The wing

The wing was optimized, calculated from ground up with the help of a research institute and two universities. It incorporates a new thin 13.2% airfoil that is modified in order to reduce the influence of insect contamination. At the root section the wing goes up to 16.4% thickness and meets the fuselage with a refined transition shape. The wing has a special planform with elliptical swept leading edge and special 3D shaped state-of-the-art wingtips, which were optimized to lower the induced drag of the whole wing. The trailing edge incorporates a three section flaperon along its whole length. This configuration brings the pilot friendly behavior and improved flight characteristics.

Stiffness of the wing was optimized using FEM calculation in combination with break tests. The result is a carbon fiber structure providing comfort during cruise, maximum sensitivity for both strong and weak thermal lifts and friendly flutter characteristics.

To achieve the highest possible precision and best surface finish the wing was fully computer designed and the moulds were produced with the very latest 5axis CNC technology.

The water ballast is directly in integral tanks allowing the wing to house up to 250 liters of water. Other ballast tanks are in the tail and optionally in the fuselage. Maximum take-off weight of the 18m version is 600 kg, maximum wing loading 50.8 kg/m² and the gliding ratio raises over 51 at 125 km/h.

Aerodynamically shielded wingtip wheels make the take-off and landing easier and trouble-free and are highly rated by the pilots.

For a better descend control at landing three-flange aerodynamic brakes were introduced.

Assembling the wings with the fuselage is very easy, connection of control surface drives as well as water ballast drive is done automatically. Same features shows the wing extension assembly. Securing the extensions is done trough a single bolt, connection of the flaperons is also automatic.

Wing tip and wheel

3-flange aerodynamic brakes

Flaperon drive cover

The tail

The T-shaped tail combines well-proven design with the best possible technology. Elevator and rudder are made with high precision carbon fiber prepreg technology to achieve low weight while keeping high stiffness. Ending tips of the stabilizer have a state-of-the-art shape to raise its efficiency while cutting down the induced drag. Elliptical planform of the stabilizer is a matter of course. Assemblage of the horizontal surface with the vertical is a question of seconds, elevator connects automatically and securing is done by a single pull pin.

Stabilizer connection system

Shaped stabilizer tips

Hi-tech prepreg elevator (used on the prototype)

The fuselage

In keeping with the Glasflügel heritage, innovations in the fuselage introduce a new safety cockpit far beyond the standards. Made mostly of carbon fiber with wide use of carbon-aramid hybrid composite the cockpit proved an extraordinary ability to resist impact damage. Numerous FEM calculations, break tests and simulations of impact behavior resulted in a design that can save life to its pilot. “Roger hook” as a standard feature for safe jettisoning of the canopy is integrated in the massive frame.

The middle part of the fuselage is primarily adapted for housing an engine. The motorization program counts with three different engine systems: self launcher, “turbo” sustainer and JET engine. The engine bay and place for fuel tanks are universal for all three systems and are part of the primary structure. Installation of engine can be easily done according to customers demand and can also be done additionally.

Integrated Roger hook

Fuselage structure is prepared for engine installation

Highly effective TBS 400N jet engine - Turbo variant 304SJ

Piston engine (Walter Binder) - selfstart variant 304MS

The cockpit

Comfort in the cockpit has always been one of the main trademarks of Glasflügel sailplanes. The safety cockpit of the 304S has been completely redesigned. Serious design and ergonomic studies have been done to assure perfect seating and view from the cockpit. Every pilot knows how important a feeling of comfort and safety is during the flight. These features were stressed by using materials of the highest quality. Enjoy the massive carbon-aramid frame, prestigious and durable leather interior, well-arranged instrument panel and friendly controls! Every detail has been designed with a special care, check the control-stick handle, canopy lock mechanism or the ventilation outlet! Enough space for elbows and shoulders makes a perfect seating even for taller and heavier pilots. Custom rearrangements are possible of course.

The 304S is equipped with a spring-loaded and damped landing gear. Double action telescopic frame with rubber shock absorbers in combination with large 5” wheel allows cushion like landing even on a rough field. Hydraulic brake guarantees rapid brake action.

Main Wheel with suspension and hydraulic disc brake