| AVIAZIONE LEGGERA ON LINE - IL GRANDE SITO DELL'AVIAZIONE SPORTIVA ITALIANA |
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Low cost, basic and formative ultralights were for a long time considered an unreachable utopia, but the "Tucano Deltatre", even if within well defined operative limits, is at last the first and perhaps unique reality. In fact, this is the first two-seats and ready-to-fly ultralight that comes for less than $10,000 (in January 2001 the price is still fixed at $9,000 including VAT).
For this sum, up today, you could hardly buy a very basic trike without accessories. The plane that we are talking about is a real two-seater with double-commands, effective and formative, very suitable for instruction and with a quality-to-price ratio that doesn't allow objections. The performances are overall good for a tube-and-Dacron plane and consented us to successfully complete the whole CET 2000 raid throughout the Sahara, always at full load, or to use it in its hydro version, for a Côte d'Azur raid during last summer. In a word, this is a basic and extremely simple plane, without any inferiority complexes for the bigger brothers. But let us take a close look to the "Deltatre". The secret? LightnessThe Fly Lab receipt for this extra-cheap plane is simple: starting from the "Tucano" (toucan), by now a super-tested model, with a single-carburettor double-ignition Rotax 503 engine, coupled with a B gearbox.The result is an open, very charming and particularly light machine, with a weight saving of about 95 lbs (kg 40). But this is not all: important modifications have been done to the engine mounts, to the wing dimensions and its position, that has been lowered a few inches, bringing the barycentre of the plane closer to the pressure centre of the wing. On top of everything, a very simple fairing with windscreen, perfectly consistent with the plane philosophy and anyway capable to offer a good protection to the pilots. Is all this sufficient to lower the price below $10.000? Yes and no: the saving is mainly due to the particular building philosophy of the "Tucano", overall simple and using low-cost components, with proper dimensioning. In a few words, taking away all the superfluous, the base structure is surely cheaper than for other ultralights of the same category. There is also a particular commercial policy at Fly Lab, which sells with minimal gains just to support the diffusion of basic flight, affordable for everyone. The name "Deltatre" itself means trike [in italian "delta"] simplicity and economy spirit joined with three ["tre"]-axes capabilities. On boardThe "Deltatre" has its own personality: looking open and compact is perhaps more attractive than his bigger brother (but, for Goodness sake, this is just a personal opinion!), the missing cabin and the new landing gear make the empty plane rest on the tail skid, as pointing the nose to the sky.The pre-flight controls are extremely easy, thanks to the completely exposed structure (all commands included) and there are no substantial differences with the "Tucano". Stepping on board is simple, but since the starter handle cannot be reached from the seat, an external aid is needed to pull it, considering that, for safety, the engine should be never started before stepping in. The seating position is comfortable on the streamlined and correctly padded seats, while the three-points safety belts, if acceptable on the "Tucano", are just sufficient on a completely open plane: to get a firm hold, the buckle must be pulled to the end, otherwise the belt tends to slip from the shoulder with the movements. Instruments: air speed indicator, engine rpm-meter and altimeter are arranged in a row on two simple aluminium rods, in a central and visible position, while the master key (excellent safety solution) and the two ignition switches are placed on a little flask behind the front strut, that is hardly reachable with tightened safety belts. Their definitive position on production planes would be on a small panel under the wing. The brakes work on the main undercarriage and, thanks to the usual central lever between the seats, they could be used for standing (for example while starting the engine). TaxiingNo problems, with a pretty good ground control, a reasonable turn radius and some stiffness in the fore carriage. Unlike the "Tucano" the taxiing visibility is very good, the brakes keep the plane firm up to 4,500 rpm.Taking-off and climbThe take-off run is limited to 120 ft (m 40) with the pilot alone and about twice as much with the passenger (a trike performance or, if you prefer, like a real STOL), the plane readily becomes light and the commands are already effective at low speed.There is no yaw effect due to the propeller and after leaving the runway, the climb is really good: at 44 mph (km/h 70) indicated and 5800 rpm, 500 ft (m 150) are reached in 45 seconds, with a climb rate of about 700 ft/min (4 m/s), as maximal performance at full power. The 503's 48 Hp seem to be effective even with a heavy passenger beside and full tanks. CruiseAilerons: on the roll axis the plane is ready and definitely quick, with limited adverse yaw, and contained bar effort.Rudder: the command is very effective. The induced roll is reduced, and turning just with pedals causes a sensible skid. Elevators: the control on the transverse axis is ready and well measurable, with a right effort on the bar. The lack of a trim-tab is not regretted while cruising at full load, but with the pilot alone a slight and constant forward pressure on the bar is necessary, especially at high speeds. Manoeuvres: the "Deltatre" shows outstanding guts, with incredible prompt responses on all three axes, therefore inviting to a sporty and bright piloting. Weight distribution and lightness make miracles, roll changes are quick and side slips extremely effective (even if the height loss is not very big, owing to the lack of a real fuselage): a real toy that gives you confidence at first sight. Nothing to share with the old generation tube-and-Dacron ultralights, the "Deltatre" is as well formative under this point of view, allowing a good approach to instruction, especially in commands co-ordination, surely more complete. Performances: you just have to choose the power output and the bar position, the cruising speed varies between 50 and 70 mph (km/h 80-110) indicated airspeed, more than this could be obtained applying full power and pushing the bar forward, just to read a little more than 75 mph (km/h 120). A good compromise is to fly at 5200 rpm at about 55 mph (km/h 90) . In the lower part of the gamut, speed drops well below 35 mph (km/h 55) before the controls get stiff and the plane comes to a stall. When this happens, the speed is so low that it seems to be still in the air, recovery is immediate just releasing the bar. Good at turns, just noting that, since the wing is just above the pilot's head, checking the lateral space is not easy. At last, good as well for the little fairing that sufficiently protects pilots up to about 60 mph (km/h 100) indicated, above that the windscreen flexes and air start s getting in from everywhere. Approach and landingSetting out and control are extremely easy, and as well in this case, good controllability consents everything: breathtaking steep approaches with side slips maintained until the runway threshold or engine-assisted long finals that only need small corrections to counteract heat turbulence or crosswinds.The landing roll is always shorter than 300 ft (m 100) at full load (the pilot alone could stop in 100 ft, m 30) and the elevators efficacy (together with the position of the main landing gear) makes possible to touch and keep up the front wheel even at slow speed and engine at idle. Fuel consumptionThe results are very good for a plane with a not quite streamlined design. At full load 4 gall/hr (l 15) are never exceeded and the double tank consents therefore an optimal endurance; with the pilot alone you'd be around 3 gall/hr (l 11) and 3 ½ (l 13) for hydro operations: the choice of the single-carburettor proves to be an excellent compromise between mechanical simplicity, cost and performances.Technical data
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