Fly Synthesis Storch HSJ
PUBLISHED: 12:43 29 June 2011 | UPDATED: 14:08 10 October 2012
This Italian two-seater is a great flyer with delightful handling and many brilliant design touches
By Bob Grimstead
I have just flown one of the nicest aeroplanes I’ve ever encountered. I’ll say that again: of the nearly 250 types I’ve flown, this little wonder goes straight into my top ten.
With all the anticipated Italian attributes of exemplary handling, great performance and brilliant external visibility, the Fly Synthesis Storch just abounds with neat little design touches.
Unfortunately, it’s not currently available in Britain because, while being light enough for our microlight category, it has not yet demonstrated compliance with the CAA’s obsolescent BCAR Section S. It probably does comply, but when Fly Synthesis can sell unrestricted to every other country in the world and are overwhelmed with orders, why would it bother with all that time, effort and expense?
The good news is that with regulation changes currently in progress, since it is already acceptable in several EASA states, it should soon be welcome here both in factory-built form and as a kit. And welcome it should indeed be, because it is a brilliant little two-seater. The Storch’s airframe is stressed to +4 and –2g, and every wing is tested to 150% of those limits before leaving the factory.
Who cares if the undercarriage legs twist at something less than the CAA’s arbitrary limits? (Although I don’t know for certain that they do.) They are deliberately made to bend on a heavy landing so that the airframe is protected and you can see when you’ve over-stressed them. They are easily replaced in minutes, and cost just £25 apiece. The same is true of the nose-leg. Overload it laterally and a pin shears. The
I know of few aeroplanes of any size with such good climb and gliding performance, such light and effective controls or such excellent all-round visibility. And yet, despite its nimbleness, the Storch was never skittish, even in bumpy weather. On my first acquaintance, I wrote along the bottom of my test pad: ‘Delightful! Why can’t they all be like this?’ Low weight combined with high aerodynamic efficiency give the Storch remarkable performance with modest fuel consumption.
The Storch’s tinted Lexan doors are wide and high, bulged outwards to give plenty of shoulder room, and hinged along the top, to lift and clip securely under the wings.
There are three simple rod latches, neatly operated together by twisting a single, central knob through ninety degrees. SUPRISINGLY ROOMY
Entry is dead simple. You just back up and sit on the seat, and then swing your legs up and forwards into the footwell. Each seat has four fore-and-aft positions, and easy adjustment by popping out a pin, sliding them to the required position and then pushing the pin back into place.
The cockpit is surprisingly roomy, with lots of headroom and plenty of shoulder space, being a whopping 44 inches wide. Behind the seats is a fairly generous baggage area, carrying up to twelve kilos.
You sit close to the floor with your legs stretched out, but the position is comfortable,
and the seats have good lumbar support despite their rather thin padding, with fixed four-point harnesses. The curved control columns have quite a long travel, remarkably low static friction and comfortable foam grips.
The rudder pedals are simple steel tube fabrications, operating through dual push-pull Teleflex cables, and steering the nosewheel through a direct linkage. Instead of separate ailerons and flaps, these are combined in full-span ‘flapperons’. One goes up and the other down when you move the stick sideways, and both sides droop to double up as flaps.
The cockpit transparencies are enormous, making visibility better than in many helicopters. Instruments occupy a neat and elegant, helicopter-like central binnacle which is mounted low, completely out of the way of your external view.
Across the middle are the ASI, VSI, altimeter and tachometer, with engine gauges below, and the slip ball at the very bottom, while the intercom and radios (a Micro Air VHF and Mode C transponder) run above them with the compass on the very top.
A handheld GPS is bolted externally on the binnacle’s far right (presumably so an instructor can check your navigation) and there is a pair of useful zippered stowage bags on the floor against the outboard sidewalls.
On a vertical extension below this binnacle are the carburettor and cabin heat knobs, magneto and master switches and starter button with, below them, sideways rocker switches and fuses for the various electrical services (including that refuelling pump – see sidebar). Behind this and between your knees are two small quadrants in tandem.
