Specs
STEMME S10-VT Technical Data
The high-performance motorglider
The propeller blades extend into the airstream automatically by centrifugal force when the engine is started.
| Dimensions, External | |
| Wing span | 23.00 m (75 ft 5½ in) |
| Wing aspect ratio | 29.29 |
| Width, wings folded | 11.40 m (37 ft 4½ in) |
| Length over-all | 8.42 m (27 ft 7½ in) |
| Fuselage max width | 1.18 m (3 ft 10½ in) |
| Height over-all | 1.80 m (5 ft 10½ in) |
| Wheel track | 1.15 m (3 ft 9¼ in) |
| Wheel base | 5.42 m (17 ft 9½ in) |
| Propeller diameter | 1.63 m (5 ft 4¼ in) |
Dimensions, Internal |
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| Cockpit width | 1.16 m (3 ft 9½ in) |
| Cockpit height | 0.93 m (3 ft ½ in) |
| Areas |
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| Wings, gross | 18.70 m2 (201.3 sq ft) |
| Horizontal tail, gross | 1.46 m2 (15.8 sq ft) |
| Vertical tail, gross | 1.51 m2 (16.3 sq ft) |
| Weights and Loadings |
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| Weight empty: | 660 kg (1,455 lb) |
| Max. take-off and landing weight: | 850 kg (1,874 lb) |
| Max. wing loading: | 45.5 kg/m2 (9.31 lb/sq ft) |
| Max. power loading: | 10.06 kg/kW (16.53 lb/hp) |
| Performance, general |
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| Never-exceed speed (VNE): | 146 kt (270 km/h; 168 mph) |
| Manoeuvring speed: | 97 kt (180 km/h; 112 mph) |
| Stalling speed (flaps in landing position): | 42 kt (78 km/h; 48 mph) |
| g-limits: | +5.3/-2.65 |
| Performance, powered |
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| Max. cruising speed at MSL: | 121 kt (225 km/h; 139 mph) |
| Max. cruising speed at FL100: | 140 kt (248 km/h; 154 mph) |
| Max rate of climb at S/L and MTOW: | 4.14 m/s (817 ft/min) |
| Service ceiling: | 30,000 ft (9,140 m) |
| T/O-run (MSL, ISA, MTOW): | 205 m (675 ft) |
| T/O-distance (MSL, ISA, MTOW): | 447 m (1470 ft) |
| Max range with standard fuel (2×45 ltr): | 697 nm (1,290 km) |
| Max range with extended fuel (2×60 ltr): | 929 nm (1,720 km) |
| Performance, unpowered | |
| Best glide ratio at 57 kt (106 km/h; 66 mph) | Up to 50 |
| Min rate of sink at 45 kt (83 km/h; 52 mph) | Down to 112 ft/min (0.57 m/s) |
| Operational Noise Levels |
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| To German light aircraft rules LSL, chapter X | 71.3 dBA |
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Independence … The HandlingThe engine and the twin-undercarriage provide a maximum operational independence while taxiing and flying. As a sailplane pilot you will never need a person to run your wing. While the S 10-VT can be easily flown cross country and under power, we have also considered your independence during ground transportation. An ingenious trailer is available which permits a “One-and-a-half-person” to stow or rig the plane. Between flights you can store the S 10-VT in a normal size T-Hangar since a single person can fold the wings in less than five minutes to a span of 11.2 m (37 ft). (Option: wing-folding system) |
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Comfort … The CockpitApart from ideal soaring and power flight performance, the S 10-VT ensures the ultimate pleasure of flying in unparalleled comfort. The S 10-VT’s side-by-side is an ideal environment for social, competition or instructional flying. The ergonomically designed cockpit provides the pilot unmatched comfort on even the longest flights. Easily adjusted rudder pedals and six point adjustment of the seats match the needs of short and special seats for very tall pilots are available. Ambient temperature is controlled by an ample supply of fresh air through an adjustable air distribution system. A solar-panel (Option) ensures power-supply for the gliding instrumentation during longer soaring periods. |
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Safety … 5-SEC-RESTARTTo restart the engine the nose cone is pushed forward and this also opens the cooling vents. The Propeller-blades only unfold into the air-stream when the engine is started. Therefor, the S 10-VT suffers neglible drag or trim change during the restart period, and it can perform a normal glider circuit and landing if the engine fails to start. This is much safer than the situation of a fold-out-engine motorglider which fails to start – becoming extremely dangerous very quickly. The superb handling of the S 10-VT, both on the ground (aided by the twin undercarriage) and in the air – even at the stall, makes the S 10-VT easy and safe to operate. FuselageA central steel tube framework serves as the mounting for the wings, undercarriage and fixed engine, and gives an unobstructed access for engine servicing. All control linkages and connections for the wings are located above the horizontal firewall seperating them from the engine compartment. The rear fuselage (which is a carbon fibre construction) is bolted to this central framework. The cockpit is a carbon fibre shell, kevlar-lined for impact safety. Inside width is 1.16 meters and the one piece canopy hinges from the front with supporting gas springs. The seat-backs have 6 mounting positions, and can be adjusted to the proper seating-position. The “T”-tail has a dampened elevator, and the rudder size is ample for good control coordination. UndercarriageThe electrically retractable undercarriage is well sprung. Its two 5 inch wheels with a track of 1.15 meters are fitted with disc brakes. There is a manual override system to lower the gear in the event of electrical failure. The tailwheel is steerable with the rudder. Optional wide-tired landing gear is available (using 2 6 inch wheels) for shorter take-off runs on soft grass fields. |
