Dudek Snake, User Manual

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retain features of a classic paraglider, the application of a reflex aerofoil
section added several new qualities. First of all, using that profile means that
the wing stability does not depend exclusively on the pilot. It maintains a
stable pitch attitude, rising and sinking through thermals while remaining
stable above your head, without need for so much pilot input.
Generally speaking, the reflex profile is a special kind of aerofoil section. The
specific static pressure distribution creates a situation where at low attack
angles only the fore wing part (some 60% of the chord) is producing lift, while
rear 40% of the chord creates an effective stabiliser against excessive
decrease of the attack angle.
The trimmer system allows for considerable raising the rear part of the airfoil,
thus effectively reducing its projected chord and surface area by some 15%,
giving the paraglider a higher wing loading and increasing its speed. The
centre of pressure also moves forward, adding enhanced pitch stability. Such
shift of loading gives the Snake XX an exceptional tuck-resistance and
increases its projected aspect ratio, resulting in much better performance
especially at high speeds.
Reduced „reflexivity” of the Snake XX (on closed trims) is in part
compensated by its smaller size at maximum take-off weight, possible due to
increased wing loading factor.
2.2 STRUCTURE
The body of the Snake XX was designed in our CSG (Canopy Shape Guard)
system, comprising many elements resulting in exceptional coherence and
stability of the shape. Below you will find a short description
of CSG subsystems.
Snake XX has an elliptical planform with slightly rearward
swept tips. The cells are divided with ribs additionally
supported by diagonal
VSS (V-shaped supports) system.
Such arrangement ensures a smooth top surface, exact aerofoil reproduction
across the entire wingspan and yet more importantly, better load distribution
and minimal number of suspension points.
The lower surface has a RSS (Reinforcing Strap System) applied inside the
canopy. RSS is a ballooning-independent reinforcements system, made
entirely of paragliding fabric, stiffening and stabilizing entire canopy structure.
Snake XX’s aerofoil is another product of our DRA (Dudek Reflex Airfoil)
technology. It was calculated with our previous
experiences in mind and thoroughly tested with
numerical methods. It is a reflex aerofoil, with all its
properties described above.
The suspension points areas are additionally reinforced
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