer decides and validates; Octo can take on the work of setting up, running and organizing.
Batches with no one at the menu
It can launch the cases from the command line (SU2_CFD, OpenFOAM dictionaries, JSBSim in batch mode), detect the ones that didn't converge and retry with a different setting.
Organized results
It can gather polars, coefficients and stresses into CSV or a spreadsheet, with charts comparing the variants.
Deliverable: consolidated CSV + chartsNastran model checked
With pyNastran, it can read the BDF (Nastran input file), count nodes and elements by type and flag elements without a property and unused materials, before the model goes to the solver. It doesn't need Nastran for that; only to solve.
Deliverable: BDF inventory + rewritten copyTools connected
It can stitch one tool's output into the next one's input (OpenVSP → Gmsh → SU2; RCAIDE → AVL), which today is usually done by hand. To optimize the whole, it proposes OpenMDAO, which is the plumbing and doesn't come with ready-made physics.
Deliverable: scripted chain + OpenMDAO modelA study you can redo
Records the assumptions, each tool's version and the exact command of each run, so the study can be redone later without guesswork.
Deliverable: record of assumptions, versions and commands
02
Eight arms, one open study.
The same Octo cycle, applied to open-source aeronautics tools. Each arm has a narrow role; the decisions are made by the responsible engineer.
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Discovery
Maps what's already in use
Which commercial tools the team uses, for which stage, and which open one does the same job. Separates conceptual studies from what goes into a certification process, which stays with qualified people and authorities.
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Data
Defines the exchange formats
.vsp3for geometry, BDF for structure, CSV for polars and coefficients, CPACS (an XML schema from DLR, the German Aerospace Center, for aircraft configuration) when the configuration needs to move between tools. One name per case, one folder per run. -
Security
Reads the exact license
AGPL 3.0 in RCAIDE, NOSA 1.3 in OpenVSP and GPL in Gmsh (closed use requires a commercial license). Before embedding anything in a product or service, the decision belongs to the company's legal team.
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Architecture
Builds the chain
Proposes low-order methods first (XFOIL, AVL, OpenAeroStruct) and CFD (computational fluid dynamics) to confirm (SU2 or OpenFOAM). Assesses with the team whether SU2's discrete adjoint is worth compiling, since the prebuilt binaries don't include it.
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Development
Writes the scripts
Uses each tool's documented API and flags what it didn't find in the documentation. In OpenVSP, the Python module needs the same Python version used to compile it; in XFOIL, it deletes the old polar first, because XFOIL appends to the file.
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Review
Checks against the reference
Before your own case, it runs the reference case documented by the project: OpenMDAO's paraboloid has to reach f ≈ −27.33 at x ≈ 6.67, y ≈ −7.33. Then it runs a few cases and checks the generated file, not the success message.
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Release
Runs the approved batch
With your OK, it runs the whole matrix, separates what converged from what didn't and returns the list, without hiding any case that failed.
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Documentation
Records what applies
Each tool's version, the command for each run, the model's assumptions and what was confirmed on your machine. The next study starts ready.
Octo prepares and runs for human review. The engineer says whether the result holds for the project; certification belongs to qualified people and authorities.
03
Each task, its own tool.
The table Octo uses to choose. Below, the equivalence with commercial tools: by function, not by qualification.
| Task | Open tool |
|---|---|
| Sketch the configuration and vary wing parameters | OpenVSP (Python API) |
| 2D airfoil polars | XFOIL (or XFLR5, with a GUI) |
| Stability derivatives and quick trim | AVL |
| Conceptual sizing and mission (including electric) | RCAIDE |
| Gradient-based system optimization | OpenMDAO (+ pyOptSparse) |
| Low-order wing aerostructural optimization | OpenAeroStruct |
| Reynolds-averaged CFD (RANS) and adjoint-based shape optimization | SU2 |
| General CFD (thermal, multiphase, varied cases) | OpenFOAM |
| Generate a mesh from CAD | Gmsh |
| Model a simple part or assembly with FEM (finite element method) | FreeCAD + CalculiX |
| Nonlinear structural FEM | code_aster or CalculiX |
| Read, check and change a Nastran model without Nastran | pyNastran |
| Simulate flight dynamics in batch / autopilot SITL (software-in-the-loop) | JSBSim |
| Visualize the flight | FlightGear |
| System architecture (MBSE, model-based systems engineering) | Capella |
| Exchange the configuration between tools in a common format | CPACS + TiGL |
| Commercial | Closest open tool | What's missing |
|---|---|---|
| CATIA / NX (conceptual) | OpenVSP | Detailing, PMI (manufacturing annotations on the 3D model), large assemblies, PLM (product lifecycle management) |
| CATIA / NX (mechanical part) | FreeCAD | Advanced surfacing, scale, PLM integration |
| ANSYS Fluent / STAR-CCM+ | SU2, OpenFOAM | Integrated interface, automatic mesher, support, vendor validation base |
| MSC/NX Nastran (solver) | CalculiX, code_aster | Nastran cards, elements and aeronautical workflows (aeroelasticity SOL 144/145/146) |
| Femap / Patran (Nastran pre/post) | pyNastran (scripted) | Full modeling interface |
| ModelCenter / Isight | OpenMDAO | Ready-made integration with commercial tools, graphical interface |
| MATLAB/Simulink (flight dynamics) | JSBSim (+ Python) | Flight-qualified code generation |
| Cameo / MagicDraw (SysML) | Capella | Uses Arcadia, not SysML |
| In-house sizing tools | RCAIDE, SUAVE | Methods calibrated with the company's data |
04
From the script to the chained study.