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PropellerThe STEMME-patented propeller consists of a central-mounting and two jointed blades. In gliding configuration the blades are folded into the contour of the fuselage and are covered by the movable nose cone to leave an aerodynamically clean fuselage. Start-up readiness is achieved by simply putting the nose cone forward via its lever with no perceptible change in trimp or drag. Therefor a critical situation at low altitude does not emerge from a sudden reduction in gliding performance. The propeller blades extend into the airstream automatically by centrifugal force only when the engine is started. When the engine has been stopped and the prop has come to a rest, the blades fold inwards automatically by spring loading. Once the blades are aligned and the nose cone is retracted it encloses the propeller completely to leave a clean aerodynamic fuselage. A variable pitch propeller with two positions for take-off and cruise improves significantly the take-off runs and cruising performance. EngineAir cooling is achieved by air inlet and outlet ducts which are opened by the extension of the nose cone. The powerful S 10-VT engine, the turbo-charged Rotax 914, produces 85.7kW (115HP). The engine is equipped with watercooled cylinderheads, automatic adjustment by hydraulic valve tappet, optional intercooler and integrated reduction geari=2.43. Additionally the electronic dual ignition offers increased safety. Wings |
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The wings are completely new developed. This has given the opportunity to incorporate the very latest technology and aerodynamics, achieving significant benefits in handling and performance – confirmed by many satisfied owners.
The wings are made of carbon fibre constructions in three sections. A 45 liter fuel tank, and Schempp-Hirth air-brakes are isntalled in both ends of the central section of the wing. Optional 60 liter fuel tanks are available. The optional, removable winglets improve the excellent flight characteristics and are reducing the sink rate in circular flight without imparing the spectacular gliding performance in fast, straight flight. |
The Philosophy
Uncompromised performance, independence, safety and convenience – is the philosophy behind the high-performance S 10-VT motorglider. Independence and the immeasurable feeling of freedom make soaring the high art of sport aviation. The S 10-VT is equipped with a powerful aircraft engine and aerodynamically clean fuselage to assure a maximum level of safety. Features such as the retractable twin undercarriage and the revolutionary propulsion system put the S 10-VT in a class of its own. As a side-by-side 2 seater, the S 10-VT enables you to share the joy of gliding with a friend while enjoying every comfort. The S 10-VT embodies the perfection every member of the STEMME team has worked for. It uniquely combines the qualities of a high-performance sailplane and a comfortable power plane without compromises.This was proven not at least with the sensational flight of Klaus Ohlmann in the Andes: 2463 km of pure gliding in 14 hours in Dec. 2000 with a STEMME S 10-VT.
The huge wingspan of 23 meters in combination with the high performance HQ41 wing section and the “clean” fuselage, offer a glide ratio potential of 50:1 and a minimum inherent sink rate of only 0.56 m/s (112 ft/min). This performance makes the STEMME S 10-VT one of the very best performing sailplanes ever built. The S 10-VT is the easiest to handle and most good-natured open class sailplane. The new design of the flap/aileron interaction leads to a high degree of maneuverability in slow flight. And 18.7m² of wing area enables the S 10-VT to exploit poor thermals with ease.
The state-of-the-art HQ laminar profile is a special developedment for the wings of the S 10-VT to achieve an outstanding soaring performance. It was designed by the distinguished experts on airfoil profiles, Horstmann and Quast at the Aerodynamic Design of the DLR Braunschweig, Germany. The use of artificial turbulators underneath this profile prevent formation of the drag inducing laminar separation bubble. Accumulation of bugs or rain on the wings will have very little effect on gliding performance.
The unique propulsion system and the twin-undercarriage offers a fully fledged power plane which enables taxiing, take-off and landing without outside help. You can take full advantage of this independence to spend your precious time soaring – not waiting for other people and ground procedures. The S 10-VT takes you to the thermals very quickly – high cruising speeds put even distant soaring opportunities within easy reach and will get you home again after a day’s soaring. The highly reliable “5-Sec-Restart” gives you safety when soaring cross-country. With negligible drag or trim change even low height restarts are easy – and should the engine fail to start, a normal glider circuit and field landing can be performed.
