Planeur-Lak

 

 

 

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The LAK-17 MINI is a new generation FAI 13,5 m class sailplane. LAK-17 MINI is made of hybrid composite materials such as kevlar, carbon, glass fibre. The wing spar is made of modern carbon rods GRAPHLITE SM315 and has a double T section. The weight of each wing panel is 40 kg. The airbrake are situated in upper surfaces only.

The retractable landing gear has a 350×15 mm tire and shock absorber. The hydraulic main wheel brake is actuated by an air brake handle. The rudder pedals are adjustable in flight. All controls, hook up automatically. The wings incorporate fork – type spar roots joined with two pins. The elevator hooks up automatically during assembly.

The cockpit is of monocoque construction. The manually controlled seat pan and an adjustable seat back together with optimally arranged control elements offer notable comfort on long flights. The one piece Weiss canopy hinges forward. On the left side there is a sliding window with ventilation scoop. The instrument panel lifts up together with the canopy.

Sailplane could be produced in three versions:

  • LAK-17 MINI – pure glider with fuselage ballast tank jettisonable in flight;
  • LAK-17 MINI T – this motorglider is with retractable selflaunching system with Solo 2350 engine.
  • LAK-17 MINI FES – motorglider Front Electric selflauncher is a highly effective propulsion system with a light but powerful brushless electrical motor and small and foldable propeller at the front part of fuselage.

The brochure for the MINI LAK can be found here.

 

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 main whell box. The motor is 7.3 kg (16.1 pounds), and puts out 22 kW (30 horsepower) at 116 Volts. 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 quick charger) .

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

 


The LAK – 19 is a standard class sailplane designed and certified to the JAR – 22 category “U” specifications. It is a midwing glider without flaps, T – tail, retractable main landing gear with the shock absorber, pneumatic tail wheel and is capable of carrying 180ltr water ballast.

LAK-19 sailplane is made of hybrid composite materials such as kevlar, carbon, glass fibre. The wing spar is made of modern carbon rods GRAPHLITE SM315 and has a double T section. The weight of each wing panel is about 55 kg. The airbrakes are situated in upper surfaces only. The wing airfoil is LAP 92 – 130/15 and it passes into the LAP 92 – 150/15 in the tip.

The cockpit construction is monocoque . The manually contoured seat pan and an adjustable seat back together with optimally arranged control elements offer notable comfort on long flights. The one piece Mecaplex canopy hinges forward. On the left side there is a sliding window with ventilation scoop. The instrument panel lifts up together with the canopy.

The retractable landing gear has a 350×15 mm tire and shock absorber. The mechanical main wheel brake is actuated by a handle on the control stick. The rudder pedals are adjustable in flight. All controls, including the water ballast system, hook up automatically. The tow release is mounted near the main landing gear and permits winch as well as aerotow take off. The wings incorporate fork – type spar roots joined with two pins.

The T-tail (fixed stabilizer with elevator) provides stable and responsive pitch characteristics. The elevator hooks up automatically during assembly. The glider is fitted with a fin ballast tank (capacity 7ltr) in order to compensate the nose-heavy moment created by the high ballast loads in the wings tanks. The fin ballast tank is jettisonable in flight. The water ballast is filled in, and emptied out through the holes at the bottom of the wings. The VHF antenna is mounted in the vertical fin.

Warranty 24 months or 200 flight hours whatever comes first.