FI156 Fieseler Storch“…I have seen one ﬂying against views drawing, buying some from leading edge, the ﬂaps and aileronsthe wind backwards…” the www.bobsairdoc.com website, showing precisely the hinge points,“…the one of Mr. such and such but among the three or four three in addition to the test results in thewas coming straight down verti- view drawings that I received from wind tunnel.cally, nose diving, one meter from the USA there were not two alike. I had noticed some intriguing detailsthe ground and then landed in two I decided to stick to the most of the fuselage steel structuremeter stretch…” realistic one. Still on the internet on which fascinated me. I then began the site to “nurture” the project.I had heard many stories on the www.hinkleymall.com/storch.html I was pondering on how to solveFieseler Storch, but i had never , i purchased for $ 40 (you don’t this or that detail, trying always toseen one, other than in world war go broke just gambling) a big book ﬁnd solutions that were as close astwo old movies or in books and containing more than 200 copies of possible to the original one, but themagazines. original drawings from the Fieseler picture that kept coming back toBeing a lover of the slow ﬂying , of factory. my mind was the steel structure ofthe very slow landings, I got hooked Most of them were elevation views the fuselage. I started to evaluate ifby listening to the many legends of as built details, not too useful it was possible to build the fuse-about it and became for me impera- for the project, even though inte- lage like the one of the full scaletive to build one. resting. However were included airplane, some time before I hadI therefore started to get acquain- very precious drawings of the wing found small tubes in stainless steelted so as to have a good three original airfoil, with the slats on the in various diameter size , thick only
2,5 tens of millimiter. of Milano (www.castiglioni-tubi.it) . sq.dm of wing area.After some calculation i was The stuff arrived right before the A true beast! Just for precaution,amazed: a ¼ scale fuselage over Christmas holidays during which I before moving on, I measured out2mt. long would have weighted a started to work. the car and calculated that by re-little over one and half kilogram. I moving the stabilizer probably wascould not believe it. I recalculate but The project going to ﬁt.the result was the same. So i said I designed the fuselage on the“same as the full scale or nothing!” After scanning the 3 view drawings computer pointing out preciselyand I decided to start. One hand on i began to simulate variuos scales the welding spots of the structure ,my hearth and one on the wallet, I on the computer and i decided to marking them with reference to anordered over 40mt. of small tubes go with the 1/4 scale. The model horizontal line on the laying plan,in different sizes,worth about Euro that came out had a wingspan of and a vertical line to the ﬁrewall (ﬁg.300, to the company Castiglioni 354cm, length 242 cm and 175 1) Fig.1
By doing this i realized how fun-ctional was the original project.Basically the airplane is built usingstraight tubes, often parallel or per-pendicular with each other, resultingin an brilliant use of the space andthe structural functionality. Whoeverdesigned this airplane was endowedwith a great rationality.I postponed the rest of the project,until after the construction of thefuselage. I was not trusting yetmy calculation of the weight and,mainly, I wanted to touch with handthe strength of the structure, aboutwhich (considering the estimatedlightness) I had some doubt.The fuselage became very robust. rything in steel welded, the weight Basically i had no dead times, the went up to just 1800 grams.Without any jig o 1/1 scale dra- weldings (see picture above), once I used chromemolibden steel tubewing to use , i started to weld the i got the hang of it, became easy with different diameters to build thetubes with each other. It may sound and fast to do. I was feeling a landing gear. I had purchased thesestrange, but the structure was special pleasure seeing the silver tubes years ago’ from a vendor ofvery simple and , after paying lot alloy ﬂowing through the points of aeronautical materials. It’s the sameof attention to the alignment of the junction. material that is used to build realﬁrst weldings, the work was getting I ﬁnished the mainframe in three fuselage, such as the one of theeasier and easier as I was adding days of hard work: the scale tipped Piper Cub.more tubes and the reference at 1200 grams. After having added I used the same tube for the motorpoints were increasing. the shock absorbing landing gear, mount. The landing gear worksIt’s incredible how fast is this way the motor mount with a tubes exactly like the real one and fea-of building. As I was adding the structure too, all the connections, tures a very long stroke, springbracing tubes and the secondary the system to adjust the stabilizer loaded and cushioned with cylindri-spars the fuselage was getting incidence, the shock absorbing tail cal dumpers made of rubber likemore unwarpable and once ﬁnished wheel,the opening door, etc., eve- material at the end point. In the
end I handed the fuselage to my also the counterweights for the Fig. 2friend Perfetto (modeller and car static balance made out of vac-ubody repairer), who sprayed it with formed PVC.a layer of primer. Looking at it with I built on the ailerons working trims:that ochre colour looked like the I don’t know if they are beneﬁcial tofuselage of a real plane. the ﬂight , but they look very good.The engine cowl is made out of The main spars are made of spruce.aluminum from lithoplate and the The most difﬁcult part has beenfront is in ﬁberglass stratiﬁed into building the slats. Since I wanteda vac-u formed mould. I often use to match the original contour thatthis method to make detailed parts featured extra thin trailing edges,in ﬁberglass, it’s pretty quick. After I decided that the best way wasmaking a wooden mock-up, better to make a die and make them in ﬁberglass. Easier said than done. I built a die in two halves with spars and negative ribs on which I glued a 1mm bent PVC sheet. (Fig. 2) mad , but strong from the gained After several wrong