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DEVELOPMENT and DESCRIPTION
The Standard Cirrus, designed by Dipl. Ing. Klaus Holighaus, flew
for the first time in March 1969. It is a high performance 15 metre version of the Open Cirrus, but has nothing in common with it in
appearance. It has a new fuselage with a T-tail and a roomy cockpit complete with a one-piece hinged canopy. The wing has a new Wortmann
aerofoil but, like the Open Cirrus, no flaps, and the aspect ratio is reduced from 25 to 22.5, providing a good climb rate even with heavy
pilots.
The prototype Standard Cirrus first flew in March 1969 and
production began in the summer of that year. The type proved to have
very docile and pleasant handling qualities and soon made its mark in
competition flying, winning the Standard Class at the International
Soaring Competition at Hahnweide in 1969 and going on to win many
national gliding contests. By April 1977, when production by
Schempp-Hirth ended, a total of 700 Standard Cirruses had been built,
including 200 built under licence by Grob Flugzeugbau, makers of the
Astir series of sailplanes, between 1972 and July 1975. Manufacture of
the type is being continued under licence from Schempp-Hirth by the
French firm Lanaverre Industrie, formed at Bordeaux in 1977 by Morin SA
and the boatbuilding concern Yachting France; 30 had been completed by
1 January 1979 as the Lanaverre Standard Cirrus, also known as the SCAP Cirrus 78L. VTC of Yugoslavia had also built 14 Standard Cirrus 75-VTCs
by early 1979.
The Standard Cirrus 75 was an improved variant produced by
Schempp-Hirth in 1975 which had enlarged fairings at the wing roots,
increased area air brakes, a modified nose similar to that of the
Nimbus 2, jettison valves for the wing water ballast tanks repositioned
to behind the monowheel, and a new type of easy-to-rig tailplane
fitting. The cantilever mid wings and the ailerons are glassfibre/foam
sandwich structures. The large glassfibre Schempp-Hirth airbrakes
operate only on the upper surface of the wings, reducing the risk of
damage when landing away and keeping the lower surface of the wing
aerodynamically clean. The fuselage is a glassfibre shell, 1.5mm thick,
stiffened with bonded-in foam rings, and the T-tail unit is of
glassfibre/foam sandwich, the tailplane being an all-moving surface.
The standard landing gear is a manually-retractable monowheel, but a
non-retractable faired mono-wheel is optional for the customer; in both
cases there is a drum brake. The pilot sits in a semi-reclining seat
and has adjustable rudder pedals.
The Standard Cirrus has exceptionally docile and pleasant
handling characteristics and has won national competitions all over the
world.
PERFORMANCE DATA
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Span
|
15 m |
| Length |
6.35m |
| Height |
1.32 m |
| Wing Area |
10.0m² |
| Wing Section |
Wortmann FX S-02-196 mod. |
| Aspect Ratio |
22.5 |
| Empty Glider Mass |
215kg
|
| All-Up Mass |
390kg |
| Water Ballast |
80kg |
| Maximum L/D |
38.5 at 48.5 kt |
| Stalling Speed |
33.5kt |
Minimum Sinking Speed
|
0.6m/s |
| Max. Rough Air Speed |
119km/h |
| Never Exceed Speed |
119km/h
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Three Axis View Schempp-Hirth Cirrus
GGC's STANDARD CIRRUS – VH-GVE
The Cirrus was purchased new through Bacchus Marsh Aviation Services
in July, 1975. Assembled at the factory it was finished by the local
agent. Being an early “75” variant it was fitted with a prototype water
dump valve which proved unsatisfactory and since been replaced.
VH-GVE is the current Australian record holder for speed around
a 300km triangle of 143.32km/hr, the record being set by Terry Cubley
in December 1980 out of Mildura. Suffering originally with
problems of gelcoat cracking it has been subsequently refinished. It
has been modified by the installation of a nose release to improve its
aerotow launching characteristics.
For many years the best performing standard class glider in the
club fleet it has now been eclipsed by more recent acquisitions, but is
still regarded by many as the most responsive, though unforgiving, of
the club fleet.
Cirrus GVE was sold to Beverley Soaring Society in September 2006.
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