Try out Wing Load Here:
Quick Tip: When you open the calculator, remember to select which class of glider from the dropdown (it makes a difference).
On desktop you can compare up to 6 gliders within the same class at a time.
Why This Tool Exists
Most pilots rely solely on the Certified Weight Range on their wing (e.g., "75–95 kg") to determine if they are safe to fly. While certification guarantees that the wing will recover from collapses safely (so-called "Passive Safety"), it does not tell you how the wing will feel and fly ("Active Authority"), particularly in strong wind or thermic conditions.
Certification tests recovery.
Wing Loading contributes to performance: speed, internal pressure, handling, and wind penetration.
This calculator uses All up Weight divided by the Flat area (more on why below) to reveal the aerodynamic truth of your configuration, which often tells a different story than the marketing brochure.
Disclaimer This tool is meant as a guide to help contextualise how wing loading affects performance and handling. But it cannot be looked at in isolation. Pilot size, aspect ratio, and harness type all play a significant part. Always verify your wing’s certification status. Flying outside the manufacturer’s specified weight range voids certification and may alter flight characteristics beyond tested limits. This tool provides aerodynamic analysis, not legal or safety advice.
1. The Metric: What is Wing Loading?
Wing loading is simply your Total Take-Off Weight divided by the Flat Surface Area of the glider. (Projected area can be used, but Flat Area is the aerodynamic industry standard, so we use that to maintain consistency.)
Based on current feedback, many pilots would like to use the projected area and have classes based on aspect ratio.
My goal is to update this tool to give you this option in our southern hemishpere winter months (middle of the year 2026).
If you have any questions about the results or aren’t sure how to interpret your specific loading number, or have further suggestions for improvement, leave a comment below.
Low Loading (Light): The wing is "under-pressurized." It floats well in calm air but lacks the momentum to cut through wind or turbulence.
High Loading (Heavy): The wing is "highly pressurized." It is fast and solid but reacts more aggressively to collapses due to higher kinetic energy.
2. The "Small Wing" Disadvantage (The Scale Effect)
One of the most misunderstood and unfair realities of paragliding is that the math favors heavier pilots.
A large wing (28 m²) is inherently more efficient than a small wing (21 m²) due to the Scale Effect and Reynolds Numbers. To a small wing, the air feels "thicker" and "stickier," creating relatively more drag.
But beyond aerodynamics, the loading math itself is skewed:
Large Wings (e.g., Size L/XL): Pilots on these wings naturally achieve higher wing loading numbers. A pilot flying a Large wing, even in the middle of their weight range, often sits comfortably in the "Green Zone." They get solid pressure and good penetration by default.
Small Wings (e.g., Size XXS/XS): Pilots on these wings struggle to generate enough pressure. A small pilot can load their wing to the absolute maximum of the certified weight range and still fail to reach the optimal "Green Zone" loading.
The Consequence:
To achieve the same flight feel (solidity and wind penetration) as a heavy pilot, a light pilot often has to load their wing to 100% or more of the range.
Heavy Pilot: Can fly at 75% range and be "Optimal."
Light Pilot: Must fly at 100% range just to avoid being "Floaty."
This is why our calculator might show a small pilot as "Yellow / Light" even if they are legally at the top of their certified weight. The physics of being small puts you at a disadvantage that the certification label does not reveal.
3. The Paradoxes: When "Legal" Isn't "Optimal"
This tool highlights the conflict between Certification (Safety) and Physics (Flight Mechanics).
Scenario A: The "Red Zone" Inside the Weight Range
Example: A student flying a 21 m² wing at 50kg (Certified EN-A).
The Calculator Says: Severely Underloaded (Red).
Why: Even though the manufacturer certifies the wing as "safe" (meaning it recovers well), at this weight, the internal pressure is critically low (< 2.8 kg/m²). The wing acts like a "jellyfish"—it lacks the structural tension to stay open in turbulence and lacks the momentum to penetrate upwind.
The Reality: You are legal, but aerodynamically vulnerable.
Scenario B: The "Green Zone" Outside the Weight Range
Example: A progression pilot flying a 21 m² wing at 5kg over the max weight. ● The Calculator Says: Balanced / Standard (Green).
Why: Physically, the wing is finally pressurized enough to cut through the air effectively. The pilot experiences the "Optimal" flight feel that larger pilots get naturally.