The front one holds the lightweight plastic throttle and smaller choke lever, while the rear one carries a pair of similar but intermediate-sized plastic brake levers. There is no parking brake; the quadrant’s adjustable friction holds these levers sufficiently firmly to prevent the aeroplane moving forwards until significant power is applied.
Aft of the brakes are two separate fuel taps, one for each tank, and the fuel quantity is read from three transparent windows in the wing root tanks. Behind and between the pilots’ heads, the flap lever protrudes forward from the rear bulkhead.
Its latch is released by pulling forward on either of a pair of big triggers half way along it, and there are three flap positions: ‘up’, ‘fifteen’ and ‘thirty’. The headset plugs are immediately above it, so this lever makes a handy place to hang the headsets on the ground when it is set to the mid position. In front of this, the tail trim lever hangs down from the wholly transparent roof and is set with its forward edge vertical for takeoff.
Starting is standard Jabiru. Even with the throttle fully closed, this eager little aeroplane soon moves forward under idle power. The nosewheel steering is very light and the turning circle is surprisingly tight.
Considering it is just a pair of aluminium rods, the undercarriage is surprisingly soft and comfortable. Although unusual, the independent hand-operated brakes work very well. It is easy to apply them gently either together or one at a time to further tighten the already small turning radius. Held firmly, they comfortably restrain the Storch against run-up power.
Pre-takeoff checks are simple and quickly accomplished. Takeoff is normally made without flaps, although the first setting (fifteen degrees) is recommended when flying from grass, soft ground or in calm conditions. The first time I flew, the wind was along the runway at ten knots and the temperature was a warm thirty degrees Celsius. With two big guys aboard, we limited our fuel to 45 litres to stay below maximum weight (although that is still enough for nearly four hours’ flying).
Resting my wrist on the brake levers served the dual purposes of supporting it while I operated the throttle, and ensuring the brakes were definitely fully off for takeoff and landing.
Open the throttle, and even with two aboard the Storch simply zooms forwards. You need just a squeeze of right rudder to stay straight, but not for long, because she’s airborne so quickly – in maybe 100 metres at little more than forty knots. Solo and in anything of a headwind, the ground run is nearer fifty metres, and it’s over before you can think about it. The published climb rate at full weight is nearly 1,000 feet per minute, and significantly more than that one-up.
Off a 1,200-metre runway you can expect to be level at a thousand feet well before you get to the far end! The stated best climb rate airspeed is 59 knots, with a best angle speed of 43 knots, but sixty knots is more than adequate for most purposes. Neither cooling nor forward visibility are a problem; sixty is just an easier number to remember. At that speed, and at maximum weight on our hot, bumpy first day, I timed our climb from 400 to 1,400 feet at 700 feet per minute.
The flying controls are lovely – light, almost dainty, while being very effective and well harmonised. In fact, the controls are so light it is difficult to judge which axis is heaviest and which lightest, they are all so similar. Just a little rudder pressure is needed to balance turns, which is ideal in my view. And despite such responsiveness, the Storch is not at all skittish, and stable in all axes. Pitch stability is very positive, but not so much as to hamper controllability.
The aircraft is less stable in yaw, partly because of slight friction in the system, which probably comes from the nosewheel rather than the rudder. In roll, it is again stable, but only just, which is quite normal. Full span flapperons give the Storch a good roll rate for its span despite its rectangular planform. The visibility through those big roof panels becomes invaluable in tight turns. Circling at eighty knots and sixty degrees of bank, the view is outstanding in all directions.
This would be a superb observation platform. What is particularly odd (and very special) is that, with these light and really effective controls, there is no sense of ‘twitchiness’ – quite the opposite in fact; the Storch quickly imbues a sense of confidence, and I am not surprised students are tending to solo the Storch rather more quickly than in some other types. Even in turbulence, and despite its very light weight and low wing loading, it is bounced about much less than many other ultralights I have flown.
