Made with passion
for flight

LAK-17B FES

The LAK-17B FES experience summary

LAK-17B is new version of LAK17A. Regarding A version, B has new wings with modified geometry and new wing profile, which allow even higher wing loadings than competitors. Fuselage and tail section is identical like A version.

The creators of Front Electric Sustainer ( FES ) are Luka Znidarsic and Matija Znidarsic, both experienced sailplane pilots and mechanical engineers in Slovenia.

Front refers to the motor’s location, right in the nose of the sailplane. A 1 meter carbon fibre propeller automatically extends when the outrunner is operating. When not in use, the propeller blades fold against the nose of the sailplane thus reducing drag. Each blade weighs just 240 g.

The Znidarsic’s developed their own brushless DC synchronous permanent magnet electric motor and controller for the application which is light, small, and mounted on top of the main wheel box. The motor is 7.3 kg (16.1 pounds) and puts out 22 kW (30 horsepower) at 116 Volts.

 The total weight for the power package is 45-50 kg (99-110 pounds), with Kokam lithium-ion batteries in two packs (each behind the rear spar, balancing the weight of the motor and propeller in the nose).

If batteries are discharged during flight using the motor, they are easily accessible from the top of the fuselage so that you can take them out for charging. Unlike lead-acid batteries, Li-Po batteries can be stored for 3 or 5 months without significantly losing charge. Charging time of batteries is about 6 hours (2 hours with a quick charger).

For more information about FES please visit www.front-electric-sustainer.com

Technical data

  • WEIGHTS
  • DIMENSIONS
  • PERFORMANCE DATA
  • ENGINE
  • COCKPIT
  • OPTIONS
15 M
18 M
21 M
Empty Weight, kg
305
320
332
MTOW, kg
550
600
600
Water Ballast in Wings, kg
180
200
200
Min Wing Loading, kg/m²
40.8
37.8
34.7
Max Wing Loading, kg/m²
60
58
51.8
15 M
18 M
21 M
Wing Area, m²
9.18
10.32
11.58
Fuselage Length, m
6.53
6.53
6.53
Fuselage Height, m
1.32
1.32
1.32
15 M
18 M
21 M
V_ne, km/h
275
275
220
G Limits Without Ballast
-2.65/+5.3
-2.65/+5.3
-2.65/+5.3
15 M
18 M
21 M
Type
FES-LAK-M100
FES-LAK-M100
FES-LAK-M100
Overall System Weight, kg
52
52
52
Batteries Weight, kg
32
32
32
Total Energy Capacity of the Batteries, kWh
4.2
4.2
4.2
Single Battery Charging Time
4
4
4
Continuous Power, kW
20
20
20
Max Power, kW
22
22
22
Propeller Diameter, m
1.0
1.0
1.0

01.

Instrument panel

Choose your instrument panel from these standard layouts. Custom layouts are possible under request.

02.

Adjustable pedals

Pedals adjustable in flight to change position of legs and body during long flights.

03.

Adjustable seat

Seat-back adjustable in flight allows changes in one’s position during long flights.

04.

Leather handles

Leather-covered handles feel cool in your hands

  • Landing gear position warning when opening the airbrakes
  • Shock absorbing air cushion
  • Air inflatable back support pillow, in-flight adjustable to desirable spine position. Strongly recommended to improve sports results
  • Antenna for a transponder preinstalled in the fin
  • Factory installed ELT
  • Holes in the fin water ballast tank protects from overfilling the tank and CofG moving behinf the limits
  • LED strobe, low energy consumption
  • Factory installed oxygen system
  • Tinted canopy glass
  • Air extractor
  • Microphone in the instrument panel
  • Choise of cushion materials, fitting the LAK standard shape or a customised shape
  • Sockets for a headset
  • Installation of a CD or USB player
  • Bluetooth devices