Wing Weight Calculator
Precision Engineering Tool to Calculate Weight of Wing Structures
Wing Weight Estimator
Total length of the wing from tip to tip.
Please enter a valid positive number.
Average width of the wing (Standard Mean Chord).
Please enter a valid positive number.
Maximum thickness of the airfoil as a percentage of chord (e.g., 12 for 12%).
Enter a value between 1 and 50.
Expanded Polystyrene Foam (EPS) – 15 kg/m³
Extruded Polystyrene Foam (XPS) – 30 kg/m³
Balsa Wood Structure (Light) – 160 kg/m³
Composite / Carbon Fiber Shell – 300 kg/m³ (Effective)
Solid Aluminum (Reference) – 2700 kg/m³
Select the primary material. Effective density assumes solidity factor.
Percentage of wing volume that is solid material (e.g., 100% for solid foam, 15-20% for hollow/ribbed).
Enter a percentage between 1 and 100.
Estimated Wing Weight
0.00 kg
Formula Used: Weight = (Span × Chord × Thickness% × 0.7) × Solidity% × Density
Note: 0.7 is an approximate coefficient for standard airfoil cross-sectional area.
Note: 0.7 is an approximate coefficient for standard airfoil cross-sectional area.
Wing Planform Area
0.00 m²
Total Enclosed Volume
0.00 m³
Material Volume
0.00 m³
Aspect Ratio
0.00
Weight Component Breakdown
| Parameter | Value | Unit |
|---|
Material Comparison (Same Geometry)
Estimated weight if constructed with different materials (keeping solidity constant)
A Comprehensive Guide to Calculate Weight of Wing Structures
In aerospace engineering and model aviation, the ability to accurately calculate weight of wing structures is fundamental to flight performance. Whether you are designing a UAV, an RC plane, or analyzing a light aircraft, the wing often constitutes a significant percentage of the total structural mass. This guide will walk you through the mathematics, practical applications, and engineering factors required to estimate wing weight effectively.
What is Wing Weight Calculation?
Wing weight calculation is the process of estimating the mass of an aircraft's lifting surface before it is physically built. This estimation involves determining the volume of the wing based on its geometric properties—span, chord, and airfoil thickness—and applying the density of the chosen construction materials.
Who needs this?
- Aerospace Engineers: To ensure the aircraft meets center of gravity (CG) requirements.
- RC Hobbyists: To estimate wing loading and choose appropriate motors and batteries.
- Drone Designers: To optimize flight time by minimizing structural weight.
A common misconception is that wing weight is solely determined by surface area. In reality, the internal volume and internal structure (ribs, spars, skin) play a far more critical role in the final result when you calculate weight of wing components.
Wing Weight Formula and Mathematical Explanation
To calculate weight of wing structures accurately, we treat the wing as a geometric volume with a specific density. The simplified engineering formula used in our calculator is derived as follows:
Step 1: Calculate Planform Area ($S$)
$S = \text{Span} \times \text{Mean Chord}$
Step 2: Estimate Enclosed Volume ($V_{total}$)
Airfoils are not rectangles; they are curved. The cross-sectional area of an airfoil is typically about 65% to 75% of the bounding rectangle defined by the chord and maximum thickness. We use a coefficient ($k \approx 0.7$).
$V_{total} = S \times (\text{Thickness Ratio}) \times k$
Step 3: Apply Solidity and Density ($W$)
Since most wings are not solid blocks (except foam wings), we apply a solidity factor ($f_{solid}$) to account for the air inside the wing.
$W = V_{total} \times f_{solid} \times \rho_{material}$
Variable Table
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| $b$ | Wing Span | Meters (m) | 0.5m – 50m |
| $c$ | Mean Chord | Meters (m) | 0.1m – 5m |
| $t/c$ | Thickness Ratio | Percentage (%) | 8% – 18% |
| $\rho$ | Material Density | kg/m³ | 15 (Foam) – 2700 (Alum) |
Practical Examples (Real-World Use Cases)
Example 1: RC Glider Wing (Foam Core)
An RC enthusiast wants to calculate weight of wing for a thermal glider cut from solid XPS foam.
- Inputs: Span = 2.0m, Chord = 0.2m, Thickness = 10%, Material = XPS Foam (30 kg/m³), Solidity = 100% (Solid).
