At the Aero Trade Fair 2001 at Friedrichshafen, the Silence was displayed in a corner of one of the halls not for sale purposes but simply to show how modern materials could be constructed in a homebuilder's workshop. The great public interest shown in this design finally persuaded the team to continue optimising it towards serial and kit production, and to found a manufacturing firm. On September 4, 2002, the first Silence of the serial production version took off for its maiden flight, this time powered by the Mid-West AE 50 Harrier 50hp rotary engine, which weighed 77lb less than the engine used in the prototype. The Harrier engine is JAR-22 certified and also powers the Schleicher retractable engined motorgliders.

The fact that the shape of the Silence is so reminiscent of the famous Spitfire is for good aerodynamic reasons the simple, elliptical wing offers nearly optimum lift distribution, the smoothly rounded fuselage promises low drag and, at the same time, the whole thing looks attractive! The main building material Nomex (aramide fibre) honeycomb plates, sandwich-covered with GRP has not often been used in light aviation. Though not particularly cheap, this material does have some clear advantages. It is possible to build strong, stiff components, uniting high surface quality and strength with low weight. The use of glass fibre as a covering sandwich layer results not only in good protection against damage, but makes the aircraft easy to construct, simple to repair and straightforward to inspect for damage. Additionally, this material absorbs a great deal of energy in case of a crash. For high load-carrying internal structures, such as the wing spars or engine carrier, carbon fibre rovings are used, well protected against exterior damage. The highly energy-absorbent aramide fibres are used for those parts, such as the inner cockpit shell, which protect the pilot in the case of a crash.

To keep the building costs as low as possible, the wing and elevator halves have a fully symmetric airfoil, so just one mould each is needed to manufacture both the upper and lower shells of these parts. The lightness and strength made possible by this method of construction can be seen from the weight of the wings including the 8.8 Imp gal integrated fuel tank, flap and aileron, they weigh only 36lb each!

The elegant fuselage shows several clever refinements. The front section hosts the compact Mid-West rotary engine, which is installed from the top between the carbon fibre engine carriers. The upper cowling, with its shark-like cooling gills, is held by two spring steel wires, which are pushed in from the front side and locked by snapping them behind a safety plate. Beneath the engine, the air intake and exhaust section is covered with a removable cover. In between engine and cockpit is a ballistic recovery system, mandatory for microlights in Germany. In an emergency, it fires upwards through a lid held on only by clear adhesive tape. The cockpit itself forms a modern safety cell, the basic idea of which has been borrowed from Formula 1 racing car designers. Into the outer honeycomb structure of the fuselage, an aramide fibre cell is fitted. The carbon fibre seat-pan with its stiff backrest to protect the pilot's spine can be removed to enable the control systems to be reached. Behind it, in the rear fuselage tube, a baggage compartment can be fitted, its loading capacity limited by the centre of gravity, depending on the pilot's weight (he sits behind the C of G). The pilot is strapped to the safety cell by a modern four-point-harness, and the cell is directly fixed to the BRS. This is a very safe cockpit, professionally manufactured.

The electrically retractable main undercarriage is hinged at the fuselage and rotates backwards around a diagonal axis. While the 'legs' remain outside at the wingroot bottom, the wheels with their hydraulic disc brakes disappear almost completely into wells which are half in the wing and half in the fuselage. Doors screwed to the legs cover the wheels when retracted. The small covered tailwheel is double-sprung a spring acting telescopically in the fuselage takes the vertical loads, and a rubber block just above the wheel allows it to swing backwards when small obstacles on the ground are hit.

