FTFC19 - April Showers by FoamyDM, Savoia Marchetti S55X (Porco Rosso)


Building Fool-Flying Noob
For the FTFC19 April Showers Challenge I will submit one From Scratch build that is in my idea folder:
Savioa Marchetti, SM-55 depicted in Porco Rosso

This was a real plane. First as a military vehicle then turned into a commercial endeavor.


This has been done in Balsa Before, and as part of the FTFC20 Classic to Modern design Build Challenge, I will turn this into a foam kit:

Project Ambitions: Design and build this plane, flying it, then make is watertight and Fly it in the rain. (as part of the FTFC19 April Showers Challenge)
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Building Fool-Flying Noob
Entered the contest and developed a quick plan to work on next week.

Version B2.0 of the plans... a little more refined, with some marks for alignment added.
I have the plane build successfully, ready for a maiden flight - Here are the plan updates


  • SM55X.pdf
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Building Fool-Flying Noob
yup it's all Twinsies (technically its a 5-some)
@kilroy07 already started.
@rockyboy - Thanks!
In Porco Rosso, there were like a fleet. (briefly) I'll have to pull out the VHS and watch it again...


Building Fool-Flying Noob
I managed to get some cutting done.
IMG_20190409_013432919.jpg IMG_20190409_013731045.jpg

I pulled the paper off sections that need to curl.
IMG_20190409_014054547.jpg IMG_20190409_013932880.jpg

More tonight... But this is what it it heading towards.


Building Fool-Flying Noob
Pulled out the ironing board before work, and took a moment.
Ironing the Bottom section
Top wing all set. While the line is perfectly straight, it will be on the inside and will be unseen.
Leaving the paper on helps keep melted foam off the iron. you can see that it will occasionally bubble.

I should be able to do some wing and engine pod assembly tonight. If I really get cookin' - there will be pontoons too!
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Legendary member
I’m out of town this week (again) any building I get done has come after the honeydo list. 😫

Hopefully get plans sorted this weekend though.


Building Fool-Flying Noob
Made some more headway tonight. I can't go too much farther. I have to waterproof the electronics, now...
At least the servos.
IMG_20190409_231352747.jpg IMG_20190409_232833757.jpg
The pontoon where more shoehorn than easy fit. Not my plan.


Building Fool-Flying Noob
I found an Italian Site - Thank you Google translate - that has a number of other great pictures, and details on the craft and it's service history in WWII.
and Outerzone has an RC model Drawing.


(Relative to S.55 of CRDA production and Macchi with very wide hulls)

motor: Isotta Fraschini “Asso” 500 RI
unit power: 510 cv on the ground
wingspan: 24 m
length: 16.750 m
height: m 5.00
wing area: m 2 93.00
empty weight: 5.150 kg
maximum weight: 7.450 kg
maximum speed: km / h 190
rise time: 25 'to 2.000 m
autonomy: 1.815 km

armament: 4 Lewis 7.7 mm machine guns

war load: 1,000 kg

designer: Alessandro Marchetti
test pilot: Alessandro Passaleva
first flight of the prototype: MM. 18, nc. 1000 in August 1924


SIAI S.55 II series (MM. 40253 - 40277) 193 in Squadron (87th Group BM) Pola 1929


(Relative to S.55 of CRDA production and Macchi with very wide hulls)

General : twin-engine seaplane of wooden construction, suitable for bombing.

Single-cell cell , with thick, concave concave profile, divided into three elements with an independent structure that is easy to assemble. Central plane limited in length to the distance of the outer walls of the two hulls attached to it connected to the two semi-wings with a strong transverse "V". Structure of the central floor and of the half-wings consisting of three wooden spars connected by ribs in plywood, with an internal plywood lining, forming a very resistant double-body structure and a series of cells constituting just as many compartments, such as to ensure, in case of necessity, the buoyancy of the whole aircraft. Double "T" spars, with plywood core and spruce currents.

