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Performance Characteristics of the PD Optimum Reserve
PD Optimum Reserve Information and Flight Characteristics1. Introduction
Performance Designs has built over 35,000 PD reserves, which has a well-earned reputation as a safe, strong
reserve that opens, flies and lands very well. The new Optimum builds upon that great track record. It not only
exceeds the stringent standards of TSO C23d and packs far smaller than any other reserve available, but it also
flies and lands far more like a main parachute. It has the most powerful flare, by a wide margin, of any reserve we
have ever tried.
2. General Information
The Optimum Reserve is a rectangular 7-Cell canopy available in sizes ranging from 99 to 143 square feet. It is
made from a new low permeability, low bulk fabric available exclusively from Performance Designs. We’ve
combined this fabric with special aerodynamics and extensive reinforcing to create great strength, better
performance, and a smaller pack volume for a given size. The Optimum has been successfully test-dropped at
weights and speeds considerably higher than those required for FAA certification according to TSO C23d, the
highest standard to date.
3. A Note on Comparing Canopies
When describing the performance characteristics of a particular canopy, it is important to consider a person’s
frame of reference. Your impression of your reserve’s performance will be influenced by the size and type of
main canopy you normally jump, and by other canopies that you have jumped in the past. Remember that a main
and reserve may have very different flight characteristics, especially if they are significantly different in size.
There are also many additional factors to consider when choosing a reserve parachute, since it is a canopy you
will likely be using only in an emergency. Many of these items are covered in the “PD Reserve Flight
Characteristics” document, and are not repeated here. We suggest you read that document entirely, as well as
the PD Reserve Owner’s Manual for additional safety information.
4. Openings
Sub-terminal openings are generally soft and comfortable, with a short snivel and an even, progressive inflation
that develops from the center to the outboard cells. Terminal openings typically involve light to moderate snatch
forces, with signs of a brief snivel, before progressing into an inflation that is quick but not hard.
During the development of the Optimum, careful attention was placed on minimizing opening forces for safety,
especially in the high-speed spectrum.* Our test jumps also included deployments with several induced line
twists, where we found that the Optimum opened and inflated at generally the same rate. With reasonable body
position, it remained centered overhead with no tendency toward diving or losing additional altitude.
* IMPORTANT NOTE: The FAA requires reserves to be tested beyond their placarded weights and speeds to provide an
additional margin of safety. The Optimum Reserves have been tested beyond the FAA’s minimum requirements to increase
this margin; however, you should NEVER exceed the maximum placarded weight for a reserve, or deploy it at a higher
airspeed than the maximum placarded speed. The deployment time and altitude described in the TSO should not be used to
determine a minimum safe altitude for reserve deployment. You should always perform emergency procedures at or above
the minimum altitude recommended in USPA’s Basic Safety Requirements or according to the recommendations of your
country’s national parachute association.
5. General Flight Characteristics
Glide: The Optimum Reserve has a slightly flatter glide that the current PD Reserve. Descent rate and glide more
closely resembles that of a similar-sized main canopy than other reserves. It does not glide as far as the flatter
gliding models of zero-porosity main, such as the PD Stiletto, but it may out-glide some canopies designed to dive
hard and long after a turn.
Turns: The Optimum has overall crisp response to control inputs. The Optimum feels very similar in toggle turns
to the standard PD reserve of the same size. Keep in mind that the smaller the canopy, the more bank angle will
be required to make a turn at a given radius. Like most 7-cell canopies, the Optimum Reserve is very responsive
when turning in braked flight. You can lose less altitude when turning an Optimum Reserve in brakes, but give
yourself plenty of altitude to make your last turn, especially on a small canopy!
Control Range: The Optimum has a fairly long control range for a reserve parachute, longer than the standard
PD reserve, with excellent slow flight characteristics. The stall point is very deep for a reserve, so much so that it
may be possible to fly at full arm extension for a few seconds prior to getting a stall. Of course, the exact stall
point of any canopy depends on the canopy size, riser length and arm length. Recovery from an induced stall is
quick and clean. Altitude permitting, it is best to check the control range and stall point of the Optimum prior to
landing, because the stall point will probably be very different from that of your main.
Stalls and other radical maneuvers should obviously be avoided close to the ground.
Recovery Arc: The Optimum Reserve has a similar recovery arc to the standard PD reserve. This means it
recovers quickly from a dive, compared to a canopy like the Velocity or Katana. Other main canopies, such as a
Stiletto, may have a quicker recovery arc. It is important to remember that a canopy’s recovery arc is also
affected by wing loading: a higher wing loading generally causes the recovery arc to become longer.
Landings: We’ve always been proud of the excellent flare performance of the current PD reserve compared to
other reserve canopies available, but the Optimum Reserve is even better by a wide margin. Landing
performance and predictability more closely resembles that of a main parachute.
