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| Canopy Setup and Maintenance | Go to:Maintenance |
Soft Links
We totally recommend the use of soft links, not only will
they make your slider easier to drop down they will be easier to pack with and
increase the life of your line set. Most riggers will install soft links for you
for a small fee.
Collapsible Pilot Chutes
Using a collapsible pilot chute will improve the performance
of your canopy. The increase in performance you will gain depends on the size of
the canopy and the wing loading. It is a balance between the two rather than
wing loading or canopy size as the pilot chute size generally remains constant
rather than reducing with the canopy size.
There are two types of collapsing systems in common use, the
Kill line system and the Bungee system. We prefer the Kill line however the
Bungee is easier to operate and requires less packing.
If you are using a class 3 or below (below 1.25 PSF) or
canopies above 160 square feet this gain will be minimal and possibly not worth
the complication (like in a student canopy situation).
For Class 4 (1.25-1.65 PSF) or canopies between 160 and 120
square feet we recommend a collapsible pilot chute. Either a Bungee system or a
Kill line is OK.
For Class 5 and above (above 1.65 sf) and canopies below 120
square feet it is pretty much a necessity. This situation should be used with a
Kill line rather than a Bungee as the speeds you can reach are leaving a smaller
range between a subterminal opening and a hell canopy swoop.
On small canopies collapsing the pilotchute has a double
effect, first the drag of the pilot chute has gone and secondly when the pilot
chute is inflated it will drag the center of the canopy back putting a slight
"V" in the canopy planform. This "V" configuration increases
the canopy drag considerably as the flow of air is no longer running directly
down the cell (which is relatively smooth) but at an angle across it (which is
very rough due to the cells bulging between the ribs). Imagine the cross section
of a canopy at any point then imagine the cross section 10 degrees off true and
you will understand the need for a collapsing pilot chute in this situation.
Another effect an inflated pilot chute has is to reduce the
canopies recovery arc. On a highly loaded canopy with a large recovery arc it
may reduce the arc be as much as 30% by pulling the canopy up short and not
letting the canopy dive for very long. This becomes especially relevant in two
situations. 1) If you have been flying your canopy with an inflated pilotchute
then put a collapsing system on you will need to increase the height of your
hook turn as your canopy will be diving more and require more time to recover (a
potentially dangerous trap) you will also be coming in faster horizontally as
your canopy will have accelerated more through this longer recovery arc and
through less drag (it will behaving like a smaller canopy). 2) If you are using
a Bungee system that may or may not stay collapsed during your swoop you have
now lost control of the height that your recovery arc will level out at,
especially a problem if your pilot chute has been inflating behind you without
you knowing.
Dropping the Slider
Collapsing and lowering the slider behind your head as well
as releasing some tension from your chest strap is of some benefit also.
Although not providing as much gain as a collapsible pilot chute it can add some
extra performance as well as changing the feel of your canopy quite a bit. By
lowering and collapsing the slider it will have 3 effects.
- The drag from the slider will be greatly reduced.
- The canopy will produce more lift upwards. With the slider sitting at the connector links it is restricting the spread of the canopy slightly increasing the anhedral arc, this means the outside edges of the canopy are not sitting as flat and the lift generated by the wing tips is vectored further from the vertical thus reducing the overall lifting power of the canopy.
- Any twisting between you and the canopy will be reduced. The load from the lines that was running into your slider and chest strap and out to your hips is now running straight from the canopy to your hips which are wider and more securely attached to you than your chest strap or slider. As you turn your canopy your body will tend to move with the canopy as one unit rather than being left behind in the turn to catch up.
Again all these effects are felt more when the wing
loading is higher as lift and efficiency become more important and our turns can
become much faster.
If you are using a class 3 or below (below 1.25 PSF) this
gain will be minimal and possibly not worth the complication (like in a student
canopy situation).
For Class 4 (1.25-1.65 PSF) we recommend a collapsible slider
but the chest strap gain is minimal.
For Class 5 and above (above 1.65 sf) it is pretty much a
necessity to do both, the performance and feel of the canopy will both improve
noticeably.
To drop the slider you must have 25mm (1") risers and
either soft links or #3.5 SS links that we provide with the canopy.
The best technique for dropping the slider is
- Open and check your canopy, do not release your breaks.
- Grab the rear risers and steer the canopy towards the DZ and clear from other canopies.
- Making sure you are clear of other canopies reach up and using your first two fingers above the grommets slide the rear slider grommets over the links, break settings and toggles.
- Grab the slider in the center and pull it down, it will come easily over the front risers.
- Collapse and stow the slider. We have the option of 2 collapsing systems available on our sliders, the Velcro wrap and the draw cord.
The Draw String can be simply pulled down and pulled tight
then thrown behind your head. This system is easy to operate but does not
collapse the slider as well.