Full ribs part and part composed only by the bridles built in plywood suitably reinforced by poplar ribs.

Central surface covering in canvas and painted plywood, except for the fabric-covered exit edge. Semiali covered in canvas and painted plywood on the leading edge and in the space between the side members, in canvas between the leading edge and the first longitudinal member and between the third longitudinal member and the trailing edge.

Hullsin wood connected to the lower part of the central wing plan, with a concave bottom in correspondence to the redan, slightly keeled in the bow and totally in the stern. Hull framing consisting of poplar and spruce frames, connected by ash spars and spruce currents. Connections of the elements making up the frames in ash and plywood. From the ordinate forming the redan part, towards the bow, a walnut and plywood gutter, connected to the floorboards by means of special hardware. Walnut bow wheel. Plating of the double bottom consisting of a layer of plywood and one of cedar blades arranged longitudinally. Between the two bands, two canvases and three layers of antiputrid and impermeable mastic are interposed. Planks of side and plywood deck. Walled blankets up to the waterline at the

Live work varnished with two coats of black antiputrida hydro-spinning varnish, one of special stucco and three of black varnish. Paint and stucco are waterproof.

Dead work varnished with five coats of glue, stuccoed and lined and then painted again with five coats of transparent adhesive varnish and two of aluminized glue varnish.

RT installations at the bow of the left hull, between the tanks and the place of the machine gun, transmitter A 350 and receiver AR4 (which allow transmission on long and medium and short wave in telephony and telegraphy, both with leaning plane and with fixed plane), a accumulator battery 12 V 39A (h), an anodic battery 180 V-1.5 A (h) and a tambourine for the spun plane. Complete the RT cabin with a tip-up seat and a sliding table.

Makeshift antenna for the transmission with the airplane in the sea composed of 2 planes that starting from the fixed tail plane go to the extremity of the wings, connected between them in correspondence of the fixed plane by a third plane from which the driver arrives to the RT installation in the hull. Power supply of the makeshift radio system consisting of a RA 350 generator coupled with the Garelli motor-compressor, both installed on the motor casing in the central part.

Cockpit in the central floor, front of the first longitudinal member, equipped with two wooden seats, with aluminum backrests designed to hold the "Salvator B" parachute, and a double command. On the floor, on the sides of the seats, two trapdoors to allow the launch with the parachute.

Engineer cabin in the central wing plan, between the second and third side member, with all the accessories related to the service and engine control. A hatch, located in the dorsal part of the central plane, allows access to the engines.

Double control composed of a duralumin lever that drives the depth rudder through extra-flexible steel cables that run along the inner side of the upper tail beams. On the upper lateral end of the T-lever are mounted the two handwheels connected together by a chain, operating the ailerons through an extra-flexible cable that runs outside along the back of the wing and returns inside the wing itself. Control of steering rudders operated by a pair of steel tube pedals and extra-flexible steel cables that also run outside the upper tail beam on the inner side.

Aerodynamically compensated ailerons at the end of each half-wing, with a welded steel tube structure and coated canvas.

Flecks supported by two tail beams each composed of two longitudinal members made up of four longitudinal elements in silver spruce, connected to each other by plywood diaphragms and covered with canvas and painted plywood.

Horizontal fletching formed by spruce spars, poplar and spruce ribs, steel struts and crosspieces covered in painted fabric.

Depth rudder in tube and steel sheet welded to the autogenous and covered with painted cloth, between the two vertical drifts and the three steering rudders, the central one equipped with aerodynamic compensation. Incidence of the variable horizontal fixed plane in flight.

Motors Isotta Fraschini Asso 500 Ri - 12 cylinders, with normal ground power of 510 hp at 1,975 rpm.

Walnut wood propellers : front, two-blade traction with fixed pitch, right-hand, diameter m. 3.6. Rear, four-speed propulsion with fixed pitch, right-handed, diameter m. 3.15.

