French Kiss - British Microlight Aircraft Association

More documents

Recommendations

Info

The front forks with the oleo-damped wheel assembly turn in what amounts to a large hole in the bottom of the pod - no draught excluders here! However, a moulded fairing around the hole really does stop the wind blowing around up your ankles in flight. Paul Dewhurst said it would and it does! The trike has other, finer design touches. The starting battery (electric starting for the 582 is listed as an optional extra which, in my opinion, amounts to a screaming necessity) fits within a recess at the bottom of the HDPE plastic fuel tank moulding with the trike keel taking the weight of the battery. The three-point engine mounting virtually eliminates perceived vibration from the watercooled engine. The unit is mounted at a slight slant along its axis to offset the propeller torque reaction on the mounting rubbers by virtue of its own weight. The notable lack of in-flight vibration is also probably helped by the slow-turning three-blade propeller driven through the 3.47:1 reduction ratio E-series gearbox. It makes the aircraft remarkably quiet when witnessed either from the ground or from the pilot's seat. The cooling system also has a nice touch: the radiator is mounted horizontally below the trike within a moulded cowling, forcing air downwards through the matrix. Wire mesh keeps out the crap. Cockpit instruments are mounted into a fairly small front panel with little room for more than the basic flight and engine necessities. But this is very much part of the machine's Gallic heritage. The French really do think that British trike flyers are a bunch of fairies for wanting any kind of weather protection, never mind instrumentation… Sizewise, cockpit accommodation is definitely on the cosy side when flying two-up but near perfection when flown solo. The pilot leg room suits me perfectly but then at 5ft 9in I'm not much of a design challenge. However, with Paul Dewhurst in the rear seat, I think that we both experienced a degree of intimacy unusual outside the realm of consenting males. At 6ft 2in and 95kg, Paul is definitely not built to Section S. The wing Apart from being visibly small for a two seater machine, the wing planform looks in no way unusual. But then, as with so many aspects of this French machine, interest is in the detail. For a start the principal sail surfaces includes Dyneema filaments within the weave creating a material of much greater intrinsic strength than that of pure Dacron. Dyneema is a proprietary high performance polymer made by the Dutch chemical giant DSM and enjoys similar tensile characteristics to Kevlar. Leading and trailing edges are reinforced with a laminate for architectural stiffness. The sail retains a beautiful cut both on the ground and in the air without any sign of wrinkling or, Heaven forbid, flapping. The undersurface occupies some 80% of sail area and connects to the upper surface by a flexible neoprene tie strip along its entire trailing edge allowing a degree of relative movement between the upper and lower surfaces for controlled aerolasticity. A further tie system between upper and lower surfaces is located deep inside the wing chord close to the leading edge. This arrangement gives a positive servo assistance to roll inputs making the machine demonstrably light to handle in the air. Air Creation has provided a neat finishing touch at the wing tips with caps between upper and lower wing surfaces held in place by Velcro fastenings.
23 top surface and 12 undersurface batons maintain the wing profile. The batons are retained in their pockets by ordinary cord rather than the ubiquitous bungee. According to Dewhurst, the dimensional stability of the sail material obviates the need for a flexible baton retention system. Certainly the machine flies straight as a die in the air. Should a turn ever manifest itself, it can be tuned out by rotation of the sail attachments at the wing tips. Structurally speaking, the wing holds no surprises. Interest is once more in the detail. For instance you won't find a bolt through a bit of ali channel hinging the crosstubes to the leading edges. This French machine uses a purpose designed complex hinge giving a controlled movement in three axes. The hinge components are individually machined from solid metal. Having said this, I rather like the simplicity of a simple aircraft quality bolt at this lifedetermining position. The trim system shows the same attention to quality and detail. The trim knob on the A-frame uses integral gearing to ease use in the air while wearing thick gloves. The system acts on the middle luff lines only but this is sufficient to take 10mph off the 60mph untrimmed airspeed. The airframe uprights have been faired with clip-on profiled coverings offering a neat, structurally neutral solution to draggy tubes. Some enterprising chap should offer them for sale to those of us with older trikes: I am sure that there would be quite a few buyers for such a simple solution to an old problem. In Flight With Paul Dewhurst shoe-horned into the back seat we commenced taxiing to the easterly holding point at Sywell. The massive foot-shaped pedals for brake and throttle are also the footrests and operating them smoothly does take a bit of practice. Ground steering is satisfactory - very little wallowing on the suspension - although the drum brake on the front wheel is not progressive and tends to snatch. Lined up and cleared by the Tower, the excitement begins. The first thing you notice on opening the throttle fully is how leisurely the 582 sounds. Although it pulls 6200rpm, the big reduction on the slow-turning prop made me wonder if I had opened the throttle fully. The next 100 metres of travel down the slightly bumpy grass strip dispels any doubt with the machine rotating decisively at just over 40mph IAS. You know instantly that the machine is a good one. It leaps into the air in an absolutely straight line and the pilot becomes immediately aware of the positive forward bar pressure required to keep airspeed down to 50mph for best climb performance. And what performance! The Kiss had no trouble sustaining a timed 700fpm at the maximum legal takeoff weight of 400kg. Indeed, it mostly pushed 800fpm fully laden. And it wasn't the sort climb rate that required a bit of nudging and scratching around the heavens together with a scrupulous eye on airspeed to maintain. The machine achieved this climb effortlessly and repeatably. I couldn't wait to get the thing back on the ground to boot Paul out and see what a French Kiss could really do. Also, I found that his long legs were projecting so far forward past my shoulders that I couldn't really pull the bar in far enough for fun without giving him a kneecap job. Before this, there were other things which this machine absolutely begged you to try. Blade and Q(uantum) pilots would be totally familiar with the fully laden pitch response of the Kiss - reassuringly positive and disappointingly heavy. It needs real muscle either to hold the bar into your chest or outwards against the front strut. Heaving the bar in returned a sustained IAS of 85mph while straining to keep the bar against the front strut brought the indicated airspeed down to 40mph without any sign of an imminent stall - both figures obtained at 400kg flying weight. The engine seemed fairly leisurely in the cruise. With the trim control set at fast giving a handoff indicated airspeed of 60mph, the rev counter showed 5000rpm. I would guess - and it is only a guess - that the power setting would equate to about 12-14 litres/hour. Winding up the trim control took about 10mph off the airspeed but I can't imagine why anyone would really want to do this in a machine built for going places. Opening the throttle on most machines while straight and level normally produces a climb with little change in indicated airspeed. The Kiss is unusual. Opening up the throttle puts about 10mph on the airspeed and requires a pilot input to convert all the added power into climb. This isn't a problem, just a noticeable difference. The roll response is probably the lightest that I have ever come across in a two seater flown two-up. It acts both rapidly and positively and probably requires about half the effort required
Page 1 and 2: French Kiss Frank Ogden The Kiss is
Page 3: There is a serious point about fuel
Page 7 and 8: oll characteristics. As a single se

French Kiss - British Microlight Aircraft Association

Create successful ePaper yourself

Delete template?

Save as template?