One original wooden part to MY-14

Torstai 1.6.2017 - Reino Myllymäki

Suomeksi

The VL Myrsky II restoration project has three steel-tube fuselage framework (MY-5, MY-9 & MY-14). They have lain on the ground below an open sky at least 20 years. Therefore wooden parts have decayed and steel parts have corroded. The project has got ready for substitute all wooden parts by reproduction ones.

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There is boarding step located below the rear side of the canopy in the left side of the fuselage. The boarding step has a small hatch in order to keep the fuselage streamlined when the step is not in use.

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The boarding steps of MY-5, MY-9 and MY-14 were all very corroded and the hinges of hatches were stuck. Luckily, one unused original spare part has been found in the storages of the Finnish Air Force Museum. One supporting tube was broken and there is a hole in an aluminium box.

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The steel structure, the hatch with hinges and the plywood frame have been taken from the unused spare. The lacking tube was taken from the step of MY-14. It was welded to the steel structure.

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The aluminum box was taken from the step of the MY-5. The metallic parts were blasted by glass balls and painted. The dented aluminium parts of the box and the hatch were corrected. The original screws of the plywood frame and box were substituted by equivalent new screws.

It seems that MY-14 will have at least one original wooden part: the plywood frame of the boarding step.

Historical photo: The Finnish Aviation Museum. MY-9 photo: Reino Myllymäki. Other photos: The Finnish Air Force Museum.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14 got more equipment

Keskiviikko 24.5.2017 - Reino Myllymäki

Suomeksi

There is a metallic map box on the left hand side of the cockipit of the VL Myrsky II.  Luckily we have an original part. The proper box is in a good condition but a little crooked and the leather strap was in poor condition.

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The map box was blasted by glass balls, straightened, primed by Isotrol lacquer and painted to colour tone Ral 7045 (gray). The leather strap was renewed but the popper is original. The strap was riveted to the box. The box was fixed by renews bolts and screws to the cockpit.

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There is a fresh air lever on the right side of the cockpit. The original was in a very poor condition. Luckily a quite complete original part was found from the storages of the Finnish Air Force Museum. Only the another fastening band was lacking.

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The fresh air lever was blasted and painted. The help texts were renewed, too. The lacking fastening band was substituted by a repaired original part. The wire of the lever will be installed later.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

VL Myrsky has crank starter

Torstai 18.5.2017 - Reino Myllymäki

Suomeksi

The Twin Wasp engine of the VL Myrsky II is started by an inertial starter. Normally, the starter is powered by an electric motor. When the starter has enough revs, the pilot pull the starter on and the engine will - hopefully - start.

But the revs can be made by a crank starter, too. The extension rod of the crank starter is located to right side of the aircraft near the leading edge of the wing.

The location of the joint of the extension rod and the crank starter handle is not easy to find in the photos. Most of the photos present the left side of the aircraft. And the camouflage painting is dark just there.

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Left photo: Finnish Air Force Museum, right: Finnish Aviation Museum.

When the aircraft has not coverings, the location is easier to find. The joint is supported by three tubes from three direction. The crank starter handle is located in the cockpit. It has place on the left side at the back of the tail wheel switch.

The crank starter handle of the MY-14 has disappeared as well as MY-5´s and MY-9´s. The brackets have been spared. Luckily, an original crank starter handle of the VL Myrsky has been found from the storages of the Finnish Air Force Museum. Only cleaning was needed.

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MY-14 got brackets from the MY-5 since they were in better condition. They were disassembled, blasted, painted and fixed. After that, the crank starter handle found an appropriate place.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Emergency equipments to MY-14

Maanantai 15.5.2017 - Reino Myllymäki

Suomeksi

VL Myrsky has the emergency equipment consist of a pairs of skiis, an axe, a K-ration pack and a toolkit. They are located after the cockpit and the oxygen bottles below the the canopy aft glazing. They were attached to the plywood plate by leather straps. The access to the emergency equipment bay was arranged by the glazing hatch.

