MAN-0012 Rev. I
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SECTION 2
CHOOSING THE CORRECT RESERVE SIZE
Performance Designs reserve canopies are built in different models that span a wide range of sizes
and operating limits. There is a specific reserve to match almost any combination of deployment
altitudes, weights, skill levels, and landing elevations. When selecting a reserve there are certain
factors to take into consideration. Some of these are legal limits that must be respected.
It is important for your safety and enjoyment that you match your canopy with your ability and
weight.
If a canopy is too small for you, safe and comfortable landings will be difficult to obtain,
even for experienced jumpers under ideal conditions. Less experienced jumpers should be more
conservative on canopy size.
The explanations about canopy flight characteristics below are based on landing elevations at sea
level. If you’re landing at elevations of more than 2000 feet above sea level, you should
consider getting a canopy at least one size larger than what you would normally jump
at sea level.
Determining the wing loading of the parachute you intend to jump or buy is a good guide to
matching your weight to a particular canopy. Wing loading is easily calculated by dividing a
total suspended weight in pounds by the surface area of the parachute in square feet.
Total suspended weight is the weight of the jumper plus all his/her clothing and gear, including all
components of the parachute system.
For example, a jumper who weighs 165 lbs (74.8kg) with his/her jumpsuit on and who jumps a
packed rig that weighs 25 lbs (11.35kg) would have a suspended weight of 190 lbs (86.1kg).
Here’s an example of how to calculate wing loading of a 210 square foot canopy and the jumper
used in the example above:
190 lbs
210sq.ft
= 0.9 lb./sq.ft.
Compare the wing loadings of your main and reserve parachutes. Generally, if the wing loadings
are similar and the canopies are both of reasonably similar design, the speeds and skill level
requirements will be close enough for most experienced jumpers to handle. Always keep in mind
that your reserve may handle and fly quite differently than the main you are used to.
Another factor to consider is the wing loading that you are used to flying. This is particularly
important when downsizing your main canopy. Downsizing a canopy usually means that this is
highest wing loading a jumper has experienced. If the reserve canopy is even smaller than the
newly acquired main canopy and therefore an even higher wing loading, this can be a dangerous
situation. Often times when we need to deploy our reserve it is at a lower altitude and there is a
good chance you may not make it back to the landing area. A canopy that is too small may feel
very fast, or have a high rate of descent, and can be tricky to flare. This situation can be very
dangerous, therefore we recommend restricting a change in any wing loading to less than 15%.
With higher wing loadings comes a lower margin for error and a smaller time window for decision
making.
