trust in our proven experience. be innovative.

The idea of electric motorgliding

The elfin e-powered motorglider continues the success story of the still unbeaten high-performance motorglider STEMME S10 which had its maiden flight more than 30 years ago. The STEMME S10 has been developed and is built by STEMME AG in Strausberg/Berlin. The plane has been designed and constructed by Dr. Reiner Stemme and his team during his time as manager and CEO of STEMME AG and was for the first time certified in 1990 by the LBA (German Luftfahrtbundesamt).

A highlight in its history was the successful mission »On Top of the World« in the Himalaya region using an underwing 3D camera system from DLR. We have the ambitious objective to continue this story in a new generation of planes; therein we rely on radical innovations. We cooperate with German research institutes and the industry - so we can best incorporate today’s knowledge in this project.

The elfin design ist a complete new development and does not base upon the existing S10. GmbH, the present company of Dr. Reiner Stemme, is not connected to STEMME AG.

Fly the new Reiner Stemme Class – side-by-side with e-power independent and safely

  • Side by side cockpit in front of wing with panoramic view and low sill for easy entry

  • retractable propeller system

  • directly coupled electric motor in fuselage nose

  • main battery in rear compartment for best mass balance

  • auxiliary battery behind cockpit at CG

  • specific wing airfoil 20e-143 without premature lift plateau, seamlessly optimized over the entire wing span

  • ambitious wing-to-fuselage-intersection design with fillets for drag reduction

  • turbulent root section airfoil and root twist

  • outer wings foldable to 36.25 ft (11.05 m) wingspan for taxiing and hangaring

  • inner wing lengthwise pivoting over fuselage for 9 m by 2 m (30 x 6.5 sqft) overall footprint

  • enhanced safety through full ballistic parachute recovery system

  • certification EASA CS-22 and FAA equivalent. 

elfin specification sheet





Wing span

65.6 ft

20 m

Wing area

266 sqft

16.2 m²

Wing aspect ratio



Length overall

28.5 f

8.7 m

Height over tail plane

5.6 ft

1.7 m

Wheel track

3.9 ft

1.2 m

Wheel base     

18 ft

5.5 m

Cockpit width

4.1 ft

1.25 m

Cockpit height

3.2 ft

0.98 m

Cockpit entry sill height

2.82 ft

0.96 m


Operating empty weight

1,190 lbs

540 kg


1,984 lbs

900 kg

MTOW without water ballast

1,808 lbs

820 kg

Wing loading (min–max)

7.8–11.3 lbs/sqft

38–55.5 kg/m²

Max. cockpit loading

441 lbs

200 kg


Glide ratio

1 : 50 class

1 : 50 class


Never-exceed speed VNE

151 kts

280 km/h

Manoeuvring speed VA

108 kts

200 km/h

Stalling speed

42 kts

78 km/h

Range (elfin 20.e)

T-O to 1.640 ft
+ > 1h powered flight

T-O to 500 m
+ > 1h powered flight


Range (elfin 20.ex)

540 nm

1.000 km

Cruise (elfin 20.ex) @ FL100

116 kTAS

215 km/h