The Reality: You are aerodynamically optimized, but you are flying an uncertified/illegal configuration.
4. Class-Specific Logic
We treat different classes of wings differently because the priorities change as you progress. School & Progression (EN A / Low B)
Priority: Wind Penetration vs. Forgiveness.
The Logic: We penalize light loading here because beginners are most at risk of being blown backward in strong winds. However, we cap the "Green Zone" strictly (at roughly 3.9 kg/m²). Overloading a beginner wing removes the passive forgiveness students rely on, making reactions too dynamic.
XC Sport (High B / EN C)
Priority: Handling & Efficiency.
The Logic: The "Green Zone" is narrower. Pilots need enough weight to control the glider with authority (inputs/weight shift) and keep the nose open on speed bar and in thermic conditions. Light loading here is marked as "Vague" because you reduce the feedback and connection with the wing.
Performance (EN D / CCC)
Priority: Structural Integrity.
The Logic: At this level, flying light is dangerous (cravats/stalls). However, flying too heavy risks Shock Loading. The lines on 2-liners are thin and under immense tension. Overloading these wings risks physical failure of the equipment during an explosive collapse.
5. How to Use the Results
🟢 Green | Optimal You are in the aerodynamic sweet spot. Your wing will perform exactly as the designer intended with solid internal pressure.
🟡 Yellow | Light You are safe, but turning authority is reduced. Feedback feels softer, making it harder to sense thermals. You will struggle to penetrate strong winds compared to your peers.
🔴 Red (Under) | Severe Caution. Regardless of certification, your wing is effectively too large for your weight. Internal pressure is critically low. Avoid strong conditions.
🔴 Red (Over) | Dynamic Caution. You have high kinetic energy. Everything happens faster. Ensure your pilot skills are up to the task of catching impulsive surges.
6. The Evolution of Loading: Class by Class
A common question is: "Why is the Green Zone different for every class?"
The data below, compiled from industry-leading manufacturers (Ozone, Advance, Skywalk, Gin, Niviuk), reveals a clear trend: As performance increases, the required wing loading increases.
Industry Averages: The "Sweet Spot" Shifts Up
The table below represents the average loading across popular wings in each class.
+-------------------+---------+------------+-------+--------------------------------------+
| CLASS | BOTTOM | MIDDLE | TOP | WHY? |
| | (Light) | (Standard) | (Perf)| |
+-------------------+---------+------------+-------+--------------------------------------+
| School (EN A) | 2.8 | 3.3 | 3.9 | Prioritizes low speed for safe |
| | | | | landings & forgiving stall recovery. |
+-------------------+---------+------------+-------+--------------------------------------+
| XC Sport (High B) | 3.2 | 3.6 | 4.0 | Balances thermal float with enough |
| | | | | pressure to glide into the wind. |
+-------------------+---------+------------+-------+--------------------------------------+
| Sports (EN C) | 3.4 | 3.9 | 4.3 | Requires higher pressure to maintain |
| | | | | profile stability on speed bar. |
+-------------------+---------+------------+-------+--------------------------------------+
| Performance (EN D)| 3.7 | 4.1 | 4.5 | High internal pressure is mandatory |
| | | | | to prevent collapse at high speeds. |
+-------------------+---------+------------+-------+--------------------------------------+
| Competition (CCC) | 4.2 | 4.5 | 4.8* | Maximum rigidity. Must be "hard" to |
| | | | | cut through air at 60+ km/h. |
+-------------------+---------+------------+-------+--------------------------------------+Note on Maximums: These figures are averages. Specific high-performance wings often exceed these numbers. For example, while the average top loading for the CCC class is 4.8 kg/m², specific wings like the Niviuk Icepeak X-One are designed to fly at loadings up to 5.0 kg/m². Always consult your specific wing's manual.
A Note on Tandems
Tandems have the widest range (2.8 – 5.4 kg/m²) to accommodate passenger variance.
At 5.4 (Heavy): While high loading increases trim speed and pressure, the glider still suffers from significant parasitic drag (two pilots, spreaders). Even heavily loaded, a tandem retains the glide efficiency of a standard EN B and will not match the upwind glide angle of a modern solo XC wing.
Happy flying,
Grant
P.S. I’m not an aerodynamics expert or a manufacturer, just a passionate guy trying to make a positive contribution. If you have Questions/ Corrections/ Suggestions/ Feedback - please leave a comment below.