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This Silence weighs exactly 441lb empty. With me in the cockpit and 11 Imp gal of fuel (standard 92 oct car fuel), it weighs 683lb: even with full tanks I would still be below the maximum permitted 750lb. The centre of gravity is in the forward range. For take-off, I turn the flaps knob to 10° and set the trim to neutral. After pushing the throttle forwards until I reach 1cm behind the front stop (because of the resonance problem mentioned earlier, the engine starts coughing with more throttle), I accelerate quickly with the stick held slightly forward. As soon as the tailwheel lifts off, I need a small amount of left rudder to compensate for the propeller torque. At 43kts it lifts off, and I let it accelerate to 60kts before starting to climb. At a safe height I retract the undercarriage, set the flaps to 0° and switch the second fuel pump off. In this clean configuration, I find the best climb rate at 65kts, and although the engine performance is not fully available it climbs at about 790ft/min. With the engine problem solved, I expect the aircraft to climb in excess of 1,000ft/min. The heavier prototype with the 65hp engine which I flew in the spring climbed at nearly 1,180ft/min. Trimmed to the best climb speed of 65kts, only a small amount of left rudder is needed to keep it flying straight. On reaching 2,500ft, the engine's three minutes of permitted full power operation have passed and the cooling liquid temperature comes close to its maximum. I reduce the power to the maximum continuous setting of 7,100rpm and continue climbing at 70kts, with the result that the temperatures remain in the green arc.

During cruise flight, this rpm limit is already reached at 86kt with the current Helix propeller. The prototype, equipped with the Silence-developed three-blade variable pitch propeller, reaches more than 108kts with no problems. In this aircraft, and probably also the Mid West-powered ones equipped with the new propeller, the 17.6 Imp gal of fuel makes possible 620-mile flights at a cruise speed of around 100kts.
I am particularly impressed with the handling of this little aircraft. The control forces remain very low, though positive, for just about the whole speed range. The Vne of the 'Experimental' version is calculated as 162kts, though it is only 140kts for the microlight version due to the limited operating speed of the BRS. The sensitivity of the Silence gives the impression of flying a fully-aerobatic aircraft, and trimmed to cruise speed it flies beautifully stable in the 'hands off' position. However, if the right fuel tank is empty and the left one full, a small amount of aileron deflection is needed to keep the wings level. These excellent general handling characteristics are further supported by the excellent view through the big canopy and the good fresh air supply through the nozzles in the front cockpit frame. Cabin heating is also installed, though in the current warm weather I feel disinclined to test its efficiency. The only thing I miss is a small 'direct-vision' panel in the canopy I once experienced outside cabin icing when descending with a cold glider through an inversion layer into warm, humid air, and opening this window then saved me from being 'blind' and lost... How does such an elliptic, fully-symmetric wing behave when it is stalled?

I was quite astonished at the gentleness of the stall. With the engine running at idle and the flaps at 0°, the Silence's controls start feeling soft at 43kts: at 40kts the stall starts buffeting and speed increases to 43kts again in the staggering stall, where it can be held by using the rudder. With the elevator further back, staggering increases and I start feeling as if I am sitting on a wild horse, though I can still prevent it from departing into spin with the rudder. I think this effect is caused by the turbulence separating behind the wingroot (which was probably stronger than usual due to the uncovered retracted wheels underneath the wing) hitting the tail. With its forward C of G position, the Silence starts dropping the nose, but immediately the airflow comes back to the tailplane, the game starts again.

