Stemme S12

S12 Twin Voyager
Stemme S12 AERO 2016
Stemme S12 at AERO 2016
Role Motor glider
National origin Germany
Manufacturer Stemme
First flight April 2015
Introduction April 2015
Status Under development (2015)
In production (2017)[1]
Number built >30[2]
Developed from Stemme S10

The Stemme S12 is a German high-wing, two-seat motor glider produced by Stemme of Strausberg. It was introduced at AERO Friedrichshafen in April 2015, shortly after its first flight.[3]

Design and development

Based in the Stemme S10, the Stemme S12 features a cantilever wing, a T-tail, a two-seats-in-side-by-side configuration enclosed cockpit under a bubble canopy and a single engine with a retractable propeller.[3]

The aircraft is made from composite material. Its 25 m (82.0 ft) span wing employs winglets. The mid-fuselage-mounted engine is the 115 hp (86 kW) Rotax 914 F2/S1 four-stroke turbocharged powerplant driving a retractable, folding, variable-pitch propeller. Its maximum glide ratio is 53:1.[3]

The $8 million Dzyne Unmanned Long-Endurance Tactical Reconnaissance Aircraft (ULTRA) is an uncrewed derivative deployed as part of an affordable ultra-long endurance ISR demonstration, capable of flights up to 80 hours.[4]

Specifications (S12)

Data from Grady[3]

General characteristics

  • Crew: one
  • Capacity: one passenger
  • Length: 8.42 m (27 ft 7 in) (propeller retracted)
  • Wingspan: 25.0 m (82 ft 0 in) - 11.4 m (37.4 ft) span when folded
  • Height: 1.75 m (5 ft 9 in)
  • Wing area: 19.95 m2 (214.7 sq ft)
  • Aspect ratio: 31.33
  • Gross weight: 900 kg (1,984 lb) MTOW
  • Fuel capacity: 120 litres (26 imp gal; 32 US gal)
  • Powerplant: 1 × Rotax 914 F2/S1 four cylinder, liquid and air-cooled, turbocharged, four stroke aircraft engine, 86 kW (115 hp)
  • Propellers: two-bladed retractable, folding, variable-pitch propeller

Performance

  • Maximum speed: 259 km/h (161 mph, 140 kn) at 10,000 feet MSL
  • Cruise speed: 230 km/h (140 mph, 120 kn)
  • Range: 1,759 km (1,093 mi, 950 nmi)
  • Endurance: 9.2 hr @ 55% power
  • Maximum glide ratio: 53:1
  • Rate of climb: 4.21 m/s (829 ft/min)
  • Wing loading: 45.11 kg/m2 (9.24 lb/sq ft) at MTOW

See also

References

  1. ^ Photos: U.S. Sport Aviation Expo 2017 (27 January 2017) Flying
  2. ^ "Aircraft Inquiry".
  3. ^ a b c d Grady, Mary (15 April 2015). "Stemme Debuts S12 Motorglider At Aero". AVweb. Retrieved 20 April 2015.
  4. ^ Steve Trimble (9 May 2024). "U.S. Air Force Confirms ULTRA Deployment In Middle East". Aviation Week.