ABOUT FES

FES is a powerfull high-tech Front Electric propulsion System,

developed for high performance powered sailplanes. 

 

 

WHY CHOOSE FES ? 

 

 

 

 

Because it is FUN, EASY and SAFE!

WHY FRONT

- Front motor configuration is aerodinamicaly more clean compared to typical retractable configuration as there is no additional drag of a pylon, so lower power is required for equal performance.
- Lower power means smaller motor and smaller battery packs. Alltogether this means less additional weight, and lower costs.
- We figured out that in the nose of modern glider fuselage, is just enough space to fit small but very powerful custom designed brushless electric motor.
 

WHY ELECTRIC?

- Instant (RE)START - No warm up needed

- Much less noise - No loud exhaust noise

- Much Less vibrations

- Full torque from zero to max rpm (BLDC)

- No loss of motor performance at higher altitude

- CLEAN - No fuel pupmps, filters, spark plugs nor carburettor icing

- Low carbon footprint 

 

SELF-SUSTAINER OR SELF-LAUNCHER?

FES can be both: self-sustainer or self-launch system

 

FES AS SELF-SUSTAINER
 
Only 4-5kW of power is required for level fligth of typical FES equipped sailplane. With its maximum power at 22kW good climb rate to safe altitude is guaranted for any modern sailplane incuding two-seaters.

 

FES AS SELF-LAUNCHER

 

It is very nice combination with light 13,5m or 15m sailplanes. High landing gear is required to provide sufficient propeller clearence for safe self-launch, also from grass runway. 

FES is aerodynamically very clean, so 22kW is more than enough power to provide good climb rate for light sailplanes.

 

Recently we developed also more powerfull version of FES system, suitable to self-launch also heavier 18m sailplanes. With high landing gear also selflaunch from grass is not a problem without water ballast as demonstrated with new LAK17C FES.

WHICH NEW SAILPLANES CAN BE ORDERED WITH FES SYSTEM?

 

SCHEMPP-HIRTH, Germany - world leading manufacturer of sailplanes

Ventus-3 Sport FES, FAI 15-18m class, latest generation of Ventus. The ultimate choice for champions!

Discus-2cFES, 18m without flaps. Perfect choice for aeroclubs and recreational pilots. Certified by EASA in 2017.

 

 

DG Flugzeugbau, Germany - high performance sailplanes

DG-1001e neo, first double seater sailplane with FES system.

LS8-e neo, FAI Standard or 18m class racer.

 

 

SAirKo, Lithuania - high performance sailplanes

LAK-17B FES, latest generation of FAI 15-18-21m class sailplane, with MTOW 600 kg. EASA certified (2014).

MiniLAK FES, new generation of selflaunching FAI 13,5m class sailplane.

 

 

HPH Sailplanes, Czech Republic - high performance sailplanes

HpH Shark eS, FAI 18m class sailplane, with strong safety cockpit and many other features. EASA certified (2016).

 

 

Avionic, Poland - producer of famous Diana 2 FES

Diana 2 FES, FAI 15m racing class sailplane.

- Diana 3 FES, FAI 15m racing class sailplane.

 

 

Alisport Swiss, Switzerland - producer of UL self-launching sailplanes

Silent 2 Electro FES, FAI 13,5m class sailplane (Annex I), certified by DAeC!

 

 

Albastar, Slovenia - producer of UL self-launching sailplanes

AS 13,5 m FES and AS 15 m FES, FAI 13,5m class sailplane, and 15m recreational sailplane

 

 

 

 


 

IS IT POSSIBLE TO RETROFIT USED SAILPLANES REGISTERED IN EU WITH FES?

In principle, LZ design can not offer FES retrofit for used sailplanes. Unfortunately, EASA does not approve an "Experimental registration", like it is arranged in USA.

 

EXCEPTIONS

Exceptions are possible only for sailplanes that are Annex II types - these are by definitiony not EASA aircrafts and are therefore handled under national rules.

 

SPECIAL CASES

FES can be installed to used sailplanes in some special cases, where type certificate holders of specific glider type are involved. These are, for example:

- DG Flugzeugbau offers FES retrofit of some serial numbers of LS8 as published on this link. 

- Schempp-Hirth offers FES retrofit of used Ventus 2cxa.

