The Frati/Sequoia Falco F.8L
by Peter Underhill
This "Editor's Air Test" appeared in the June 1990 Popular Flying, published by the Popular Flying Association, England's equivalent of the EAA. The Falco tested had one year before won the PFA's Best Homebuilt Award.
The F.8L Falco first became available in kit form, and thus to the notice of PFAers in the early 1980s. Prior to that event few UK aviators had paid much attention to the work of a man who is one of the most gifted and talented of small aircraft designers, Stelio Frati. Whereas the talents of those equally gifted Frenchmen Delemontez and Joly have become widely known through the popularity and large production volumes of the various Jodels and Robins, Frati's designs seem to have been almost completely overlooked, as few have ever been built in serious quantities. Considering their exceptional performance on low-powered engines, their superb handling, general overall efficiency and absolutely gorgeous classic Italian styling, on a par with the finest Ferrari or Lamborghini, this is a sad reflection on the Italian general aviation industry.
Stelio Frati was born in Milan in 1919. Since childhood, he has been "plane-crazy," and became Italian National Champion free-flight aeromodeller in 1940 whilst studying at Milan Polytechnic between 1938 and 1943. Because there was no aeronautical section, he qualified as a mechanical engineer and contributed to the design of various sailplanes, the AL12 military glider and the wondrous Assalto Radioguidato, a kind of "flying bomb" powered by a radial engine. The pilot was supposed to perform the takeoff, jettison the undercarriage, bail out and leave the "aircraft" to be directed towards the target-Allied shipping in the Med-from another aircraft by radio control.
In 1944, after the war in Europe finished, Frati returned to his old school-now with a aeronautical section-as deputy to his old professor, before becoming a freelance designer in 1954. His philosophy was similar to Delemontez and Joly, namely to produce and refine a design, then to sell production licences to any company that wished to take them on. Compared to the French, the Italians are not quite so air-minded so, with a few notable exceptions, few of his designs went into serious production. Whether some were just too esoteric for the marketplace or too labour-intensive to allow profitable production can only be a matter of speculation. This lack of "product visibility," prior to Alfred Scott's launch of the homebuilt Sequoia Falco kits and plans, undoubtedly contributes to the fact that contemporary discussion on the Falco invariably centers around Scott's involvement. If Frati is mentioned at all, it is usually to wonder what else he has done.
Yet so many of Stelio Frati's designs have such style and panache that one wonders why more attention hasn't been paid to his creations. For truly, no-one else-including Burt Rutan-has managed to create such a wide variety of smooth and beautiful aeroplanes capable of such speed on such low power. His early ventures began-leaving aside a rather ugly motorglider-with the F.4 Rondone. An all-wood 2 seater with a Continental C85 engine, the prototype F.4 was capable of 160 mph. Approximately twenty were built by Aeronautica Lombarda and Ambrosini using the uprated C90 engine, and one example held several world speed records in the early '50s, achieving 169 mph over 100 km distance! Only two remain airworthy today, but what a superb homebuilt it would make, being rather simpler to build than the curvaceous Falco.
The prototype F.8 Falco (the name is Italian for "Hawk") first flew in 1955. It was originally designed around that omnipresent Continental C90, but production versions (designated the F.8L-the L for Lycoming) had more powerful engines. Several manufacturers built small number of variants, almost all with government subsidies, which were supposed to be returned if a Falco left Italy. More than one intending purchaser of a second-hand I-registered Falco has experienced total frustration at the hands of the Italian bureaucracy whilst trying to discover to whom he owes the subsidy repayment.
For those PFAers who have neither the time nor the requisite lire to contemplate such an action, but who still want to possess a Falco, the appearance on the scene of Alfred Scott and his Sequoia kits must have seemed a god-send. If anyone who bought one in those early days was taken in by comments like "easy to build," the story of G-BYLL is a salutory lesson. It took almost six years of hard graft by three men to reach the stage at which it won the coveted award at Cranfield.
Christopher Langrick, Bill Nattress and Neville Langrick.
Neville Langrick first became interested in the Falco some 15 years ago, after a trip in a production version. In 1982, together with Bill Nattrass, he purchased a set of Sequoia plans, and the project commenced. Bill made much of the hardware in his shed using a vintage Myford lathe, whilst the woodwork was also homemade. Later, as the aircraft progressed, the duo were joined by Ray Holt. He took on the finishing task, spending many hours "rubbing and filling" and designing the beautiful and unusual paint scheme which uses a General Motors 1965-vintage "stone beige" with dark brown stripes. The finish is to Rolls-Royce standards, and this extends to the use of Connelly hide, West of England broadcloth and Wilton carpets in the interior! The aircraft is powered by a Lycoming 0-320-A3C and is very comprehensively equipped in the avionics/instrumentation area. It finally tipped the scales at 1280 lbs, about average for a homebuilt Falco.
The aircraft was registered G-BYLL in recognition of Bill Nattrass's contribution, and first flight took place from Sherburn-in-Elmet on June 7, 1988, in the hands of ex-Lancaster pilot "Jacko" Jackson. It became the 16th Sequoia Falco to fly world-wide. Unfortunately, testing and paperwork were not completed in time for an attendance at Cranfield that year, but offsetting that minor disappointment, the trio were able to avoid the usual rush which often precludes a "first appearance" at our premier event.