Honeycomb water cooler fixed to the front of the engine casing with brass sheet outer coating and rear splitters. From the radiator, the water is sucked through copper pipes from the centrifugal pump placed under the engine crankcase. Spare water tank installed inside the central wing plane above the left hull.

Fuel in seven duralumin tanks, installed in both hulls (four in the right, three in the left), with a capacity of 330 l each, for a total of 2500 l. A cylindrical collector tank of 95 l capacity is also installed in each hull. Powered by "Lamblin" mechanical pumpsmounted on the motors.

Oil in four tanks: two main with a capacity of 28 l each, placed side-by-side on the engine stand between the two engines, fitted with cooling fins on the lower part. Two auxiliaries, with a capacity of 60 l each, pump for the supply of the main tanks in the central wing plan.

Garelli motor-driven compressor, coupled with the RA 350 generator in the central part of the stand, between the two motors.

Electrical system served by an accumulator battery installed inside the IT cabin on the left hull, external walled. Garelli 600 W light generator with base and reel, placed on the central plane, front left side. The system supplies power to various lighting outlets, installed in the fuel tank compartments of the two hulls and in the engine compartment; to the bulbs on the dashboard, in the FT cabin, in the engineer's room; to the lights: of float, of red and green way, of white tail, of anchor and to the bulbs for the lighting of the hull.

OMI camera , with plates and film 13 x 18, with a 300 mm focal length lens placed vertically between the false front spar and the first spar of the left wing. A door located on the back of the wing allows access to the machine, while in the extrados, in correspondence with the objective there is a door whose opening is controlled by the left hull by means of a rigid rod. On the back of the wing, on a special support, there is a reel that sets in motion by means of a flexible mechanical transmission the clockwork mechanism of the auto-chronometer which, by means of a similar transmission, operates the camera. When the operation of the machine is not affected, the reel can be stopped.

Fire alarm on the dashboard together with the buttons operating two "knock-out" type fire extinguishersthat send the liquid under pressure to the carburettors. Two 1 l fire extinguishers in the cockpit mounted on the first side member, one on the right and one on the left.

Launch rockets installed near the right pilot's seat and in front of it, under the cover, support for a rocket. At the machine-gunners 4 boxes with 12 artifices each; 2 under the front loader hull of the left hull, one at the bow and one at the stern of the right hull.

"Hall" type anchor at the bow of the right hull on the deck, connected to the extreme bow, with a line rope of 18 mm of diameter and 30 m of length, from "Occhio di cubia" to a winch installed inside the hull.

Cleat and ring , respectively on the extreme bow and stern of each hull, in correspondence with the lower attachment of the transom.

Two rings for the trailer on the joining plates of the hulls to the first longitudinal beam of the central plane. At the two upper ends of the first and third side members of the central plane 4 rings for the suspension of the apparatus.

Brass pump with relative piping in each hull for draining bilge water.

Defensive equipment consisting of four Lewis cal.7,7 machine guns mounted on93 cmcompensated "Vickers" type swivel supports, one aft and one at the bow of each hull.
Ten magazines of 47 shots per weapon in special boxes.

Offensive equipment consisting of a bomb holder placed under the central wing plan at the three spars, with the following load combinations: a 800 kg bomb; two of 500; four of 250; eight of 100, the latter suspended by elastic steel bands.

Release control installed in the left hull. A special opening on the internal wall allows the observer to aim for the Jozza finish line. The opening can be closed using a celluloid door that slides horizontally along the hull through two guides. Hinged screen in front of the door that can be lifted when aiming.

I like this Paint Scheme of the wing:


I have redone the pontoons... maybe this will be better?


Building Fool-Flying Noob
I weighed the doped-up servos and they weight in at around 15-17g each.
I also cut an alignment slit in the wing base... And noticed the pontoons are different lengths. 😵

This disappointment led me to Sim the rest of the night.

This will likely not get built. By month end. 😩