Setting the flaps results in the same behaviour, with the minimum indicated speed decreasing by about 2kts per 10° of flaps set. With full throttle, the indicated speeds are again 1kt lower. The ASI of this aircraft had not yet been calibrated and seems to over-indicate slightly with the prototype, a calibrated airspeed of 35kts at 750lb AUW has been demonstrated during the certification. When I flew this prototype with an aft C of G and the wheel covers fitted, the staggering was less pronounced. It did try to drop a wing, although the incipient spin could be stopped immediately by relaxing the stick and applying opposite rudder. The Silence shows excellent control harmony. With the engine running at idle and trimmed to 70kts, it raises the nose and starts climbing at 65kts once the throttle is opened fully. Setting the flaps (below 65kts) to different positions does not really influence the trimmed speed. Its roll rate is impressive: when full rudder and aileron are applied, even at the slow speed of 59kts it rolls from 45° to 45° bank within 1.5 seconds without sideslipping. This roll rate is practically aerobatic, and care has to be taken not to stall the lower wing when applying full aileron and not enough rudder against the rolling direction. But even in such a situation the Silence is straightforward a kick into the rudder against the rotation direction stops the initial snap roll immediately.

The manoeuvring speed, up to which full control deflections are permitted, is 97kts, and the maximum allowed speed to fly through stronger gusts is 119 kts, clearly above cruising speed. Compared to other fast microlights, in which you should cut your flying speed considerably when flying on a day with strong thermals, this gives a good margin of safety. Of course, these flying characteristics may tempt some to try a few aerobatics. However, the rules of the microlight category set clear limits aerobatic are generally prohibited in these aircraft. Anyone with ambitions in the direction of aerobatics could always buy the strengthened kit Silence Aircraft offers. If the builder completes it at home and certifies it as an aerobatic aircraft in the 'Experimental' category, there are no limits to gambolling around the sky (and probably outclassing the Tipsy Nippers and RF-4s you can hardly ever find in the second-hand market...).

The electric flap drive acts rapidly. Within three seconds the flaps reach their maximum of 30°: the undercarriage needs 7.5 seconds for retraction and 9 seconds for extension. The maximum speed in landing configuration with the flaps set to 30° is limited to 65kts. Under calm weather conditions, I find an approach speed of 56kts comfortable and perfectly safe. Before landing, I switch the second fuel pump on again. The flaps are effective, and with the engine running at idle it is easy to control the glidepath. Sideslipping is very easy and effective, permitting very steep approaches and further improving the pilot's (already good) view of the runway it also feels as if it's the right way to land an aircraft resembling a Spitfire!
Provided you stopped sideslipping after holding the Silence off until the nose was at the correct attitude, and that you centralised the rudder before the wheels touched the ground in a proper three-point attitude, the Silence will land gently. If you do not follow the advice given above, it will 'dance'

a little on the runway, due to the un-damped, but sufficiently sprung undercarriage. Even a strong or gusty crosswind causes no problems, though some taildragger experience is useful to produce a good landing on a concrete runway (and to keep the aircraft there afterwards!) For new Silence pilots, I would recommend making your first few landings on a more forgiving grass strip. The rudder has to be used carefully during the ground run the separate toe-operated hydraulic disc brakes are easy to use and quite powerful. As the main undercarriage is well in front of the C of G, the risk of nosing over is relatively low.

As a single seater of the upper microlight class, the Silence is not for everyone, and it does require the pilot to have a certain level of taildragger experience. Flying it is enormous fun as it offers a high level of performance combined with excellent safety features. The Mid West 'Harrier' single disc rotary engine suits its slim appearance, though it consumes a relatively large amount of fuel and is not the smoothest of engines, particularly at low rpm. With this in mind, Silence Aircraft is considering equipping the aircraft with the 75hp Walther Minor IIIB air-cooled in-line four cylinder engine. Used as a microlight, the Silence's operational range is fairly limited by the definition of this aircraft category however strengthened versions certified in the 'Experimental' category, built at home from a pre-fabricated kit, may be used for aerobatics and show the full range of this design's abilities. The great interest that these first 'little Spitfires' attracted whenever they appeared demonstrates clearly that a large market is out there waiting for the Silence!

On reaching 2,500ft, the engine's three minutes of permitted full power operation up to 7,750rpm have passed, and the cooling liquid temperature comes close to its maximum. Reducing the power setting to the permanently permitted 7,100rpm and continuing climbing at 70kts results in the temperatures staying in the green arc.Right Straight from the box the kit is well-produced and has the benefit of considerable prefabrication.

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