Foto: Jakub Nanowski - EPGD Spotters

Take off when you want.

No longer wait for a tow-plane if you have one the powerful retractable Solo engine installed. Once you have retracted the engine after taking off, the low extra weight of the engine unit and its optimized integration will make you forget that you're flying a self-launching sailplane.

The engine is rigidly coupled with the pivoting propeller tower and gets swiveled with it when the propeller gets extracted, so both engine and exhaust system remain in the engine box. The modern ILEC control unit allows automated operation, avoids operational errors and makes engine use a pleasure.

Fault Tolerance by Redundancy.

In order to assure a save mode of operation, a redundancy system has been developed, which can be manually activated if the normal engine control fails, e.g. due to a faulty sensor. It consists of a simple ECU, which contains a characteristic diagram. This diagram (fuel supply over engine speed) controls two additional injection valves. The fuel is guided through two hoses into the manifolds. The engine speed and the fixed ignition timing are detected by an additional inductive sensor. The ECU has two ignition controllers which control the two ignition coils, which are also used for the normal engine operation. 

The redundancy system has no correction for air pressure and temperature. The engine operational data and limitations are unchanged if the engine is operated using this system. 

Simple to Engage.

Engine start-up is straightforward and easy thanks to the newly designed automatic. To engage the engine, the pilot only needs to switch on the ignition and press the start button once the engine has been fully extracted. The engine’s start setup is always optimized by a microprocessor to match the current environment. 

Simple to Stop.

Disengaging the engine is just as easy. After switching off the ignition on the Ilec engine control unit, the control unit automatically stops and fixes propeller in the correct upright position and the engine gets retracted.  

The Engines.

SOLO has specifically designed the two-stroke engines of our self-launching models for retractable engine systems. The Ventus-2cxM uses the single-carburator engine SOLO 2625-01 with a performance of 52 hp (38 kW), while the Arcus M and Quintus M are equipped with the stronger injection engine SOLO 2625-02i with electronic double ignition and a performance of 68 hp (50 kW).

Both engines are characterized by low weight, compact measurements, double-ignition, high reliability and a long life-time. 

Gallery

Engine Specifications

  • Twin-cylinder in line
  • Two-stroke engine 
  • Liquid cooling 
  • Lubrication by fuel-oil-mixture 
  • One diaphragm carburetor
  • Dual electronic high-voltage ignition 
  • Crankshaft layout for belt transmission 
  • Electric starter 
  • AC generator
Engine displacement 625 ccm
Compression rartio 9.5 : 1
Ignition unit Dual electronic high-voltage ignition (Ducati Energia) or ISKRA
Ignition plugs BOSCH W5 AC, Gap at electrodes 0.5 mm
Carburetor MIKUNI diaphragm carburetor Typ BN 38
Direction of rotation Clockwise, seen in direction of flight
Fuel 2-Stroke-mixture, AVGAS 100LL, premium gas min. 95 ROZ
Mixture Mixture ratio 1:50, 2-stroke Castrol mineral oil or synthetic oil, or other oils with specification according to JASO FC or FD
Dry weight 23 kg
Generator 12 V / 150 W
Coolant Engine coolant (Glysantin BASF G48), tab water (0-20° dh) in a mixture of 40:60 (27 °C)
Take-off-speed, -power 6250 rpm with a power of 39 kW (53 hp)
Max. cont. speed, -power 6250 rpm with a power of 39 kW (53 hp)
Max. rpm 7000 rpm
Idle rpm approx. 2300 rpm
Max. temp. cooling liquid 115 °C (240 °F) measured in the cylinder head
Fuel consumption Max. continous power 5.94 US gal./hr. (22.5 l/h)
  • Twin-cylinder in line
  • Two-stroke engine
  • Liquid cooling
  • Lubrication by fuel-oil-mixture
  • Electronic fuel injection
  • Dual electronic high-voltage ignition
  • Redundancy system
  • Crankshaft layout for belt transmission
  • Electric starter
  • AC generator
Engine displacement 625 ccm
Compression rartio 9.5 : 1
Ignition unit Dual electronic high-voltage ignition, mapped
Ignition plugs BOSCH W5 AC, Gap at electrodes 0.5 mm
Fuel injection Electronic, two butterfly shutters, mapped
Direction of rotation Clockwise, seen in direction of flight
Fuel 2-Stroke-mixture, AVGAS 100LL, premium gas min. 95 ROZ
Mixture Mixture ratio 1:50, 2-stroke Castrol mineral oil or synthetic oil, or other oils with specification according to JASO FC or FD
Dry weight 24 kg without exhaust (according to airframe manufacturer)
Generator 12 V / 500 W
Coolant Engine coolant (Glysantin BASF G48), tab water (0-20° dh) in a mixture of 40:60 (27 °C)
Take-off-speed, -power 6600 rpm at a power of 50 kW (68 hp)
Max. cont. speed, -power 6600 rpm at a power of 50 kW (68 hp)
Max. rpm 6700 rpm
Cut off speed by CPU 6700 rpm
Idle rpm approx. 2300 rpm
Max. temp. cooling liquid 115 °C (240 °F) measured in the cylinder head
Fuel consumption Max. continous power 6.47 US gal./hr. (24.5 l/h)

Self-launching sailplanes with two-stroke-engine:


Even though designed for self-launch capabilities without compromises, the Arcus is still an extremely agile two-seater with very balanced flight characteristics. The motorglider’s performance spectrum reaches from ambitious cross-country flights to unbelievable record flights and regularly puts the self-launching Arcus into top positions in competitions and championships. 


If you are a sporty pilot and you are looking for a self-launching glider that is handy and agile, has a sophisticated and proven engine system that you can hardly notice when gliding, there are few alternatives to the Ventus-2cxM in its class. The automated engine control ensure safe handling and foolproof operation, but does not take control and influence out of the pilots hands.


The handy 23m wingspan makes maneuvering on the ground easy, and even more so once in the air. A very slim wing with high aspect ratio and up to 250 liters of water ballast ensure wing loads between 39 and 59 kg/m² make this glider extremely flexible, further enhanced by the independence provided by the powerful and easy to operate engine system that allows the Quintus to take-off wherever needed.

The handiness of the 23m wingspan makes for easy maneuvering on the ground, but especially in the air.