Enter exit weight and canopy size to get wing loading in lb/ft², or set a target loading to get the canopy
size that produces it. USPA SIM 5-3 and 6-10 are quoted in full below.
Wing loading
Wing loading is your exit weight divided by canopy area - how much weight each square foot of nylon carries. It
is the single number that most determines how a canopy flies.
Wing loading (lb/ft²) = (jumper weight + gear weight, in lb) ÷ canopy size (ft²)
Exit weight means everything that leaves the aircraft: you, the rig, the reserve, the AAD, helmet, camera,
weight belt and clothing. Leaving gear out is the most common way to under-report a loading. The equipment field
here defaults to 14 kg; weigh your own rig rather than trusting the default.
Raising wing loading, with everything else held constant:
- Descent rate increases - less time under canopy and a faster arrival.
- Forward speed increases, so the canopy penetrates wind better and lands longer.
- Glide ratio falls, so you cover less ground per foot of altitude lost.
- Turn rate increases and recovery from a turn takes more altitude.
- Landing arrives faster, and the window for a mistimed flare gets shorter.
What this number does not tell you:
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Canopy design matters as much as loading. A 1.2 lb/ft² elliptical and a 1.2 lb/ft²
nine-cell student canopy do not fly alike.
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Density altitude shifts the result. A high, hot dropzone gives a true airspeed higher than
the same loading at sea level.
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Currency matters. The USPA bands below assume recent jumps on the canopy in question, not a
logbook total.
Downsizing is a decision to make with an instructor or a canopy coach against your own logbook and the
conditions you actually jump in. This page computes; you decide.
USPA SIM Reference
5.3 Main parachute
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Jumpers should choose canopies that will provide an acceptable landing in a wide range of circumstances, based
on several factors including canopy size, wing loading, planform (shape), skill level, and experience.
- Owners should verify with a rigger that all applicable updates and bulletins have been accomplished.
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Jumpers should observe the recommendations of the canopy manufacturer for the correct canopy size, usually
listed by maximum recommended weight with respect to other factors:
- the jumper's experience
- drop zone elevation
- other conditions, such as density altitude
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Wing loading, measured as exit weight in pounds per square foot (psf) provides only one gauge of a canopy's
performance characteristics.
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A smaller canopy at an equal wing loading compared to a larger one of the same design will exhibit a
faster and more radical control response, with more altitude loss in any maneuver.
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Design, materials, and construction techniques can cause two equally wing-loaded canopies to perform very
differently.
- Different planforms (square vs. elliptical) will exhibit very different handling characteristics.
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The Minimum Canopy Recommendations chart represents the minimum recommended canopy size by exit weight and
total jumps made on solo equipment with square parachutes. Canopy size for students is at the discretion of
the instructor.
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Due to the varied sizes of canopies from different manufacturers, any canopy less than 3% smaller than the
listed recommendation is acceptable.
- Canopy choices for jumpers over 1,000 jumps is at their discretion.
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These minimum canopy recommendations may be too aggressive for some jumpers and, in other cases, too
conservative. Instructors, canopy coaches and drop zone leadership should assist their skydivers in
selecting an appropriate canopy for their jumper's ability and progression.
6.10 Canopy Flight
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“Advanced” refers to practices that combine equipment and control techniques to increase descent and landing
approach speeds.
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A canopy designed for more performance may exhibit relatively docile characteristics with a light wing
loading and when flown conservatively.
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A canopy designed for docile performance that is flown aggressively and jumped with a higher wing loading
can exhibit high-performance characteristics.
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The types of errors that novice canopy flyers make on docile canopies without getting hurt could have serious
consequences when made on more advanced equipment.
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Advanced equipment generally refers to canopies loaded as follows:
- above 230 square feet, 1.1 pounds per square foot or higher
- from 190 to 229 square feet, 1.0 pounds per square foot or higher
- from 150 to 189 square feet, .9 pounds per square foot or higher
- canopies smaller than 150 square feet at any wing loading
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Canopy design can play a significant role in skewing these numbers one way or the other.
- Some canopies are designed for flaring with less-than-expert technique.
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Some canopies are designed to perform better with higher wing loadings but require skillful handling.
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Earlier canopy designs, particularly those using 0-3 cfm canopy fabric (“F-111”), can be more challenging
to land, even with relatively light wing loadings.
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Advanced technique generally refers to control manipulation to induce speeds greater than stabilized,
hands-off, level flight (natural speed) during descent and on the final landing approach.
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Canopy flight characteristics and control become more challenging as field elevation, temperature, and
humidity increase.
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These recommendations do not consider the specialized information and expertise required to safely fly
canopies at wing loadings approaching 1.5 pounds per square foot and beyond or canopies approaching 120 square
feet or smaller.
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Each progressive step in downsizing, technique, and canopy design should be a conscious decision, rather than
considered a routine part of a skydiver's progression:
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Jumpers downsizing to get a smaller or lighter container should also be prepared to handle the added
responsibility of jumping a higher-performance canopy.
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Jumpers at drop zones with a high-performance canopy culture need to understand that neglecting the
individual training required to pursue that discipline safely can lead to serious consequences for
themselves and for others.
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Jumpers need to understand the design intents of the canopies they purchase to see whether those canopies
match their overall expectations and goals.
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The decision to progress to advanced canopy skills and equipment should include others who can be
affected, including jumpers in the air and landing area who could be affected by a canopy piloting error.