The instrument panel arrangement is good, with engine gauges below the classic arrangement of flight instruments: airspeed indicator, attitude indicator, altimeter, turn coordinator, directional gyro and vertical speed indicator. The airspeed indicator is quite poor, with a minimum of speed indications, but it shows 80 knots for approach speed with the pointer up and the cruising speed of 160 knots with the pointer down.
We have a combination manifold pressure and fuel pressure indicator (which could be used as a fuel flow indicator), tachometer, voltmeter. Outside air temperature (OAT) and exhaust gas temperature (EGT) indicators complete the engine instruments. We also find a magnetic compass and a G-meter.
The avionics include a Bendix-King KX-125 nav-com, Trimble TNL 1000 GPS and a Garmin 100 GPS as a backup, along with a transponder.
Getting ready for departure I put my headphones on, and I have the unpleasant surprise to learn that, with the Nustrini canopy closed, we can hit our head on the Plexiglas (a sure problem in aerobatic flight!).
I appreciate the left (optional) throttle, and I realize that the control stick is too tall, forcing me to grasp it with my fingertips (index and thumb) below the stick grip. The injected Lycoming starts with the usual priming with the boost pump and full mixture. Visibility during taxi is good in spite of the nose-high attitude caused by the long nose gear. Steering with the rudder pedals is easy even with the pedals so close together. How much foot space should you demand for the privilege to fly a winged sculpture like the Falco?
Pre-takeoff check at 2,000 rpm, entering runway 07, neutral trim, 15° flaps. Lined up and throttle pushed softly forward, and we are on the takeoff run without too much right rudder needed.
At 45 knots I softly raise the nose. At 65 knots we rotate with a 10° positive pitch, and we allow the plane to further accelerate, retracting the gear at 80 knots followed by the flaps, with no need to re-trim the Falco. Setting manifold pressure to 25 inches at 2,500 rpm, this flying Ferrari holds 1,500 fpm on the VSI, at 90 knots. The nose of our aircraft, well above the horizon, suggests left and right turns in order to see what's ahead.
We level off at 5,000 ft enjoying the light, precise, and harmonious controls, which allow for the easiest formation flight with the Seneca, playing a bit with the throttle to position the plane according to our photographer's request. The front windshield bow is bent backwards, interfering with my view of the chase plane. The canopy, on the other hand, allows for a spectacular 360° visibility, and could use an anti-UV sunshield to increase comfort under a strong sunshine. When flying through turbulence, the Falco reacts firmly and easily maintains its trim, pretty much as an executive jet would.
After the photo shoot, we go on to the stability evaluations at altitudes between 4,000 and 5,000 ft. In pitching, we get positive static stability from the Falco, with slight decline under 80 knots, with a tendency towards neutrality. Dynamically, a phugoid oscillation (up-and-down roller-coaster-type oscillation) dissipates after four oscillations. In roll, the airplane is perfectly neutral; it stays at the imposed bank. In yaw, under dynamic inputs, the Falco behaves like an arrow: three quickly dissipating oscillations and that it it.
It is during maneuvering that our plane shines. The stick force gradient is quite light in pitch and roll, working in perfect harmony with the rudder pedals. The ailerons are light and precise, the elevator is a bit heavier, the rudder has a perfect relationship between a slight rudder pedal deflection and the yaw response. During turns, adverse yaw is well under control, and there is very little tendency to climb or descend during entry or recovery from turns.
This superb behavior is also found at 100-110 knots, and it is a delight during aerobatic maneuvering. Loops are initiated at 160 knots, with 100 knots on top. Aileron and barrel rolls between 125 and 140 knots. Sequencing maneuvers proves irresistible, reminding me of the french CAP-10B. The maximum rate of roll is around 120°/second when the rudder is used to help.
The Nustrini canopy, although beautiful, is a great nuisance: You hit your head on the Plexiglas at the first minor hints of negative Gs!
I now climb to 5,000 ft and, at and OAT of 30°C, we have a density altitude of 8,000 ft. I set the manifold pressure to 25 inches at 2,500 rpm, lean the mixture using the EGT to get 75% power. Our well-trimmed airplane, in straight and level flight, is held in the low-drag 'bucket' of our NACA laminar flow wings. I register 175 knots (324 km/h) average GPS speed during flight in opposite directions. Fuel consumption is 10 gal/h.
With a setting of 21" of MP at 2,400 rpm, the speed falls to 160 knots (296 km/h), burning only 9 gal/h. Under this setting, we can expect a range of 1,200 km (648 nm) in four hours of flight, with reserve.
The addition of full landing gear doors and other minor modifications to reduce parasite drag could result in a gain of about 10 more knots, as was my experience when flying two other Falcos (both with 160 hp) in Oshkosh.
At 70 knots, the Falco still shows good control response in all three axes. The stall with the airplane clean happens without warning at 57 knots. PP-ZMB has the tendency to drop her right wing, but recovery is immediate. In the dirty configuration with full flaps, the stall again comes without warning and dropping the right wing at 53 knots. I think this behavior could be due to the position of the stall strip on the right wing, and it could be corrected.
During a 2G turn and with considerable buffeting, the Falco shows this same tendency during an accelerated stall, but the recovery is almost immediate with minimum loss of altitude.
After some aerobatics, we begin our descent for landing. The low gear extension speed at 108 knots requires good planning to slow down before entering the traffic pattern. Trim adjustments are small after changes in configuration and power. This is good since the trim wheel is beyond reach with the aerobatic restraint belt tightened! The hand shuffling necessary to lower the landing gear is not a problem, since the Falco reacts benevolently with its almost neutral pitch stability.
Turn to base for runway 07, lowering a touch of flaps and maintaining between 80 and 90 knots; final approach stabilized with full flaps (45°), we get 80 knots by setting 15" of MP, holding the airspeed indicator pointer vertical and the climb at 500 fpm. Easy correction of a left crosswind, we cross the fence at 70 knots, flaring with a very nose-high attitude and the touchdown is just too gentle, very well handled by the excellent trailing link main gear. We taxi with an open canopy, park in front of the hangar and shut off the Lycoming with the mixture.
I sit there, silent, for a long time, meditating about this machine I just flew. I think of the fortuitous encounter with the hawk, and I smile when I realize that the F.8L is also a member of the Falconiform Order, Accipitridae Family, which includes the smallest of hawks to the majestic eagle.
Bravíssimo, Signore Frati!
Brazilian Fernando Almeida has been an admirer of Stelio Frati from an early age. He was not alone -- Almedia reports that during his training as an aeronautical engineer, one classmate spent his idle time sketching airplanes as he imaged Stelio Frati would design them. The student was José Kovacs, who later designed the Neiva T-25 Universal, a 300 hp military trainer which was used by the Brazilian Air Force for many years, and Kovacs based much of the overall design on the Falco. More recently Kovacs designed the Embraer T-27 Tucano, a superb 750 hp turboprop military trainer which has been sold to several air forces, including the RAF. Unlike the Universal, which bears a strong resemblence to the Falco, the Tucano is a fresh new design, but Almeida reports that one of Kovacs's design goals was to duplicate the harmonized control handling ot the Falco.
Fernando Almeida writes for aviation magazines and has served as a test pilot for a number of new designs. Among these was the 180-hp all-metal "Squalo," an attempt by a homebuilder to duplicate the Falco. Almeida reports that the stabilizer was too small, and the airplane was unstable in pitch. Fernando Almeida lives in São Paulo, Brazil, and his full-time job is at Volkswagen of Brazil. Trucks!