- Area: $2.0 \times 0.2 = 0.4 \text{ m}^2$
- Volume: $0.4 \times 0.02 \text{ (thickness height)} \times 0.7 = 0.0056 \text{ m}^3$
- Weight: $0.0056 \times 30 = 0.168 \text{ kg (168g)}$
Example 2: UAV Wing (Composite Shell)
A drone designer needs to estimate the weight of a hollow carbon fiber wing.
- Inputs: Span = 1.5m, Chord = 0.25m, Thickness = 15%, Material = Composite (300 kg/m³ effective), Solidity = 15% (Hollow shell).
- Area: $1.5 \times 0.25 = 0.375 \text{ m}^2$
- Total Volume: $0.375 \times 0.0375 \times 0.7 = 0.0098 \text{ m}^3$
- Material Volume: $0.0098 \times 0.15 = 0.00147 \text{ m}^3$
- Weight: $0.00147 \times 300 \approx 0.44 \text{ kg (440g)}$
How to Use This Wing Weight Calculator
- Enter Geometry: Input the total span and average chord length of your wing design in meters.
- Define Airfoil: Enter the thickness percentage. Fast aircraft use thin wings (8-10%), while cargo planes use thick wings (14-18%).
- Select Material: Choose the primary construction material. The calculator adjusts the density automatically.
- Adjust Solidity: If you are building a hollow wing with ribs, set solidity to 15-25%. If using solid foam, set it to 100%.
- Analyze Results: Use the "Weight Component Breakdown" table to see how volume contributes to mass, and check the chart to compare materials.
Accurate input is crucial. If you are unsure of the Mean Chord, approximate it by averaging the root chord (center) and tip chord.
Key Factors That Affect Wing Weight Results
When you calculate weight of wing designs, several physical and financial factors influence the final metric:
- Aspect Ratio (AR): High aspect ratio wings (long and skinny) require stronger, heavier spars to resist bending moments, often increasing structural weight disproportionately.
- Material Selection: Carbon fiber offers high strength-to-weight ratios but increases cost. Wood is cheaper but may require more volume for the same strength.
- Structural Loads (G-Force): Wings designed for aerobatics (high G-loads) require internal reinforcement, increasing the effective solidity factor and weight.
- Manufacturing Method: A molded hollow wing is often lighter than a solid foam wing, but the molds are expensive (financial trade-off).
- Skin Thickness: The outer skin usually accounts for 60% of a wing's weight. A 1mm increase in skin thickness can drastically change the result.
- Joiners and Hardware: The calculator estimates structural weight, but servos, wing joiners, and glue can add 10-20% to the final "flying weight".
Frequently Asked Questions (FAQ)
- Q: Does this calculator include the weight of servos and motors?
A: No, this tool focuses strictly on the structural weight of the wing (foam, wood, composite). You must add electronics weight separately. - Q: How do I calculate Mean Chord for a tapered wing?
A: For a trapezoidal wing, Mean Chord $\approx (Root Chord + Tip Chord) / 2$. - Q: Why is the Solidity Factor important?
A: A wing is rarely a solid block of metal. It is mostly air. Solidity represents the percentage of the volume actually occupied by material. - Q: Can I use this for delta wings?
A: Yes, but ensure you calculate the surface area correctly by using the correct Mean Aerodynamic Chord (MAC). - Q: What is a good target weight for an RC plane wing?
A: A typical target is a wing loading of 30-50 g/dm². Use the "Wing Planform Area" result to check your loading. - Q: How does thickness ratio affect weight?
A: Thicker wings enclose more volume. If the wing is solid, weight increases linearly with thickness. If hollow, the effect is smaller but drag increases. - Q: Is the 0.7 airfoil coefficient standard?
A: It is a widely accepted engineering approximation for subsonic airfoils. Supersonic airfoils may have a coefficient closer to 0.5. - Q: Does paint or covering add weight?
A: Yes! Covering film (Monokote) adds about 60-80 g/m². Include this margin when interpreting your results.
Related Tools and Internal Resources
Explore more engineering calculators to refine your aircraft design:
- Wing Loading Calculator – Determine if your wing area is sufficient for the aircraft's mass.
- Center of Gravity (CG) Optimizer – Balance your aircraft for stable flight.
- Thrust to Weight Ratio Calculator – Match your engine power to your airframe weight.
- Composite Material Density Chart – Detailed density data for carbon fiber and fiberglass.
- Airfoil Selection Guide – Choose the right thickness ratio for your mission profile.
- Aspect Ratio Calculator – Analyze the efficiency of your wing planform.