shapes re- experience, i did it all over again sulting in weird agglomeration of and ﬁnally i had two slats more than ﬁberglass that ﬁlled the garbage satisfactory. Who knows, maybe can, i ﬁnally made a decent slat, using this system you can even but i realized that the proﬁle chosen build wings made out of ﬁberglass. was the wrong one! I had mixed up I put two heavy duty servos on each on the computer using a tempora- side of the wing, one for the ﬂap ry proﬁle , not the ﬁnal one…. It and one for the aileron. The wing happens. After the usual getting is hinged to the fuselage with pins,if a MDF panel is used (it does nothave veins that would show ), I useit as a matrix to make a 2mm PVCvac-u formed front end piece. Thevac-u forming system is the sameused to make the clear canopies. Ithen use the PVC piece as a mouldfor the ﬁberglass. You can alsomount on the airplane the PVCpiece, but ﬁberglass is stronger andlast longer.The wingConsidering how light the fuselagewas , I did not care too much aboutthe weight of the wing. The ribs(ﬁg. 3) are made of 4mm lightenedpoplar plywood, drawn on the com-puter and cut with the CNC Step4(www.step-four.at) pantograph.Still with the pantograph I made theﬂaps and ailerons hinges with 2mmﬁbreglass sheet , these included
Fig. 3and it’s kept in position with two servo connected to a stiff carbon iron and I achieved a ﬂawless glu-struts made out of 10 mm diameter pushrod which drives a steel levers ing. I did not encounter any problemaluminum tube, 1mm tick bought at mechanism; the rudder is driven by also because the fuselage of thethe hardware store. The ends are a giant scale servo and a pull-pull Storch is square and very simple.threaded so that can be adjusted cable system. While I was covering the fuselageindividually to control the aligne- it came to my mind the fuselage ofment of the wing. The rods tubes a Piper Cub that I had seen beingare covered with balsa aerodynami- restored at an aircraft repair shop…cally shaped. In the end I covered dimensions aside it was identical.the rods with a heatshrinkable tube I had more and more the feeling of(electrical type) which adhered working on a real plane. The canopyprecisely to the contour making it is made of 1mm PVC screwed toready for painting. I used the same little plates welded to the fuselagesystem for the struts of the landing and the frames are made of alumi-gear. num attached with 1,5mm rivets. It makes a great impression. I paintedThe Tail surface the airplane with nitro colours paint, including symbols and writings. AtAlso in this case i used poplar the end I sprayed a layer of mattplywood ribs, but unlikely the wing Fig. 4 clear cote, but ﬁrst I aged the planeI used special single spars: I built a rubbing it with extra ﬁne grain san-die (Fig 4) from aluminum sections dpaper to wear off the paint in theand I inserted a 10x10mm light points of major wear. Coveringbalsa spar, soaked in an epoxyresin, covered with a carbon ﬁber The entire model is covered withsox. This way you get a very strong Solartex green olive colour, I havespar, especially resistant to tor- chosen this colour so I was alreadysion. This system allows to make getting the interior of the right co-a warp resistant tail surface. As I lour. I went with the typical methodmentioned, the tail surface inciden- for the wing, while for the fuselagece is adjustable on the ground by I tacked the fabric with the heatmeans of a screw located under the sealing iron and, after laying a CAfuselage (picture on the right). The string on the tubes, I wrapped theelevator is driven by a giant scale fabric around, going over with the
The EngineAfter I have been looking for anEnya 240 V, 4 stroke V twin engine,in vain , it’s not produced for themoment, I purchased on the internet(www.laserengines.com) a Laser300 engine, 90° twin , 4stroke,50cc.The Laser engines are used bymany scale modelers among whichwe ﬁnd the world champions MaxMerchenschlager, Pete McDermott After some adjustments, the overalland Mick Reeves. package was very reliable and theThe Laser 300 seems to be de- sound , especially at the low end, issigned right for this model: it ﬁts fascinating.perfectly within the cowl and, The ﬁnished model wheighs 11,5looking from the air intake opening, kilos, the wing load is just 65 gr/resembles the Argus A10 that was sq.dm.: I could have had my dogused on the full scale airplane. Pino ﬂy in it, but I could not convin-I mounted it on the motor mount ce him.structure making some vibrations Jokes aside, i think this is thedumpers of rubber compound; I best way of building and the mostalso installed an on board battery satisfactory that i have ever usedfor the glow plugs. The battery gets in more than thirty years. Of courseactivated by the throttle pushrod the cost of the material (tubes, sil-when the engine is on idle (picture ver welding etc.) is substantial, butabove). I used some stainless steel I think that if I had built a model ofcorrugated gas pipe, bought at this size using conventional mate-the hardware store, to connect the rials it would not have been muchexhausts to the engine heads. cheaper.
Many beautiful airplanes have the fu- panick attack, I handed the transmit- reacts to all the controls, to makeselage made with a steel structure ter to him to land the model that it stall you have to really commitand can be built using this method, was ﬂying great. After that I started yourself.therefore I believe that soon I will to have fun. The model looks good, Needless to say that with suchhave back the welding pipe in my the ﬂight is hundred times better. qualities landings are a breeze,hand. It takes off in three, four meters, especially when you see the long goes up like if it’s on a ramp, nose sweet stroke of the shock absor-The maiden ﬂight unfolded as per diving with the ﬂaps down is very bers on the very tall landing gearusual routine: shaking knees, loose slow, it’s difﬁcult to believe it’s not that makes the plane look like a bigstomack, imminent heart attack… hanging on to a rope. stork…. maybe not all those that Iluckily Michele (great thumb) was on It’s very controllable at any speed, heard were stories.the ﬁeld and so,since I was having a even when it looks almost stand still www.paoloseverin.it