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Wing loading calculator

Wing loading—exit weight divided by canopy area—has important effects on canopy flight characteristics. Generally speaking, a higher wing loading means all of the following: higher descent rate, higher stall and landing speeds, longer landing distances, less sensitivity to turbulence and wind drift, reduced low-speed maneuverability. A lower wing loading generally means the opposite: lower descent rate, lower stall and landing speeds, shorter landing distances, increased sensitivity to turbulence and wind drift, increased low-speed maneuverability. As a rule, flying at higher wing loadings requires more experience, but wing loading is only one performance parameter among many. Canopy size, planform (e.g. how tapered), trim and construction all contribute to how a canopy flies; two canopies at the same wing loading can handle quite differently. The physics of this tool is explained in the altitude types article.

Jumper and canopy parameters

Density altitude effect

Downsizing charts and manufacturers’ recommended wing loadings generally assume sea-level air, so this tool compares today’s conditions against a standard sea-level day in the International Standard Atmosphere (ISA). Density altitude is always present in our atmosphere and also has important—often neglected—effects on canopy performance, effectively changing the way a canopy with the same wing loading performs; thinner air makes a canopy fly like it is more heavily loaded and thicker air makes it fly like it is more lightly loaded. You can use the sliders below to set current conditions, or pull the current observation from your dropzone’s airport, to see what effect today’s conditions have on the wing loading shown above.

How it works. Wing loading is exit weight (weight when fully geared up) divided by canopy area, conventionally expressed in lb/ft²—a fixed number that does not change with the weather. Air density comes into play through canopy aerodynamics: flying at the same angle of attack, true airspeed scales with the square root of wing loading divided by air density—so thinner air drives the same canopy to the speeds a higher wing loading would. The second figure is comparative, referenced to a standard sea-level day: the wing loading that would fly these same speeds in that air. It matches airspeeds, not forces—on a hot day your canopy is not more heavily loaded, it is flying faster. Density altitude is calculated using the full three-step form, the same used in our density altitude calculator (your conditions carry over). Current weather is the latest METAR observation from NOAA’s Aviation Weather Center—an observation; we never use a forecast in these tools.

This tool is provided purely for informational purposes and makes no recommendations regarding canopy choice. Nothing here is a substitute for proper training by certified instructors. See, for example, the United States Parachute Association's Integrated Student Program, described in the Skydiver's Information Manual; for more advanced canopy-flight instruction, see, for example, AXIS Flight School.