During the autumn of '88 and the spring of '89, many enjoyable hours were flown to gain confidence and familiarity. In June 1989, Ray Holt took the Falco to the Malta Air Rally, arriving back only a few days before Cranfield, where several thousand PFAers were able to see for the first time the beautiful, sleek, curvaceous and just downright sexy lines of G-BYLL!
Some six weeks after Cranfield, the seemingly impossible simultaneous combination of the Falco, a suitable camera plane and pilot, photographer Gordon Bain, and a whole heap of perfect cloudscapes, all arrived in the same place at the same time, and I was able to conduct my evaluation of the Falco, and also give Gordon the opportunity of some air-to-air photography during the test.
So how does the UK's first homebuilt Falco perform? In a word-magically!
The 1989 winner of the Popular Flying Association's Best Homebuilt Award.
Approach the Falco like you were courting a beautiful lady, slowly, and with mounting anticipation of the pleasure to come. Take in the sleek bend of the fin to the fuselage and on along to the nose; appreciate the altogether rightness of the proportions of the design. When did you last see a Lycoming so tightly and beautifully cowled, like a long, slim leg encased in the finest nylon stockings? The stubby, tapered and glass-like wings projecting only about 11 feet from either side seem too small for their job, but are in perfect proportion to the rest of the aircraft. The whole impression is one of promised speed, crisp handling, and overall beauty. Now move closer.
Stand on the port wingwalk. Explore her more intimately.
Slide back the snugly fitting, 180° all-round vision canopy. It moves as smoothly as any factory job. Look around inside the cockpit. Smell the leather and new paint. Settle into the very comfortable seat, and let your feet relax on the carpet, fitting perfectly into the rudder pedals. Study the layout of the panel. Almost everything you need for IFR flight is present and falls easily to hand or eye. The finish, and the panel layout, communicates a feeling of professionalism and craftsmanship.
Two beautifully curved control sticks, with push-to-talk buttons, project up from leather gaiters on the floor. They move as if made from oiled silk. In the full aft position, each travels in a wide slot in its respective seat cushion. Mounted centrally at the base of the matt black panel is an engine control quadrant with three levers. This beauty has a constant-speed prop-not too common on a PFA homebuilt. Look further at the panel, and you'll see a little wheel poking out of the upper left-hand side. Retracting undercarriages are another complication not usually indulged in by homebuilders. There also an intriguing knob marked "ram air," as well as a complete set of annunciator lights along the top. The radio stack, switches and circuit breakers fall towards the right side as do a couple of engine health gauges.
Starting is very easily accomplished, simply a case-the engine was warm-of turning the ignition key, as for a motor car, and the whole aircraft comes to life. Gauges dance, gyros erect, radios fizz into life, lights come on. Slide the canopy shut and latch it. G-BYLL doesn't rattle, smell or vibrate. It hums politely through the sound deadening. But then, wouldn't you be disappointed to find your sophisticated lady had false teeth, halitosis or spots, once things begin to get interesting? Only the left-hand set of rudder pedals have toe brakes and taxiing the Falco rather reminded me of my very first few miles, at the tender age of 23, in a new V12 E-type Jaguar I'd borrowed for a weekend. You know the power is there. You can feel it. You just don't use it-yet. Steering through the rudder pedals is light and positive with little kickback over the taxiway joints.
At the holding point, put down 15° of flap. Roll onto the runway, push the noise-handle smo-o-o-thly forward and ... does it go! From brakes off to leaving the ground is a matter of only a few short seconds before lift-off occurs at 57 kts with the stick just aft of neutral and a degree of right boot applied. It is then necessary to set climb power and revs, bring up the flaps, establish positive rate of climb, un-dangle the Dunlops and peg the speed at 90 kts for best rate of climb, all in very short order. And, I'm sorry to admit, I was so busy during the first half-minute, I completely forgot to start my stopwatch, and don't know what the climb rate was-except that I very soon arrived at 3000', already discovering an aeroplane as light as a Lotus, as fast as a Ferrari, and as responsive as a racing car. I dialled up 2300 rpm with 23" of manifold pressure and "ram air" selected, let the aircraft settle down at a cruise of 125 kts and prepared to have fun!
Having explored the three primary axis controls for weight, harmonisation and effectiveness, the next thing to check was the stall. Clean, the Falco stalled at 59 kts with the stall warning horn blaring at 65, and a gentle nibble on the stick just before she broke, left wing down due to the uneven weight of me on one side. Two-up the Falco will let go either way, but you've got to be a bit of a dumbo not to know the stall is about to happen. The warning is excellent, and the recovery instantaneous with forward stick and power. I didn't try a spin, but I'm told they spin nicely and with standard recovery achieving rapid return to balance flight.
