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4. Construction and development of the “Duke”:
The “Duke” consists of 56 cells, of which every third is attached to a line. The V-bands ensure that the
load on the line attachments is spread onto the adjoining ribs. This results in fewer lines without loss
of airfoil shape, whilst maintaining profile integrity, and canopy stability. The resistance of the lines in
the air is thus reduced as well as providing easier sorting of the lines before take off.
We have used the best and up to date technical equipment to develop the “Duke”. 3D models were
built on the computer and tests were simulated before production. All parts are tailored by
computerised cutting machines and printed with inscriptions. Our development team has more
than 15 years of experience in developing and producing paragliders and are supported by
experienced test pilots.
For computer freaks: We use a P3 multiprocessor workstation with two monitors. The cutting
plotters are controlled by a SGI workstation. Our FlyCAD2000 program was specially developed
for paraglider construction, is written in C++/Arx and is updated regularly. It is now used by
nearly all other manufacturers. The “Duke” is a new milestone in the field of acro-gliders.
5. Material Data:
The canopies of our paragliders are made of Porcher Marine Skytex Ripstop Nylon material with an
E77 coating. A filament net is woven into this material which prevents ripping and increases the
tensile strength along the seams. The polyurethane coating makes the material water proof and UV-
resistant. The material used for the lines is Edelrid HMA Aramid, these are made of a special Aramid
formula and have been tried in multiple snapping and load tests.
6. Technical Data:
Size acro
Size factor % 100
Surface area flat m² 19,29
Wingspan flat m 10,51
Aspect ratio A/R 5,72
Weight kg 5,0
Number of cells No. 56
Take off weight min. Kg 65,0
Take off weight max. Kg 105,0
DHV Kat. No certification!
7. How to check your paraglider:
Every paraglider delivered is tested and measured by us. Nevertheless we advise you to check your
paraglider for the following criteria. You should also follow these instruction after a long intensive
flight or an accident on landing, eg: tree landing.
Check:
the seams where the lines attach, and the canopy for any damage.
that all the lines have been sewn correctly and are free of damage
that all the line locks have been screwed up properly and the plastic inlets are tight
that all ribs and V-attachments are free of rips
Every fault no matter how small must be checked and repaired by a professional. A damaged
paraglider is not air-worthy.
8. Steering/brake lines
The two steering/brake lines lead up to a line cascade which is fixed to the trailing edge. On the
risers the steering lines run through a pulley and are connected to a handle. These handles are
fixed to the risers with a push button when not in use. The length of the steering lines is set
correctly at the factory. They have to have at least 5cm of free play and must only be adjusted by
a qualified flying instructor or the dealer. The improper adjustment of the steering lines can cause
severe changes to inflight behaviour.
9. Inflight:
The following pages are not intended to describe how to fly a paraglider. Rather we want to show you
the Duke’s specialities and give you important information regarding in-flight behaviour.
9.1 The harness:
The Duke has been developed with the GH harness. Nearly all harnesses recently produced are
type GH harnesses. They differ from the GX harness due to their low suspension and not very
effective (if at all included) cross straps. Cross straps have not proven themselves in combination
with new paragliders. The last authorisation of a GX harness by the DHV was in 1997. The use of a
fixed cross fixture is inadmissible. The easiest way to check the harness is via the DHV website.
Here the GH or GX harness type is stated.
9.2. Take off preparation:
Before every take off the paraglider must be checked visually for possible damage.
The easiest way to take off with the Duke is to lay it out in an arc so all A-lines are under the same
tension. We generally advise using just the middle A-risers, but using all risers is not a problem. In
flat take off areas you may need to take two steps before the lines come under tension. In other
circumstances we advise tensioning the A-lines lightly. The most important issue whilst launching
the glider is not the force used, but applying a constant pull. The Duke is very easy to launch, but
you may need to brake slightly in stronger wind conditions or steep take off areas to prevent the
wing over-flying.
9.3. Take off run:
During take off the Duke shows no peculiarities. When launching in stronger winds, you can avoid a
premature take off by moving under the paraglider whilst launching it. The best way to train for taking
off in strong wind conditions is by regular ground handling practice.
9.4. Level flight:
With loose steering lines, depending on the wing loading, the Duke reaches a flying speed of 40 to 45
km/h. In calm conditions the Dukeflies at minimum speed if the pull on the brake lines is approx. 30 - 35
cm. In turbulent air we advise flying with the brakes pulled down 5 - 10 cm. The angle of attack is higher
and this makes the wing more stable.
All measurements are relative to the brake lines under no tension.
gliders for real pilots
independence
www.independence-world.com
gliders for real pilots
independence
www.independence-world.com
