a pylon behind the cockpit to extend a propeller. 11 different types, from 7 manufacturers, such as the Alisport Silent 2 Electro, use the front electric sustainer (FES) system with a folding propeller in the nose. Advantages of electric power over gasoline include: Faster and more reliable transition from gliding to powered flight, as the time and risk required to start and warm up an internal combustion engine is eliminated. For example, the Antares 20E transitions from gliding to powered flight in under 12 seconds. With a FES system maximum power can be available in 1–2 seconds. For types that use a pylon, lower drag and sink rate are achieved with the pylon extended and the motor not running, as there is no radiator as required to cool a gasoline engine. For FES systems, the drag from the folded propeller in the nose is negligible if the engine does not start. For safe operation, the "Engine out and not running" performance is used to plan in-air restarts in the event of a problem (even for electrics). The reduced sink-rate of electric-powered motor-gliders "engine out and not running" allows a lower altitude for a safe in-air restart. For types that use a pylon, belt reduction drive and associated reliability issues are eliminated. As an electric motor can turn at a lower RPM than typical gasoline engines, it can be mounted at the top of the mast without a reduction system, eliminating belt-drive issues. Greatly reduced noise, allowing take-off from locations where other powered aircraft are not permitted. Disadvantages of current electric powered motor-gliders as compared to gasoline include: Reduced range or climb altitude, as the energy stored per unit weight for available batteries is less than gasoline. Gliders with pylon-mounted electric motors are slightly heavier than those with gasoline engines due to the batteries. An FES system weighs about the same as a two-stroke engine. Increased cost. While electric motors are comparably inexpensive, low-weight batteries suitable for motor-gliders are a little more expensive than gasoline engines. Electric sustainer systems (with power to sustain flight but not self-launch) are optional for the Schempp-Hirth Ventus-3, HPH Shark and ESAG LAK-17B. These three all use the FES as used for self-launching lighter gliders, such as the Alisport Silent 2. Jet The first production self-launching motor glider fitted with a jet engine was the Caproni Vizzola Calif. The jet engine was mounted inside the fuselage