The control system is simple and well-thought-out. Elevator and ailerons are operated by pushrods, the rudder by cables and the flaps via a torsional drive by an electric motor in the fuselage. The spring elevator trim is also electrically actuated. Like a glider, the Silence can be rigged and derigged for hangaring or transport in only ten minutes. Rigging is simple, and, if the fuel tanks are empty, may be carried out by only one person. Once the wings are slid into their slots in the fuselage, one eccentric bolt for each wing underneath the seat pan serves to pull the wings in by swinging the bolt's lever behind the securing spring metal sheet hook. The torsional drive of the flaps connects automatically during assembly, while the aileron pushrods have to be connected to the lower end of the stick by bolts with securing Fokker safety pins. The fuel hoses, the wires of the fuel indicators of both wings and the pitot pressure hose from the right wing are connected by reaching through the undercarriage openings below the fuselage. Finally, the tailplane halves are slid onto the aluminium tube spar ends at the fuselage and secured by a spring steel wire pushed in from behind, the elevator connecting automatically via a hexagon head torsional link. If the rudder has also been taken off, it is inserted from above and secured by two Fokker pins. A look underneath the cowling to check whether there is enough cooling liquid and oil in the reservoirs (the Mid West Harrier uses about 2.5% of the fuel consumed as 'lost greasing oil'), before refuelling the tanks, and the Silence is ready to fly.

The cockpit is easily entered from the front side by stepping onto the tyre and then the narrow fuselage section of the wingroot. After pushing forward the canopy locking lever at the outside fuselage surface, the canopy can be swung open towards the right side. The pilot then slides easily into the well-upholstered, ergonomically-designed, but non-adjustable seat: there is enough space here even for tall pilots. A head-rest had not yet been installed on the one I saw, but this can easily be done. The rudder pedals can be adjusted separately by turning two knobs in the instrument panel: the designers are considering connecting these two knobs together to avoid asymmetric settings. The cockpit's large instrument panel is well equipped. The BRS handle at the front frame is within easy reach and can be secured with a lock. At the left cockpit wall, there is one small fuel cock. In spite of the fact that there are two tanks, one fuel cock is enough because the tanks are inter-connected. The engine takes the fuel from the left tank, which has no ventilation and is refilled from the ventilated right tank. This system is very simple, but comes with the disadvantage of asymmetric wingloading during flight. However, as the tanks are close to the fuselage, this is not expected to greatly affect the flying characteristics. Nevertheless, the manufacturer plans to install separate fuel cocks in later aircraft to preclude the possibility of asymmetric wingloading. The throttle is placed in the spot where you would find the pilot's left hand in a relaxed position. The two buttons for trim operation and also the transmitter button are placed on top of a fighter-like control stick. The trim setting is indicated by an electronic instrument. A knob in the instrument panel serves to set the flaps to 0, 10, 20 or 30°, and a covered switch besides it operates the undercarriage. In case of a failure of the electrical system, there is a red emergency extension handle between the pilot's legs. If this handle is pulled, the undercarriage is disconnected from its spindle drive and then pulled out, assisted by gravity, until it is in the 'down and locked' position. The status of the undercarriage (up, in transit and down) is indicated by LEDs, other LEDs warn if the engine is operated outside its normal parameters, although there are also conventional instruments fitted.

When I test-flew the Silence V2 at Bielefeld-Windelsbleiche airfield on September 5, 2002, it was not yet in final serial condition in fact, it had only made its maiden flight the day before. The wheel covers for the undercarriage legs were not yet fixed in place and the propeller was still a shortened, fixed two-blade Helix unit. The planned three-blade electrically adjustable Silence propeller, already used on the first prototype where it rotates right-hand, was not yet available in the left-hand rotating version needed for the Mid-West. Finally, the engine power was not yet fully available, and resonance problems still required some adjustment to the air supply system.

On closing the canopy, it can be locked by pushing backwards the small knob on the left cockpit wall. The main switch and starter function are united in an ignition keylock similar to that on a car. After switching the key to 'ON', the two ignition switches and the two fuel pump switches beside the key are switched on. With the Mid-West engine nothing runs without fuel pressure, so the second pump is a mandatory safety feature for take-off and landing. With the throttle set to a little above idle, the engine starts immediately on turning the key to the 'start' position. It runs a bit rough below 4,000rpm and only becomes smooth above 4,000rpm typical behaviour of one-disc rotary engines. To protect the ears from the relatively high frequency engine noise, a good headset is recommended. The time needed to warm up is short, and after checking the ignition and fuel pumps, the Silence is ready for take-off. During taxying I found the separate toe brakes effective and easy-to-operate, and the tailwheel, spring-connected to the rudder, easy to steer. By using differential braking, quite tight turns are possible. My eyes were just at the height of the narrow front cowling tip, so I did not need to taxi in a zigzag to get a decent view.

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