ZK-FOS

ZK-FOS is a Stemme S10-VT, a single-engine piston aircraft. SkyMeter has tracked 90 flights totalling 34 hours of airtime via ADS-B. The most frequent segment is NZNV to NZNV. Service window in our records spans 432 days. The Stemme S10-VT has a maximum takeoff weight of 1,874 lb, light wake category.

About the Stemme S10-VT

The Stemme S10 is a high-performance motor glider built by Germany's Stemme GmbH, combining the soaring efficiency of a sailplane with the self-launch capability of a powered aircraft. First flown in 1986, the S10 pioneered the use of a retractable propeller and turbocharged Rotax engine mounted behind the cockpit, driving a folding two-blade prop that tucks flush into the fuselage for pure gliding flight. With a wingspan of 23 meters and a glide ratio exceeding 50:1, the S10 can climb under power to altitude, shut down the engine mid-flight, and soar for hours on thermals or ridge lift, then restart aloft and motor home.

This dual capability made it popular for cross-country soaring, aerial survey, and pilot training in Europe. The S10-VT variant added a turbocharged Rotax 914 engine for better high-altitude performance and a slightly refined cockpit. Stemme later developed the S12 and S15 with even longer wings and composite refinements, but the S10 remains the most widely recognized model.

Its unique retractable propulsion system and exceptional L/D ratio set it apart from conventional light aircraft and pure gliders alike. SkyMeter has tracked flights across airframes and operators, with distinct routes observed.