Aircraft Analysis Pipeline

A shared-CPACS aircraft analysis pipeline built on four independent Model Context Protocol (MCP) servers. A single CPACS XML file serves as the central data backbone; each MCP reads its inputs from and writes its results back into that file, enabling flexible, version-tracked multidisciplinary analysis.

Architecture

                ┌──────────────┐
                │  CPACS XML   │  ← single source of truth
                │  (versioned) │
                └──────┬───────┘
       ┌───────────────┼───────────────┐───────────────┐
       ▼               ▼               ▼               ▼
  ┌─────────┐    ┌─────────┐    ┌──────────┐    ┌──────────┐
  │ TiGL    │    │ SU2     │    │ pyCycle  │    │ Mission  │
  │ MCP     │    │ MCP     │    │ MCP      │    │ MCP      │
  │ v0.3.0  │    │ v0.3.0  │    │ v0.3.0   │    │ v0.2.0   │
  └────┬────┘    └────┬────┘    └────┬─────┘    └────┬─────┘
       │              │              │               │
  Geometry       Aerodynamics    Engine Cycle    Mission/Traj
  (wings,        (CL, CD,       (TSFC, Fn,     (fuel burn,
   fuselages,     L/D)           OPR, BPR)      GTOW, range)
   STEP export)

CPACS Versioning

Each time an MCP adapter completes, it commits a new numbered version of the CPACS XML. This gives a full audit trail:

Version	Author	Contents
v0	file_load	Original CPACS as loaded from disk
v1	tigl-mcp	+ geometry analysis results (wing/fuselage counts, bounding boxes)
v2	su2-mcp	+ aerodynamic coefficients (CL, CD, L/D)
v3	pycycle-mcp	+ engine performance (TSFC, thrust, OPR, BPR)
v4	mission-mcp	+ mission results (fuel burn, GTOW, trajectory)

All version snapshots are saved as cpacs_v0.xml, cpacs_v1.xml, etc., so you can compare or restore any previous state.

XPath Ownership

Each MCP reads from and writes to designated sections of the CPACS tree:

MCP	Reads	Writes
TiGL	.//vehicles/aircraft/model, .//vehicles/profiles	.//analysisResults/tigl
SU2	.//vehicles/aircraft/model/reference, .//analysisResults/tigl	.//analysisResults/aero
pyCycle	.//vehicles/engines	.//vehicles/engines/engine/analysis/mcpResults
Mission	.//reference, .//analysisResults/aero, .//mcpResults	.//analysisResults/mission

No two MCPs write to the same XPath, preventing conflicts.

Quick Start

Prerequisites

Dependency	Install
Python >= 3.12	—
SU2_CFD	~/.local/su2/bin/SU2_CFD
Gmsh	brew install gmsh or pip install gmsh
OpenMDAO + pyCycle	pip install openmdao==3.36.0 om-pycycle
Aviary (optional)	pip install aviary==0.9.10 dymos==1.13.1

Critical: Aviary requires openmdao==3.36.0 and dymos==1.13.1. Newer versions cause unit-compatibility errors.

Install MCPs

pip install -e tigl-mcp/
pip install -e su2-mcp/
pip install -e pycycle-mcp/
pip install -e mission-mcp/
pip install -e "mission-mcp/[aviary]"  # optional

Run the Pipeline

# All four MCPs on D150
./run_pipeline.sh d150

# Specific MCPs only
./run_pipeline.sh d150 --mcps tigl su2

# Custom flight conditions
./run_pipeline.sh d150 --mach 0.85 --aoa 3.0

# Other examples
./run_pipeline.sh canards
./run_pipeline.sh dlrf25

Run Tests & OVS

./run_pipeline.sh --test       # Pipeline integration tests
./run_pipeline.sh --ovs        # OVS validation suite
./run_pipeline.sh --test-all   # Everything

MCP Repositories

MCP	GitHub	Version	Description
TiGL	cmudrc/tigl-mcp	0.3.0	CPACS geometry parsing, STEP export
SU2	cmudrc/su2-mcp	0.3.0	CFD aerodynamic analysis (Euler)
pyCycle	cmudrc/pycycle-mcp	0.3.0	Turbofan engine cycle analysis
Mission	cmudrc/mission-mcp	0.2.0	Mission analysis (Aviary + NSEG)

Directory Structure

aircraft-analysis/
├── README.md              ← This file
├── run_pipeline.sh        ← Convenience runner
├── shared_cpacs/          ← CPACSManager + XPathRegistry
│   ├── __init__.py
│   ├── manager.py
│   └── xpath_registry.py
├── ovs/                   ← Output Verification System
│   └── validator.py
├── pipeline/              ← Orchestrator
│   └── shared_cpacs_orchestrator.py
├── examples/              ← Sample CPACS files
│   ├── D150_v30.xml
│   ├── canards.xml
│   └── DLR-F25_simple.xml
└── docs/
    ├── architecture.md
    └── parameters.md

Output Verification System (OVS)

The OVS validates that each MCP's output meets structural and plausibility requirements:

• Structural checks: Required XPaths exist and are properly nested
• Range checks: Numerical values fall within physically plausible bounds (e.g., CL ∈ [-2, 3], TSFC ∈ [0, 5])
• Cross-MCP checks: Later MCPs can verify their inputs from earlier MCPs

OVS runs as a CI check (.github/workflows/ovs.yml) on every MCP repository.

Example Results (D150)

Domain	Key Results
TiGL	5 wings, 2 fuselages, STEP exported
SU2	CL=0.074, CD=0.021, L/D=3.48, Euler solver
pyCycle	TSFC=0.885, Fn=26528 N, OPR=30.6, BPR=1.5
Mission (Aviary)	Fuel=5812 kg, GTOW=62732 kg, Converged

License

MIT