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The rudder-connected tailwheel feels very direct and allows for precise and easy taxying, though the turning circle is not particularly small. The prototype I flew four years ago was equipped with separate toe brakes, permitting smaller circles, but requiring much more skill during take-off and landing, and resulting in the small tailwheel's rubber tyre wearing out quickly. The bike-type lever in front of the stick operates the brakes, and they are almost effective enough to prevent the powerful Comet from creeping forwards at full throttle. There is very little risk of hitting the Ducaine three-blade composite propeller, due to the high tailwheel loading, while the only thing I missed was a parking brake function. Before doing my final pre-flight checks, I push the canopy forward until its pins slide into their holes in the front windscreen frame, this is then locked into place with a lever above the instrument panel. I checked the horizon position relative to the cowling, and committed it to memory I'll need it later on to make a proper landing. The handbook gives the '+1' flap position for normal take-off and landing, but Peter told me that he found the '0' better suited to solo flying.

With my 176lbs aboard, the CG is neutral to slightly tail heavy, so I decide to leave the flaps up. It is not sensible to lift the tailwheel too early if you have a powerful engine, so I set the trim to neutral and kept the stick in the centre. The Comet accelerates fast shortly before it lifts off the ground the tailwheel does so thus requiring a light application of right rudder to keep it running straight. I detected no noticeable difference in the climb rate between 55 and 70kts, so trimmed for 65kts. Although the weather was very hot, I needed only 2 min 40 sec to climb to 3,000ft above Speyer airfield nearly 1,200ft/min, which is an excellent climb rate.

During the climb, all the engine temperatures stayed well within the green arc, and there was still some reserve left in the Rotax's cooling system, as a section of the radiator inlet was covered by tape. The cruise speed at full throttle settled at a bit above 100kts with the Rotax running at 5,350rpm, still well below the max continuous of 5,500. With the throttle reduced to about half, the ASI indicated 89kts at 4,900rpm, a comfortable and economical cruise setting. Unfortunately, the fuel flow indicator failed during my flight, so I cannot give precise consumption figures for these power settings. After my one-hour flight, there were three gallons less in the fuel tank an average consumption rate for a100hp Rotax. Although the fuel tank cannot be seen from the rear seat, it is possible to have a look at it in flight after loosening the shoulder straps and bending forwards a bit.

Setting the trim properly was difficult--I think the Bowden cable for the Flettner trim tab shows a bit too much elasticity combined with friction, resulting in an imprecise feeling. Peter told me that he is going to improve this. The trim adjustment was also not yet perfect in this aircraft, which had only been flown for a few hours. The foremost position I needed during cruise flight left the trim knob roughly in the centre of its travel I would have liked a bit more aft trim than is currently possible for slow flying with the engine running at idle or the flaps set. This should be easily rectified. Trimmed properly, the Comet flies straight 'hands off'; the aileron and elevator forces rise proportionally with the speed, while the rudder forces remain relatively low, even at high speeds. The power setting - trim speed connection might still be improved a little with the power reduced, the nose goes down and the trim lever arrives at its aft stop at a speed of 60kts. Setting the flaps results in a further nose down moment, which has to be compensated for by pulling the stick back to prevent the Comet from flying faster than the 65kt flap limiting speed.

As with any powerful tandem seat aircraft flown from the rear seat, the cowling is high above the horizon during climbing, but the visibility from the cockpit is good and almost unobstructed by the upper wing. The two 'window bubbles' supply enough fresh air to the cockpit, and they are both within easy reach of the pilot. The cabin-heating inlet is in front of the front stick due to the hot weather I did not to test its efficiency. Externally, the noise output is very low (the German certification rules are especially strict concerning this); in the cockpit it is acceptable, but nevertheless a good headset should be worn.

The stall behaviour, which was not very satisfactory in the prototype, is now quite gentle. With the engine running at idle and the flaps at '0', the stick starts feeling soft at 38kts IAS; at 37 buffeting can be felt, and at 36kts you start to enter a stall with the tendency to drop a wing. This initial wing drop can be stopped immediately by applying opposite rudder, even with the stick remaining in its rear position. With the flaps set to '1', the indicated speeds are about one knot slower, another two knots less may be flown with the flaps set to the '2' position. Now the tendency to drop a wing is less, instead the Comet wants to drop the nose and accelerate. Stalling the Comet with the engine running full throttle results in the nose pointing steeply upwards you might think about whether it's possible to hover it hanging underneath the propeller. With no flaps set, the indicated speed decreases to 32-33kts. With the help of the rudder a wing drop can again be avoided efficiently. With the flaps set, the minimum speed indication drops to about 27kts.

As expected for a biplane with ailerons on all wings, the roll rate is extremely fast. Flying at a speed of only 54kts, I measured an average time for the 45° to 45° bank change of 1.8 seconds. The control harmony is also excellent even these fast rolling manoeuvres at slow speed are possible without sideslipping when using full aileron and rudder. But there is a situation you should be aware of if you intend to 'play' like this in a Comet the inertia of the fast-rolling aircraft should never be forgotten: If you stop the rolling movement by just rapidly applying opposite aileron, the descending wing with the aileron deflection, now changing to 'down' position, may stall. This can result in the rolling movement continuing as a snap roll with a slightly slower roll rate than you had achieved before with the ailerons fully deflected in the rolling direction. A kick on the rudder pedal against the rotation direction accelerates and unstalls the wing immediately and stops this movement no problem for pilots who have proper spin training, but potentially a hazard for inexperienced pilots who try to show off the Comet's crisp handling close to the ground.

For the landing, I chose the '0' flaps position as recommended by Peter and approached the airfield at 55kts. The sink rate with the engine running at idle permits normal approaches, although such a biplane likes to be sideslipped, not only because you can achieve steep, safe approaches, but also obtain an optimal view of the landing area, unobstructed by the long cowling in front of you. Close to the ground, the Comet is held off until the nose points a little bit higher than it did on the ground before take-off (now you know why it is wise to remember this position before take-off...), the wings are levelled and the rudder centralised shortly before the moment of touchdown. This method results in smooth landings without any ballooning. If the speed is still high, the rudder with its directly connected tailwheel should be operated very carefully with only small deflections. The wheelbrake operates smoothly and is effective without a tendency to nod the nose down again much easier than it was with the prototype's separate toe brakes. Pilots experienced on taildraggers should have no problem landing the Comet, even in a crosswind, but pilots trained on simple microlights with tricycle undercarriage may need additional training.

The FK-12 Comet should fit the bill if you're looking for an open-cockpit biplane that provides fun in the summer, while the closed canopy enables it to serve as a fast and comfortable cruiser during the rest of the year. It is a safe, straightforward and relatively easy to fly aircraft. It is clearly not intended to be used as a basic trainer, but is suitable for conversions and for learning a bit more about taildragger flying.

With a basic price of just below 50,000 Euro (with the 100hp engine, exclusive of VAT, rescue system and other extras) the price is in the range of similar powered modern microlights. If you opt for some of many extras you encounter the same payload weight problem that affects nearly all modern two-seater microlights. However, the maximum design all up weight retains options if the legal weight limit should be increased or if customers decide to buy the pre-fabricated B&F kit (resulting in saving up to 10,000 Euro). Then they may certify the Comet as a homebuilt 'Experimental' aircraft. Finally, I have to admit that this nice two-seater microlight is one of those aircraft that really is a lot of fun to fly -- what more do you want?

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