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The brackets of the plywood plate were existing in the all frames (MY-5, -9 and -14). Although the axe did not belong to the emergency equipment anymore, it had still the leather straps. Now the straps were disappeared except small parts between the plywood plate and mounting plates. All emergency equipments were disappeared.

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The new plywood plate has been made according to the drawings. The brackets were blasted and painted. The screws were renewed.

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The mounting plates of the leather straps were renewed. The leather straps were made according to the drawings and the preserved parts of the Fokker D.XXI (FR-137).

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The leather straps were fixed to the plywood plate according to the drawings.

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The pairs of skiis were restored and tared earlier. They were fixed to the plate. The axe was fixed tentatively since the axe and the toolkit did not belong to the emergency equipments during the wartime. The K-ration pack belonged but it has disappeared. The drawings of the K-ration pack were disappeared, too.

The K-ration pack can be redone if the needed drawing will be found.

The historical photo: The photo archive of the Finnish Aviation Museum. Other photos: The Finnish Air Force Museum.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Wheel-bay cover fastening ring for VL Myrsky II

Lauantai 18.3.2017 - Member of Tuesday Club

Suomeksi

The landing-gear of the Myrsky retracts towards the fuselage with the struts and wheels retracting into bays between the main spars in the roots of the single, continuous wing.

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On the top-side of the wing the wheel-bays are covered with slightly domed covers made of aluminium-plate. The covers are fastened with screws to a plywood ring forming the wheel-bay. Most of the wheel-bays, including their aluminium cover-plates remain hidden under the mid-fuselage covering the centre-part of the single wing, but a part of them are covered by streamlining-plates at the wing/fuselage joints.

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The aluminium-plate wheel-bay covers have already been made and now the making of the three needed cover-fastening rings are underway. One is needed for the test-assembly wing and two for the final wing that will be made for the MY-14.

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The making of the fastening-rings begun by making a mould. As on the drawings, a circle with a diameter of 750 mm was drawn onto a strong wooden board. Then sturdy nail were nailed along the drawn line with a spacing of ca. 2 inches. The fastening-rings will now be made by laminating eight layers of 3 mm thick 30 mm high, long plywood strips against the nailed circle, thus forming a 25 mm thick fastening-ring.

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The first plywood-layer was tightened against the nails and onto it three more layers were glued using Erikeeper plus adhesive intended for outdoors use. The four layers were pressed tightly together using clamps. When the adhesive had dried properly, the clamps were released and the next four layer were added using the same procedure.

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When the adhesive had dried the fastening-ring was removed from the mould and finished. It was then planed into a triangular cross-section with a top width of 25 mm. The other two rings will be made in the same way.

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As the test-wing had been fitted into the assembly-jig and the part between the wing-spars had been assembled the test-fitting of the fastening-ring could be made. And it was a good fit. Also the aluminium cover-plate went into place nicely. The next step will be making and fitting the plywood landing-gear well walls in the wing.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

More than just building wing for VL Myrsky II

Lauantai 4.3.2017 - Member of Tuesday Club

Suomeksi

In the restauration of the VL Myrsky II (MY-14) the majority of the work done during the past couple of years has been on the wing. This might lead one to believe that the Tuesday Clubs part the whole project is only doing woodwork to make the wing. However, a lot of other types of work has also been done, as I have told you in earlier blog entries. This time I will cover some of the work on the following sub-assemblies; bomb-racks, the propeller-blade openings in the spinner and the landing-gear.

Originally the Myrsky-fighter was not equipped with bomb-racks, but in 1944 a bomb-rack for a 50-100 kg bomb was fitted under each wing. These racks were also suitable for drop-tanks. For these there was a connector to connect the drop-tank to the planes fuel-system.

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Fortunately parts for many racks have survived in the collections of various museums, so with some reconditioning done, we can fit the MY-14 with original racks. However, the racks found were partly disassembled, had broken parts, partly corroded or otherwise in need of reconditioning. So a selection of the best rack-parts were inspected, reconditioned and combined into complete racks to be fitted to the Myrsky´s wing in the Tuesday Club.