Gear and flaps down give a nose-down pitch, easily corrected on the large centrally-mounted trim wheel, and the stall occurred at 51 kts. Bear in mind, though, that I was nowhere near the max gross for my flight. I cycled the gear again to find it moves quickly, taking only 7 seconds to drop and 8 to retract. In the event of an electrical failure, there is a fibreglass cover just aft of the trim wheel allowing access to a small hinged crank, enabling manual undercarriage retraction or extension. Although the annunciator lights show the gear "up", "in transit" and "down", there are also two small drawing pin-shaped mechanical indicators which pop up into the slipstream above the wheel-wells (for the main wheels) and an indicator rod just forward of the firewall (for the noseleg). Very comforting.
Having established when and how G-BYLL was going to bite (I tried several stalls, both straight and level and in turns, and discovered no major surprises), I then set up a rendezvous with the camera ship, and settled down to some serious-and close-formation flying. It is this exercise which, more than any other, shows up any deficiencies in the control harmonisation and general ease of flying of an aeroplane. In something with slow control and throttle responses, the stick must be waved around the cockpit like an oversized gear-lever, whilst the throttle goes from full power to idle and back again, often several times a minute as you try to keep everything in the same place relative to the camera ship. In calm conditions, it can be difficult. In turbulence in a badly coordinated, poorly-handling aeroplane, it can be damn nigh impossible. In a Falco, it's like taking a walk in the park.
Nothing I have ever flown handles like a Falco. Having previously flown a production version, and the larger (and surprisingly, even more responsive) big brother, the F.14 Nibbio, I was not totally unprepared for G-BYLL. But if all you have every "driven" is a "spamcan" with soggy American control responses, the improvement is like getting out of a Morris Minor and into a Ferrari sports car. And I use the comparison deliberately. Just look at the pictures of the machine in the air, gear up. It just looks so sleek and fighter-like. Alive. Fast-moving. Able to be placed within inches of where you want. It is just like driving that Italian classic supercar at speed on a deserted road or closed circuit, able to clip apexes within fractions or effortlessly hold angles of drift out of corners to within parts of a degree with the throttle.
The ailerons are incredibly responsive. The stick can be moved-even during aerobatics-with the finger and thumb, transmitting the feel of the airflow to the pilot. The elevators are light, effective, and equally responsive. The rudder isn't just the usual tacked-on appendage for crosswinds. It needs just the slightest pressure to ensure perfectly balanced turns, even at the steepest angles of bank. The engine answers the smallest throttle movement at any speed, and the whole aeroplane is as near-perfect as any you're ever likely to fly-anywhere. It is almost like piloting a tiny jet. The Falco is cleared for the basic aerobatics and, as neither Ray nor Neville has had any training in much maneuvers, they were happy that I should "wring out" their creation. After the photo sortie, I did.
Loops are nice, starting at about 160 kts and requiring just the right amount of pull to end up inverted with sufficient inertia to come down the back side without approaching Vne or pulling excessive "g". Rolls, either to the left or the right, are very rapid-I started with a slight diving entry to gain speed to 135 kts, pulling up gently and just letting her roll about a point with almost no need for forward checking and negative "g". Satisfied with those, I settled for a few more exuberant wing-overs and chandelles before returning to Bourn's empty circuit. Overhead at 1500', I demonstrated two more loops and finished off with a couple of victory rolls for the benefit of Ray and Neville, who were waiting patiently on the ground for me to return their "baby".
In the circuit, the slippery Falco needs a degree of forward planning. Flap-limiting speed is only 95 kts, but the gear can be extended at 105 kts, giving a degree of drag before 20° of flap can be put down. As the speed bleeds off, full flap is called for at about 90 kts. Thereafter, she flies down the slope as if on rails. You hardly need a whisker of trim change, and I flew finals at just under 90 kts coming back to 80 over the hedge with a trickle of power to cushion the sink rate, she touched down at 75 kts. With practice, I could probably have done it more slowly, depending on conditions-which were just right on that day. The nosewheel can be supported with aft stick-on a grass field such action is essential-and brakes if required can be applied hard without worry.
Ray routinely operates G-BYLL out of a 500 metre grass strip up in Yorkshire, so her short-field performance is good. I tried one more takeoff from a standing start and "guesstimate" the roll took no more than a couple of hundred metres of dry tarmac. With gear-up and flaps-up immediately she was airborne, she climbed away steeply and obstacle clearance would be no problem. A short-field landing, approaching at under 85 with a smidgen of power, she could be down and stopped in comfortably less than 400 metres. As I discovered at altitude, aileron control is effective right down the speed range, too, and she's "pointy" enough to have good gust penetration in turbulent conditions.
Taxiing back, I was almost tempted to turn around and go off again for another hour! A Falco does that to you. Even your first landing will turn into a roller. After all, how can you let such a gorgeous, responsive and thoroughly sexy lady-sorry aeroplane-go without attention for very long? To those PFAers who are building one: keep at it, you guys. You're in for an absolute orgy of flying pleasure when it's finished. Oh, and if you're looking for someone to do the initial test flying....?
The Sequoia Falco-it's the sexiest looking, nicest-flying homebuilt aeroplane around!
(My word-processor apparently agrees with me. Running the spellchecker after completing this article it balked at the name Falco offering me phallic instead. Who says computers aren't intelligent?)