 

For more information about FES retrofit please contact DG Flugzeugbau or Schempp-Hirth.

 

WHICH TYPES OF SAILPANES OUT OF EASA MIGHT BE SUITABLE FOR FES INSTALLATION?

Most of the sailplanes which were designed to fly with some kind of engine, can be also FES equipped!

 

The decision about possibility of FES retrofit is usually made on two main criteria:

 

1. MAXIMUM WEIGHT

The most important is the maximum weight of the non lifting parts (everything including pilot, except the wings). There must be enough reserve for additional 45kg of weight in the fuselage. If this requirement is not met, than it is not possible to install FES - due to safety reasons.

 

2. NOSE SECTION

Nose section should be as round as possible, slightly elliptic or eggy shape is also acceptable. We usually design a special spinner or adjust the front part of fuselage to be appropriate for FES installation.

 

 

AIRWORTHINESS

EASA REGULATION (European countries)

Airworthiness and certification can be done in different ways, depending on the "type" of sailplane:

- EASA used sailplane,

- EASA new sailplane,

- Annex II type sailplane (non EASA type of sailplane).

 

Certified EASA sailplanes require valid Certificate of Airworthiness (CoA).

If the sailplane is modified, CoA is not valid anymore.The following options are possible to make the saiplane airworthy again:

- Initially EASA Permit to fly (PtF) can be arranged based on EASA Approval of flight conditions. One of the conditions EASA requires to issue an Approval of flight conditions is that the application for certification project is applied to EASA by DOA or ADOA organization.

LZ design does not yet hold a DOA or ADOA certificate, so we cooperate with other companies, and sailplane manufacturers which are usually certified as ADOA.

 

CERTIFICATION

USED SAILPLANES

For countries under EASA regulations, Restricted Supplemental Type Certificate (RSTC) could be issued theoretically. Unfortunately EASA do not have yet available suitable procedures so that we could be actually able to arrange RSTC for different types of sailplanes (without cooperation of Type Certificate holder).

NEW SAILPLANES

Manufacturers of new sailplanes, which are also holders of Type Certificate (TC), can apply for a Restricted Type certificate (RTC) - FES system is then certified as a part of the sailplane.

ULTRA LIGHT, EXPERIMENTAL, HOME-BUILT SAILPLANES

Ultra light (UL), experimental or home-built sailplanes are excluded from EASA regulations as Annex II types. National Permit to fly can be issued, if accepted by local CAA. Certification is arranged according to local regulations, if it is required.

 

Please check EASA fees and charges in order to fully understand the costs involved in certification!

THE PRICE OF FES INSTALLATION

 The main factors influencing the total cost of FES installation, are:

  • single / double seater sailplane,
  • used as a pure sailplane / used, but prepared for FES installation in advance,
  • possible specific features of each sailplane type,
  • possible special local regulations and conditions,
  • required type of certification: EASA, Annex II type etc.

 

The manufacturers of the new aircrafts with built-in FES system, determine the final price of FES system themselves!

 

 

IS FES AVAILABLE AS A KIT?

FES is available as a KIT only for manufacturers, who have undergone a special training of FES installation. 

 

Installation of FES system (structural modifications of fuselage, mechanical and electrical installation) requires special tools and equipment as well as certain skills and experiences. Each type of saiplane has some specific features which requires the development od special parts and arrangementsFurthermore, to legaly fly your newly FES equipped sailplane, installation should be done by all the applicable regulations.

 

 

NEW DEVELOPMENTS

If you are developing a new model of powered sailplane and you are interested in FES - let us know! We will advise and help you make FES installation successful, easier and safer.

01

 

Turn on the FCU instrument.

 

Have FCU instrument always ON during the flight. Only a few moments is required from decision to start the engine to level flight or climbing.

02

Turn ON the "Power Switch".

The Power switch enables or disables a motor. To prevent unintentional enabling of motor, the Power switch is protected with red safety guard cover.

03

START - turn the throttle knob clockwise.

The knob with rotary encoder acts as a throttle and as a propeller brake. It is also used as a press button for functions like message confirmation, message recall etc.

04

STOP - turn the throttle knob counter-clockwise.

The endurance of a FES system with a full charge and operating in level cruise (requires 4-5 kW of power) is approximately one hour (for sustainer).

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