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The spinner for the Myrsky has cut-outs for each propeller-blade and its regulator mechanism. At the base of the spinner the cut-outs are open so that the spinner can be fitted over the propeller hub and around the propeller-blades and fastened to the spinner’s back-plate.

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On the spinner’s back-plate there is a protective sleeve made of aluminium that closes the back-part of the cut-out, thus creating a round cut-out hole and a closed back-edge on the spinner. No original sleeve has survived, so new ones have to be made. The missing spinner back-plate has already been made earlier in the Tuesday Club.

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The making of the sleeves begun by cutting blanks out of aluminium sheet, according to the drawings. Then they were test-fitted to the openings. A wooden mould was made for the making of the profiled, bent edge of the cover-plate, and then the blank was fastened to the mould and beaten into shape. We still have to drill the holes needed for fastening the cover-plates to back-plate and then the cover-plates can be fit into position. The finishing work on the cover-plates is now ongoing.

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No complete Myrsky landing-gear has survived to be fitted to the MY-14. Thus most of the landing –gear has to be made. Fortunately original wheels have survived and can in due time be fitted to our Myrsky. The reconditioning of their hubs and brakes has been covered in earlier Myrsky blog-entries.

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The Tuesday Club has neither the tools nor the skills necessary to make the needed new landing-gear oleo-struts. Patria, who is the major sponsor of the Myrsky restoration-project has taken the responsibility for getting them done. However, some landing-gear parts can be made by the Tuesday Club. Work on the landing-gear retraction-fork that connects to the oleo-strut is ongoing in the Tuesday Club. The hollow forks (one for each strut) consist of steel-ribs that are covered with steel-plates.

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The work on the fork was started by making a full-size model to plans. In addition to this a metal jig was made for the assembly of the final forks. The wooden model makes interpreting the drawings easier and without a jig, the necessary dimensional precision of the retraction-fork cannot be achieved.

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Work on the fork itself begun by cutting steel-plate blanks to measure to form the parts that will become the sides of the forks. Holes were drilled at both ends of the blanks after which they were bent to form and measure. Assembling the forks in the jig is ongoing.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14 got original medicine box

Torstai 16.2.2017 - Reino Myllymäki

Suomeksi

The medicine box of the VL Myrsky II fighter located outside of the cockpit in the rear fuselage. The box was behind a access panel in the left side of the fuselage.

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The access panel of the medicine box located below the cockipt rear windows. The location was shown by red cross sign. It was not in exactly right place since the access panel was located under the national insignia. Between the access panel of the medicine box and a entry foothold of the cockpit there was one bigger access panel.

The stand of the medicine box was manufactured from the metal plate by shop welding. The sides of the stand was lightened by holes. The box was fixed by leather straps. The straps were fixed to the stand by riveting.

An original stand was found. It was restored by cleaning and painting. The medicine box is a aircraft part standardised by the State Aircraft Factory. VL Pyry and VL Myrsky had same box. MY-14 got the medicine box from Pyry.

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The medicine box was complete except medicines. According to the index of the box, the box consisted of boracic ointment, morphine and aspirin and two bottles of camphor. None wartime pep pills were found and according to the index, pep pills did not belong to the content of the medicine box.

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When MY-14 will be ready the medicine box will be in hiding behind the access panel. Several other interesting details will be in hiding, too. However, a "Demo-Myrsky" is planned to be assembled from a test wing, the fuselage of MY-5 as well as from the extra original parts and newly produced parts. The demo will be covered partly by plywood and partly by perspex. How it will implemented and how the inside structures and detalis will be seen is not clear yet.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Assembling VL Myrsky (MY-14) test-wing in jig started.

Tiistai 14.2.2017 - Member of Tuesday Club

Suomeksi

The MY-14 project group decided to build a test-wing of ca. 2.5 m length, measured from the wing-root. This will be done to ensure that the fitting of equipment and fittings that are fastened to the wing spars, including drilling holes for necessary fasteners can be done properly and also to pinpoint possible flaws in the building of the wing.

