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Document No.: 304S/MM
Date of Issue:
08/14
1-2
H
P
H
Ltd.
1.2 Technical Description
The
GLASFLÜGEL 304 S
is single seat 18m flapped sailplane of 18m FAI
class, constructed from fiber-reinforced plastics (FRP), featuring camber-
changing flaps and a T-tail (with fixed horizontal stabilizer and elevator)
1.2.1 Fuselage
The fuselage tapers behind the wing, the faired-in one piece canopy is hinged
forward. Canopy jettison mechanism incorporates the Rögger pivot hook.
The fuselage shell is pure CFRP shell reinforced with Carbon Aramid hybrid
fabrics in the pilot area, therefore capable of large energy absorption. The pilot
is seated in a semi-reclining position. The landing gear is retractable and
damped.
A C.G. release is fitted as standard, and an aerotow nose release can be fitted
on request.
1.2.2 Wing
The four-piece wing is cantilever and double trapezoidal. Removable wing
extensions are optional. It is constructed as a CFRP-Foam-Sandwich shell with
extruded spar caps of parallel carbon fibers and shear webs of reinforced
GFRP-Foam-Sandwich. Airbrakes are of the Schempp-Hirth type. Two integral
water ballast tanks carry a total volume of 194 liters (aprox. 42 UKgal, 51
USgal).
1.2.3 Horizontal Tail Unit
The horizontal tailplane has a stabilizer and elevators. Trimming is by means of
a spring on the control drive. The stabilizer is of GFRP-Foam-Sandwich
construction.
1.2.4 Vertical Tail Unit
The fin is similar to the stabilizer of GFRP-Foam-Sandwich Shell construction.
The rudder is of the CFRP construction.
1.2.5 Water ballast system
The water ballast system is controlled by a lever on the starboard side of the
cockpit. A Bowden cable connects the operating lever in the cockpit to a
torsional drive (in the fuselage center) which, on rigging the wing panels,
automatically hooks up to torque tubes actuating the ring tank dump valves.
These tubes are rotated to their "closed" position by spring force.
The operating lever in the cockpit runs over a half circle and the opening of the
valves can be locked in the each position from closed to fully opened positions.
The operating lever also drives the valve of the drainable tail ballast tank.
The tanks are located in the wings and have a total volume of 194l (aprox. 42
UKgal, 51 USgal). The ballast tanks are integral, each wing tank is divided into
2 sections located in lead space of the wings.