It is no slouch in the cruise either. Leaving the throttle wide open at 4,500 feet, we saw 102 knots IAS (107 knots TAS) at 3,200rpm, 96 knots at 3,000rpm and 77 knots at a rather quieter 2,600rpm. Jabiru quotes a fifteen litre per hour fuel consumption at 75% power for this engine, but I am assured they burn on average less than ten litres per hour during training, and this particular example used just twelve litres per hour at a steady 100 knots on its trans-continental delivery flight. Fuel consumption is dependent on a number of factors, particularly the coarseness of the propeller pitch.
Slowing right down, the controls could barely become much lighter, but they were all still effective right down to the forty-knot stall. There was just the tiniest buzz of warning buffet a knot or so before the break, which was only a very slight nod. This aeroplane will teach students to keep the slip ball centred though, because if it is slightly off to one side, it will gently drop a wing, although only by twenty degrees or so, and the wing drop is promptly arrested by applying appropriate rudder.
The behaviour was similar with fifteen degrees of flap, and still innocuous, at 38 knots. The stall speed dropped even further to 35 knots with full (thirty degrees) flap, and the Storch’s manners were still impeccable. Recovery was instant once the stick’s back pressure was released, and our total height loss in each stall was less than a hundred feet.
My instructor demonstrated that it was possible to induce a proper pitchdown by heaving the nose up for a quick speed reduction, but that is unlikely to happen by accident.
What particularly impressed me was the remarkable low-speed aileron control from those flapperons once they were drooped as flaps. Most flapperons I had previously experienced suffered from severely degraded roll control once drooped as flaps. Yes, the Storch’s ailerons were a bit less effective with the flaps out, but not much, and they were not significantly heavier to operate, which was particularly pleasing.
The corollary to this is that the flaps do not produce an awful lot of drag. Indeed, the
Storch glides so well it could almost qualify as a powered sailplane, despite Fly Synthesis quoting a fairly common nine-to-one glideangle.
I am not alone in having had trouble descending on base leg when there were thermals around. Even with full flaps, I had real difficulty getting down during our practice forced landing. Of course, you can sideslip (yes, even with full flaps) and the effective controls allow a good yaw angle, but the fuselage is so skinny and rounded that there is very little drag increase, so the descent is not greatly steepened. Because of this, I found it easiest to make all my approaches with full flaps and the throttle completely closed, modulating our descent angle with sideslip as needed (and the glide angle is so shallow I still felt as if I was dragging our wheels through the tree tops).
The recommended approach speed is sixty knots initially, reducing to 55 on final and fifty over the hedge if it is not too gusty. The aeroplane is so light and the elevator is so effective that you can get right down to head height before flaring. And at these low speeds there is not much float, although if you come in a bit fast you can gobble up a hundred metres or so bleeding off excess speed.
The elevator is still very effective during the hold off, so care is needed not to overcontrol; indeed, it is possible to keep raising the nose higher and higher for a proper, minimum speed touchdown. The undercarriage is very forgiving, flattering all my landings. Even after the main wheels are on the ground, you can hold off the nosewheel until the aeroplane is almost stopped (although you do need to be sure it is centred before it grounds if you don’t want a brief few seconds of excitement).
Takeoff and landing performance are definitely STOL, and I found it simple to touch down and stop by the first runway turn off, little more than fifty metres in from the threshold. Takeoffs can easily be made in even less distance. I was very impressed by this lovely, agile little aeroplane, and thoroughly enjoyed flying it. It has superlative, unsurpassed visibility, excellent performance at low cost, and delightfully light and yet capable controls.
Builders report that, as currently delivered, the kit-built Storch ideally needs either previous building experience or a completed aircraft to copy, because the kit comes with lots of small plastic bags full of unmarked bolts and nuts. Also the construction sequence is not always optimum, while the book is mostly a series of photos, and not always very usefully captioned. However, I am assured that the company is aware of these criticisms, and improvements are already being implemented.
The Fly Synthesis Storch may not have the looks of an Italian supermodel, but she sure is a little beauty to fly!