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During the early weeks of this year we were able to finish the front- and rear spars of the test-wing as well as the drilled holes for the metal parts lead-throughs. Also all the wing-ribs have been finished. Thus, the test-assembling could be started. The assembly work of the test-wing, as well as that of the final wing, will be done in a precision jig. A separate jig was made for the assembly of the test-wing. Using this, we can make sure that the placement and alignment of the spars related to each other will be spot-on. This is a must for us to be able to assemble the wing in strict accordance to shape and measures of the drawings.

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The assembly of the test-wing was begun by fastening the front- and rear spars in the jig. After this some parts of the landing-gear actuating mechanism were fitted to the drilled-through. The next steps was to start fitting the enclosed wing-ribs in-between the spars.

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At this point the benefit of the test-assembling became evident, as problems showed that the drawings were partly insufficient. Not an earthquake of challenges, but some additional head-scratching was needed before work could continue on the test-wing.

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Now the wing-ribs between the spars are glued into their correct positions and the metal parts that attach to the wing-spars are fitted. Covering the top-side of the wing between the spars is ongoing. Assembling the leading- and trailing edges of the wing will start only after all internal structures between the spars have been made and installed.

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The test-wing will not be disassembled after the tests, but instead it will become a museum exhibit. It will be used to show the visitors the construction of the WW II Myrsky-fighters wooden wing. For this purpose the top-side of the test-wing will be partly plywood-covered and partly covered with a clear polycarbonate sheet. The inter-spar wing-ribs will be plywood-covered on one side with the other side covered with clear polycarbonate sheet to show their construction.

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Parallel to the work on the wing-spars for the test-wing, work on the spars for the final wing has moved forward. The front and rear parts of both wing-spars will soon be ready to be glued together so that they both form box-spars. As this wing will be made as a left and a right wing that will be bolted together with the joint strengthened with steel-plates, instead of the one-piece wing of the original Myrsky –fighter, holes for the assembly bolts must be drilled in the spars. Assembly work on the final wing will take place only after the test wing has been finished and properly tested.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14's tail repairs, part eight

Perjantai 10.2.2017 - Reino Myllymäki

Suomeksi

The chains and cables for rudder, elevator and aileron trims of MY-14 were lacking except some very rusty chain pieces. So, the chains and cabled had to be manufactured acoording to the designs and original parts.

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The used chain proved original material since the stamp was same than in orginal parts. The wire clips were original material used in the State Aircraft Factory but not exactly same.

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The feed-throughs were existed but abrasion covers were lacking. They were made from "lusto" according to the designs. "Lusto" is an old polymere, nitrocellulose, called also to Parkesine.

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The bearing bracket of the rudder trim and the traction wheel of the elevator trim were in the restorable condition. They were disassembled and repaired. The aluminium wire coils were lacking and the new ones were made by lathing.

All parts were assemled and the entity was tested. It is working!

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Work on the exhausts of MY-14 ongoing

Sunnuntai 29.1.2017 - Member of Tuesday Club

The original engine planned to be used on the VL Myrsky was the British Bristol Taurus. Because of WW II this did not happen. Instead, the American Pratt & Whitney R-1830 two-row radial engine was selected, almost the same version as on the Douglas DC-3.

Myrskyn MY-14 - entisöintiprojektia varten on käytössämme DC-3 koneessa ollut Twin Wasp -moottori. Koska moottori on ollut DC-3 koneessa, se ei ilman muutoksia sovi Myrskyyn asennetavaksi. Yksi merkittävä muutoksen kohde koskee moottorin pakoputkia.

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The Twin Wasp with the exhaust collector of DC-3 in left picture and the Twin Wasp of VL Myrsky II with oval pipes in right picture.

On the DC-3´s Twin Wasp the exhausts from each cylinder is connected to a single exhaust gas collector from which there is a single exit pipe. On the Myrsky a different solution was implemented – The exhaust from each cylinder was gathered to be expelled through five oval exhaust pipes on top of each other on both sides of the engine under the NACA cowling ending at the back-part of the cowling.