Three steps. Each one only makes sense after the previous one has shown results on your team.
A proposal, not a promise
On-demand scripts
On a Linux machine, the engineer asks for the study in engineering terms and gets the script and the results to review.
- “A family of wings with three sweep angles” becomes an OpenVSP script
- The reference case documented by the project, run before your own case
- Consolidated CSV and a list of what didn't converge
Case queue
Batches run in a queue, in parallel, over the approved study matrix.
- SU2 with
mpirun, OpenFOAM through dictionaries, JSBSim in batch mode - A case that doesn't converge comes back with another setting or goes to a person
- Run report with versions and commands
Optimized chain
The tools connected in a single study, with OpenMDAO driving the optimization.
- OpenVSP → AVL/XFOIL → OpenMDAO → SU2 or OpenFOAM
- CPACS + TiGL as the common configuration format
- Methods calibrated with the company's own data
05
Confirmed by sources.
Every point below has a source published by the vendor, the project or the responsible agency. The sources are in the next section.
6
points with a published source, each with its reference alongside.
- ConfirmedActive projects in October 2026
- OpenVSP 3.55.0 (Oct 12), JSBSim 1.3.3 (Oct 16), code_aster with tags 17.5.8 and 18.1.11 (Oct 16), OpenMDAO 3.45.2 (Oct 27), pyOptSparse 2.17.0 (Oct 28); SU2 with commits on Oct 28 and pyNastran with commits on Oct 26.Source: each project's download page, PyPI or GitHub/GitLab API, accessed on October 28, 2026
- ConfirmedRCAIDE is AGPL 3.0
- Using RCAIDE inside a network service requires opening the derived code. Worth reviewing with legal before embedding it in a product.Source: license detected by GitHub in leadsgroup/RCAIDE_LEADS
- ConfirmedOpenVSP is NOSA 1.3 and compiles from source
- NOSA is the NASA Open Source Agreement, NASA's own license, different from the licenses of the other tools on the list. On Ubuntu, the project page explains how to build the
.debwithmake packageand requires gcc 10, 13 or 14: 11 and 12 fail.Source: repository LICENSE and Ubuntu instructions at openvsp.org - ConfirmedXFLR5 labeled Abandoned; SUAVE with no push since Feb 2024
- SourceForge labels XFLR5 as “Abandoned”, despite version 6.62 from March 24, 2026. SUAVE is at 2.5.2, from 2022, with no push to the repository since February 2024.Source: sourceforge.net/projects/xflr5 and github.com/suavecode/SUAVE
- ConfirmedSU2 binaries without the discrete adjoint
- Shape optimization with the discrete adjoint requires compiling SU2. The prebuilt Linux binaries don't include this feature.Source: SU2 download page
- ConfirmedpyNastran doesn't solve; it only reads and writes
- Running the model still requires a Nastran. The PyPI version is 1.4.1, from March 2024, for Python 3.9 to 3.12; for newer Python, the project's documentation says to download from GitHub.Source: pyNastran repository and PyPI
06
What Octo does and what stays with you.
Octo prepares everything, but does not sign. The document of record stays with whoever is accountable for it.
Octo prepares
Surveys, calculates, organizes and generates the documents: spreadsheets, reports, drawings and drafts.
Deliverable: material ready to checkYour team checks
The licensed professional checks what Octo delivered before signing. If something doesn't add up, it goes back to Octo with the correction.
Step: review by the signerWho signs
Octo does not sign. Designs, technical reports, ART/RRT (Brazil's professional responsibility records), accountability reports and any official document are still signed by the company's or agency's licensed professional: here, the responsible engineer and the certification authority.
Sign-off: responsible engineer and certification authority
07
Sources.
Sites, repositories and packages published by each project, accessed on October 28, 2026.
- OpenVSPProject site
- OpenVSP on UbuntuBuilding and .deb
- OpenVSP APIGeom and File I/O groups
- OpenVSP licenseNOSA 1.3
- NASA Spinoff on OpenVSP2016
- SU2: downloadBinaries and discrete adjoint
- SU2: executionSU2_CFD, mpirun and scripts
- OpenFOAM Foundationv14 and Ubuntu package
- OpenFOAM ESIv2606
- GmshProject site and license
- FreeCAD: FEM solversCalculiX, Elmer, FEniCS, Mystran, Z88
- CalculiXProject site
- code_asterSource, license and tags
- OpenMDAO: paraboloidReference case
- OpenAeroStructMDO Lab
- pyOptSparseMDO Lab
- XFOIL guideCommands by menu
- AVLMIT
- XFLR5SourceForge, labeled Abandoned
- RCAIDE-LEADSRepository and license
- SUAVERepository
- JSBSimRepository and batch mode
- FlightGearDownload
- CapellaProject site and case studies
- pyNastranProject repository
- pyNastran: BDF overviewProject documentation
- CPACSDLR
- TiGLDLR
Your study, on Linux.
The assessment starts by listing the tools your team uses and the studies that repeat, without changing anything. Octo proposes a map of what can run on open-source software, with each tool's licenses and limits, and you decide with it in hand.