The Velcro is best used with a piece of 25mm hook Velcro sewn vertically on the
collar of your jumpsuit, Fold the Velcro tail over the hook on the slider for
packing as to leave a tail that is easy to grab, after opening pull the slider
down and in front of you and twist it several times, tear off the tail and stick
it on your collar. This method collapses the slider more to provide more
visibility and less drag but is harder to use.
- Pop the chest strap, pull the adjuster back and away from you with your fingers until the chest strap stops moving or is almost against the stop (only do this if there is a stop) some of our customers have ordered rigs with extra long chest straps to help spread the canopy. Do not release the chest strap completely as there will be nothing stopping you falling forwards out of the harness. Also be aware that if you cut away (say in a canopy collision situation) your handles will be in different positions and your harness will be slack.
- Release your brakes.
At first this whole process might take you half your
canopy ride but with a little practice you will have it down to 10-20 seconds.
The most important thing we can stress here is not to loose awareness of other
canopies or the DZ while you do this, it is hard to watch where you are going
and stow your slider and there is likely to be others in the area doing the same
and not looking out for you. Keep glancing around while you are doing this
checking for other canopies and the DZ location, the canopy can be steered quite
well on rear risers.
Tube Stows
Many people are anti Tube Stows for a variety of reasons, we
watch a lot of people using tube stows in the field successfully without any
problems. We have also seen people having opening problems then solving them
through the use of rubber bands. If you are using tube stows successfully then
keep going however if you have or develop inconsistent openings try tight rubber
bands for a while.
Line Dump
Line dump occurs when the line stows are short enough and
loose enough to allow the lines to drop from the bag during the snatch of the
bag lifting off your back. This may cause bad openings or increase the chances
of malfunctions due to out of sequence line deployment. In the worst case the
locking stows may dump or more commonly break and dump the canopy from the bag
before line stretch. To reduce the chances of this happening keep a good eye on
your stows and replace any worn stows as well as keeping your stows tight and
line bites a good size.
Pack Volume
The pack volume of your canopy will reduce slightly over the
first 20-40 jumps as the fabric softens through use. At the same time the
coating that is on the fabric will become less slippery. After the canopy has
been used a little you may find it much easier to pack than when brand new.
| Maintenance | Canopy
Setup |
General
Apart from the line set (We'll talk about this next) your
canopy should require very little maintenance. You should give your canopy a
visual inspection approx. every 100 jumps or possibly get your rigger to do it
during your repack cycle. Look for tears in the fabric burns around the slider,
stabilizers, bridle attachment and tail as well as broken stitches. The other
main things to look for are damaged or rough slider grommets and loose connector
links or damaged soft links
Line Trims
Spectra line goes out of trim over time. Some lines will
shrink and some may stretch. Stretching is mostly caused by loads on the line
pulling the weave closer together and shrinkage is caused by heat as the slider
runs up and down the lines at high speed. Unfortunately the lines with the most
load on them are the lines in the front in the center of the canopy and the
lines that take the most wear and heat from the slider are the outside lines so
they do not go out of trim evenly. As the canopy goes out of trim the front
center of the canopy will lift up and slightly change the canopies overall angle
of attack. As this happens over hundreds of jumps you will more than likely not
notice this too much. Your canopy has actually been trimmed from the factory to
allow for this slightly and so as it gets a long way out of trim it remains
useable.
The problem is that which lines stretch or shrink at what
rate is unpredictable. We have seen canopies that have been over 100mm out on
some lines still performing acceptably. We have also seen canopies develop
problems only 40mm out of trim that have been solved by retrimming. If your
canopy is opening, landing and stalling without a noticeable drop of in
performance or bad characteristics we suggest letting any one line getting up to
60mm out of trim for canopies below 115 square feet and 70mm for canopies above
115 square feet before retrimming or relining. If your canopy is not performing
as it should and any one line is more than 30mm out of trim then in this
scenario also retrim or reline the canopy.
Line Sets
On a Zero-P canopy, the canopy will generally outlast the
lineset by several times that of Spectra line which has a limited life and will
generally need replacing anywhere from 300-600 jumps for 500 lb. line and
500-1000 jumps for 725 lb. line. The life of your lines will depend on several
factors like your weight, the cleanliness of your packing environment, the
number of lines (7-Cell or 9-Cell), how well you look after them and the
condition of your slider grommets. Linesets should be monitored for wear and
trim and retrimmed or replaced as you would a set of tires on a car. The things
to look out for are trims, wear spots, snags and worn stitching. Often wear
spots can appear quite bad but still retain much of their strength (such as wear
by Velcro) and sometimes a line can appear in quite good condition and be
weakened considerably (often underneath a fingertrap). A simple test is to
squeeze the line between your thumb and finger and slide it along, if the line
or wear spot gets thinner it is more than likely weakened. Other common wear
spots are the lower brake lines and the corner lines where they meet the
connector links. You can monitor the condition of your lines easily while
packing, about every 50 jumps have a closer look, If you are unsure of something
check with your rigger. One of the best things you can do to improve the life of
your lines is to use soft links and monitor the condition of your slider
grommets.
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