At the end of each 10 round exhaust pipes 200 mm long, tapered nozzles were welded. At the weld the nozzles had a diameter of 60 mm but they were tapered towards their end, ending as a 28mm X 60 mm rectangles. A smaller final cross-section was used to increase the speed of the exhaust gases and thus creating some added thrust.

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The exhaust system that is to be built during the restauration will be a copy of the original one. At the moment the single pipes from each cylinder, forming a veritable “snake-pit” are being formed into shape by a partner contractor at Samet Oy. The nozzles are being made by the Tuesday-Club.

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They are being made from 28 rectangular parts cut out from sheet-metal. To form them into the requires shape the club made the necessary male and female mould parts used to shape the flat sheet-metal parts In a hydraulic press.

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After being pressed the edges to be welded were cleaned and chamfered for welding. The assembly, welding and fitting of the exhaust-system to the Twin-Wasp engine will be done by Patria Oyj.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Oxygen system for MY-14

Perjantai 27.1.2017 - Reino Myllymäki

The oxygen bottles, controls, taps and meters of MY-9 and MY-14 were disappeared but the brackets, adapters, the remains of the oxygen pipes as well as the plate of the pressure and flow meters and controls were remaining. The original oxygen pipes were broken off and therefore they were useless.

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The oxygen bottles were found from the Hallinportti Aviation Museum and they have been in VL Myrsky fighter according to the imprints of fastening bands. The other parts of the oxygen system were found from the storages of the museums. Therefore it was possible to assemble the proper oxygen system of VL Myrsky fighter for MY-14 from original parts. Only the oxygen pipes had to be renewed.

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The best brackets were chosen in order to be restored. The steel and aluminium bands were blasted by glass balls and the bolts were renewed. The abrasion covers of the fastening bands were renewed. According to the design documents they should be made from leather. However, the imprints on the bottles showed that they were made from canvas fabric. Therefore canvas was used in the restoration.

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The bottles and the parts of the oxygen system were cleanded and covered by Renaissance wax. The pipes were made from new copper pipe and the fastening screws were renewed. Othewise the system was assembled from original parts. The normal solder paste was used in the solder joints instead of a hard solder.

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The fastening band of the rubber oxygen tube was taken from the MY-9. It was straightened, basted by glass balls, painted by Isotrol stripping laquer and paint finish. A padding made from leather was fastened inside of the band.

Photos: Finnish Air Force Museum.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14 got voltage regulator

Keskiviikko 25.1.2017 - Reino Myllymäki

Suomeksi

VL Myrsky II had a Russian voltage regulator located at the right corner in the front of the cockipit. However, the regulator of the MY-14 has disappeared. The brackets remained but they were corroded and bent. The sprung rubbers were destroyed and the filling sleeves were disappeared.

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A proper voltage regulator (RKK GS 1000) was fortunately found from the storages of the Finnis Air Force Museum. It was cleanded outside and inside and covered by Renaissance vax.

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The brackets were fixed, blasted by glass balls and painted. The bolts and sprung rubbers were renewed and the used rubbers were probably from MiG fighters. They seems to be copied from Britishs ones. Needed filling sleeves have been made from duraluminium by lathe work.

Photos: Finnish Air Force Museum.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14's tail repairs, part four

Lauantai 1.10.2016 - Reino Myllymäki

We had an almost intact VL Myrsky II’s tail wheel. The only missing part was axle and it was made at Air Force Museum from piece of solid 20mm steel tube.

Tail wheel rim is made from Elektron-metal which is a trademark for a range of magnesium alloys. Same goes for brake shields of main wheels. These parts were badly corroded and thus tiresome to dismantle. Paint was worn out and bearings stuck.

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Both outer and inner tires turned out to be useless. Obviously corroding of rim had eaten rubber at rims edge. Inner tire had been patched up several times (!) and was no more usable.

The rim was dismantled into parts and new holes were drilled into retaining ring of bearing for tool. Clogs of retaining ring were left as is. Rim halves and bolts were blasted with glass beads, primed with Isotrol Klarlack and finished with Isotrol color tone RAL 7005.