The canopy responds immediately to proper flare input, providing ample feedback to the jumper. The “sweet spot”
in the flare is easy to find, starting around mid stroke, and is well above the stall point. A properly timed flaring will
cause the Optimum to plane out easily, better than other reserves and similar to many main canopies.
With the long control range and powerful response, it is relatively easy to land well, with timing of the input being
less critical than for other reserve parachutes of similar size. However, these great landings are not automatic.
You must have the skill and technique that is appropriate for the Optimum size you have selected. Any small
canopy will have a high descent rate on final, so flaring must be timed well. Regardless of how great the flare
potential is with the Optimum, a hard landing will be the likely result from a poorly timed flare. If your first Optimum
ride is in a real emergency situation, you are likely to be at a lower altitude than normal, and may not have much
time to practice flaring or explore the canopy’s other flight characteristics. Your adrenaline level may also be
slightly higher than normal. All of these factors should be considered when choosing the size of your reserve.
6. Reserve Sizing
There are several factors to consider when choosing the size of your reserve. The most important factor to
consider is the maximum exit weight limit for a particular size. Many jumpers exceed the maximum weight limit
for their main canopies. While this may be foolish, it is not illegal. The maximum exit weight for a reserve is a
legal limit. In the United States, it is a violation of federal law to jump a reserve if your exit weight exceeds this
limit, and other countries may enforce this limit as well. The maximum exit weight is published on the Warning
Label sewn to the tail of every Optimum Reserve, in the PD Series Ram-Air Reserve Owner’s Manual, and in the
product information on our web site.
Even if you are a highly experienced skydiver, you need to be cautious if you plan to jump with a small or highly
loaded reserve. We recommend a minimum of at least 50 jumps on a canopy no more than 15% larger than the
Optimum reserve you plan to use. There are additional skill and experience requirements that must be met
if your wing loading will be greater than 1.4 lbs./sq.ft. These requirements are listed in the PD Series Ram-
Air Reserve Owner’s Manual, along with additional information about reserve sizing, wing loading, and their
effects on a reserve’s performance.
If you have a high exit weight and fly a highly loaded main canopy, you may need to choose a larger reserve to
stay within the reserve’s weight limits. However, in most cases it is best to choose a reserve that is close to the
size of your main. If your reserve is more than 15% smaller than your main, there will probably be dramatic
differences between the canopies’ flight characteristics. In the mid-1990’s PD conducted a series of tests to
investigate dual-square situations, where both a main and reserve were open at the same time. We found that
these situations are usually easier to handle when the main and reserve are similar in size. The results of these
tests were published in the Dual Square Report, which can also be found in the Education section of our web site.
The best way to find out how any canopy performs is to jump that specific size and type of canopy. Performance
Designs has demo Optimum Reserves available, allowing you to find out how a certain size will fly and land
before you buy it. Our demo Reserves are identical to actual Optimum Reserves, except they are attached to
main risers and built with pilot chute attachment points so they can be jumped as main canopies (since Optimum
Reserves were designed specifically to be used as reserves, they normally do not have pilot chute attachment
points).
7. Optimum Reserve Sizing Chart
The weights listed below are the MAXIMUM weight limits for each category and size. There are many reasons why you might wish to stay
below the maximum limit for your canopy. It is perfectly acceptable for your weight to be below these limits, as long as wind and landing
conditions permit.
|
MODEL |
SHIPPING WT. |
AREA (SQ. FT.) |
Skill Levels/Operating Limits |
SPAN (FT.) |
CHORD Center/End (FT.) |
ASPECT RATIO |
|||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Min (Lbs.) | Novice (Lbs.) | INT (Lbs.) | ADV (Lbs.) | Expert (Lbs.) | Max (Lbs.) | ||||||
| Optimum Reserve 99 |
6 lbs. |
99 | VLC | N/R | N/R | 119 | 149 | 220 | 14.42 | 6.87 | 2.1:1 |
| Optimum Reserve 106 |
6 lbs. |
106 | VLC | N/R | N/R | 127 | 159 | 220 | 14.92 | 7.10 | 2.1:1 |
| Optimum Reserve 113 |
6 lbs. |
113 | VLC | N/R | N/R | 130 | 169 | 220 | 15.40 | 7.30 | 2.1:1 |
| Optimum Reserve 126 | 7 lbs. | 126 | VLC | N/R | N/R | 145 | 176 | 254 | 16.27 | 7.75 | 2.1:1 |
| Optimum Reserve 143 | 7 lbs. | 143 | VLC | N/R | 122 | 165 | 200 | 254 | 17.33 | 8.25 | 2.1:1 |
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