Wing-loading is a number indicating the load per unit of surface of a parachute. The USA being the biggest market and using the imperial system it’s most of the time expressed in Pounds per square feet (lbs/ft² or lbs/sqft).
You can calculate yours easily by dividing your exit weight (your weight with all your equipment) in pounds by the size of your canopy in square feet.
WL = Weight (lbs)/ Size (sqft)
The size of parachutes is usually expressed in square feet but if you only know your exit weight in kilograms it’s not much more complicated, you just need to convert it to pounds using a 2.2 factor.
WL = Weight (kg) *2.2 /Size (sqft)
This number is important because it defines the way a parachute will behave. Lightly loaded, for example around 1 (also written 1:1 sometimes), a parachute will fly slowly, not dive much during a turn and recover fast after it. It’s a good number for beginners. When wing-loading increases, the parachute tends to fly faster but is also more sensitive on inputs and requires more and more experience to by piloted safely. It is not uncommon to see wing-loadings above 3 in canopy piloting competitions or during XRW jumps, but landing such heavily loaded parachutes requires a lot of dedicated training.
It’s important to know your wing-loading and, when buying a new parachute to make sure you choose a size that is not too different from what you are used to.
Most models of parachutes on the market have a minimum and maximum wing loading. For example, on a Crossfire 3, we recommend a wing loading between 1.4 and 2.0. Under the minimum, it’s usually safe but we haven’t tested it and a less aggressive model might be a better choice. Above the maximum, the openings might become too hard and landing might become tricky.
We offer a full range of parachutes for wing-loadings from 0.8 to 3.0