Introduction
Designing a high-performance model aircraft wing requires careful attention to both geometry and aerodynamics. While many established tools focus primarily on aerodynamic simulation, comparatively few address the quality, structure, and usability of the geometric design process itself.
With PlanformCreator2 and AirfoilEditor, Jochen Guenzel has developed a pair of complementary open-source tools that together form a coherent, parametric, and highly interactive design workflow. Beyond their technical capabilities, these tools distinguish themselves through an exceptionally clear and well-designed graphical user interface, enabling both experienced designers and near-newcomers to explore wing and airfoil design with confidence.
Origins and Design Philosophy
Both applications originated from practical design needs rather than academic abstraction. PlanformCreator2 was developed as a successor to the original PlanformCreator from the Strak Machine project, when further development of the original tool became restrictive.
AirfoilEditor began as a supporting module within PlanformCreator2, intended to simplify everyday airfoil-related tasks. As its functionality grew, it evolved into a stand-alone airfoil design and inspection tool.
A central philosophy shared by both tools is that:
Good aerodynamics begin with clean, well-controlled geometry — and designers benefit enormously from immediate visual and aerodynamic feedback.
As a result, Jochen deliberately focused on geometry quality, parametric control, and user experience, while interfacing with proven external solvers such as XFoil, XFLR5, and FLZ_vortex.
A Graphical User Interface That Encourages Understanding
Clarity, Readability, and Visual Precision
One of the most striking aspects of both PlanformCreator2 and AirfoilEditor is the exceptional readability of their graphical interfaces. Diagrams are:
- Clean and uncluttered
- Precisely scaled and clearly annotated
- Visually consistent across views
Key elements such as chord distribution, reference and hinge lines, airfoil curvature, and polar curves are displayed in a way that makes relationships immediately apparent — even to users encountering these concepts for the first time.
A User Experience Designed for Exploration
Unlike many technical tools that rely heavily on CLI (command line interface) dialogs or/and numerical tables, these applications emphasize direct graphical interaction:
- Parameters can be adjusted incrementally
- Changes are reflected immediately in the geometry
- The software responds smoothly rather than abruptly
This creates a forgiving environment in which users can safely test ideas, undo changes, and gradually build understanding.
For a near-newcomer, this is a crucial advantage: instead of being overwhelmed, the interface actively encourages curiosity and experimentation.
Precision Without Intimidation
Despite their accessible appearance, both tools maintain a high level of numerical and geometric precision. Exact values can be entered where required, while graphical manipulation allows intuitive control where insight matters more than numbers.
This balance — power without intimidation — is rarely achieved in technical design software and represents a genuine strength of the toolset.
AirfoilEditor: Geometry, Smoothness, and Immediate Feedback
Bezier-Based Airfoil Reshaping
One of the most valuable features of AirfoilEditor is the ability to reshape airfoils using Bezier curves rather than raw coordinate manipulation.
Upper and lower surfaces are represented by smooth Bezier curves controlled by a limited number of intuitive control points. This approach offers decisive advantages:
- Intrinsically smooth airfoil geometry
- Elimination of numerical noise and artifacts
- Controlled, predictable shape changes
A particularly important consequence is that aerodynamic polars generated from Bezier-based airfoils are significantly smoother and more stable, as abrupt curvature changes — a common cause of noisy XFoil results — are avoided.
Existing airfoils can also be automatically approximated using Bezier curves, allowing designers to clean up legacy profiles while preserving their essential characteristics.
Near Real-Time Polar Generation with XFoil
AirfoilEditor integrates tightly with XFoil, enabling near real-time polar generation as geometry changes are made.
This transforms airfoil design into an interactive process:
- Modify thickness, camber, or curvature
- Immediately regenerate the polar
- Instantly assess the aerodynamic impact
Rather than working in slow, batch-oriented cycles, designers receive rapid feedback, making it far easier to understand cause-and-effect relationships between geometry and performance.
Direct Design Mode
Building on this capability, AirfoilEditor offers a direct design mode in which each geometry modification creates a new design state along with its corresponding polar.
Designers can step through successive iterations, effectively browsing a history of geometry–polar pairs. This approach is particularly valuable for:
- Learning and intuition building
- Sensitivity studies
- Fine-tuning airfoils for specific Reynolds-number ranges
PlanformCreator2: Visual and Parametric Wing Design
PlanformCreator2 applies the same user-centric philosophy to wing planform design.The wing is defined parametrically, using normalized span and chord distributions, reference lines, hinge lines, and advanced shaping functions. Complex concepts such as flap depth, spanwise variation, and reference-line curvature are presented graphically and intuitively, rather than hidden behind abstract parameters.
As a result, even users with limited prior experience can understand what defines a wing planform and confidently explore variations.
Spanwise Reynolds-Aware Polar Evaluation
When PlanformCreator2 and AirfoilEditor are used together, a particularly powerful capability emerges:
Polars Along the Wing
PlanformCreator2 defines the spanwise position and chord length of each wing section. Using this information, AirfoilEditor can calculate polars that account for:
- The airfoil’s actual position along the wing
- The local chord length
- The corresponding local Reynolds number
This allows designers to evaluate airfoil performance under realistic operating conditions along the entire span, rather than relying on a single, arbitrary Reynolds number.
For tapered or twisted wings, this represents a substantial improvement in realism and design confidence.
An Integrated, Learnable Workflow
Together, the two tools form a coherent workflow:
AirfoilEditor
- Clean and reshape airfoils using Bezier curves
- Ensure smooth curvature and stable polars
- Generate near real-time XFoil polars
- Evaluate performance at realistic Reynolds numbers
PlanformCreator2
- Define wing planform geometry parametrically
- Assign airfoils and strak transitions
- Export optimized geometry for analysis and CAD
External Tools
- Detailed analysis in XFLR5 or FLZ_vortex
- CAD development via DXF or CSV export
This workflow is powerful, yet approachable — allowing a near-newcomer to start experimenting quickly, while still offering depth for advanced users.
Conclusion
PlanformCreator2 and AirfoilEditor together represent a rare combination of technical depth and outstanding usability. Their clean, readable, and precise graphical interfaces make advanced aerodynamic concepts accessible, while features such as Bezier-based airfoil reshaping, near real-time polar generation, and spanwise Reynolds-aware evaluation provide tangible, everyday benefits.
Perhaps their greatest achievement is that they allow users to learn by doing — testing ideas, making modifications, and immediately seeing the consequences — without the frustration or intimidation common in many established tools.
For anyone interested in wing and airfoil design, from curious beginners to experienced designers, this toolset offers a modern, insightful, and genuinely enjoyable approach.
🔗 PlanformCreator2 (wing planform design)
➡️ https://github.com/jxjo/PlanformCreator2
🔗 AirfoilEditor (airfoil viewing & editing)
➡️ https://github.com/jxjo/AirfoilEditor