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Bearing was replaced with a SKF 6304 bearing with new mounting nuts. Tires were replaced with commercial 12 by 4 inch inner and outer tires. Air valve had to be lenghtened with a stub of brass tube soldered in place.

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Isn’t it good looking now!

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14's tail repairs, part three

Keskiviikko 28.9.2016 - Reino Myllymäki

Even after MY-9 empennage was attached into MY-14 fuselage frame, there remained things to fix at Tikkakoski.

Tail wheel assembly was missing support tubes and some existing ones were eaten by rust. They had to be renewed. Tubes coming in from fuselage corners were good up to the original joint but even they had to be straightened.

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Replacement tubes were taken from MY-9 as possible but also new tubing was used. Original tubes included wall thicknesses down to as thin as 0.5 mm, but all new ones were of 1 mm wall thickness. Axle bushings were made of new commercial quality tube.

Further there were things to fix at tail wheel assembly’s upper supports and attachments. All six pipes leading there were either missing, broken or twisted. Replacements were again found from MY-9, but bushings and supporting lugs for retracting mechanism had to be made from new material according to drawings.

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Again all needed welding was done with TIG welding, partly by Rauno Pylväläinen from Patria and partly by Antti Lappalainen from Finnish Air Force Museum.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14's tail repairs, part two

Sunnuntai 25.9.2016 - Reino Myllymäki

Tuesday Club’s Matti Patteri made an assembly jig for joining of MY-14 fuselage and MY-9 empennage. Joining was done at Finnish Air Force Museum in Tikkakoski. Damaged tubes were straightened and cut where necessary. New pipes were taken from MY-9 fuselage as needed.

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Assembly and straightening was made as close to drawings as possible. Pipes were bended with the help of welding torch to align them exactly right. Also supporting wedges made of laminated wood were helpful during alignment.

Tube to tube joints were strengthened with sleeves. Corner joints where tube endings were shaped remained without extra support, unless there were original support flanges.

Myrsky’s fuselage is a welded frame made of chrome-molybdenum alloy steel tubes. Welding method was gas welding with unalloyed wire. By the time when Myrsky series was built, arch welding was just making its first steps at the State Aircraft Factory. Here it was decided to use TIG welding, which was done by Rauno Pylväläinen from Patria.

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Welding was done in two phases. When the fuselage and tail assembly were fixed into jig, some points could not be welded. For those last remaining points the fuselage was moved into a rotating platform.

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After welding, the tubes were first coated with phosphoric acid, then primed with Isotrol Klarlack and finished with Isotrol color tone RAL 7005.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

MY-14's tail repairs, part one

Torstai 22.9.2016 - Reino Myllymäki

There was three VL Myrsky II fuselages available and the least damaged of them (MY-14) was chosen as the basis for renovation. The least damaged meant here something far from being intact. All three fuselages (MY-5, MY-9 and MY-14) had been damaged in crashes in front of tailplane. They all had been transported to Valmet Kuorevesi factory to be rebuilt but they ended after war as surplus at a gravel entrepreneur’s back lot in Jämsä.

The empennage of MY-14 is totally missing as it was crushed by MY-41 smashing into it at Pori Airport. Tail assembly for renovation was detached from MY-9’s fuselage.

While MY-9’s tail assembly was rusted all over, it was still sound enough to be sand blown. Inner core of tubing was actually well preserved and tubes contained even some of the original anti-corrosion oil.

After removing all parts which could be detached without cutting, the rest of assembly was cut from MY-9 fuselage at original welding seams. Then it was sent to be sand blown and primed at an automotive and industrial paint shop in Vantaa.

After receiving the tail assembly back to our workshop we went on by doing necessary welding to prepare assembly ready for new stabilizators, rudder and elevator. These were manufactured by Tuesday Club and Vocational College Varia. Some bearing brackets had to shifted because MY-9 had not been built according to drawings. Obviously jigs were not made before MT-14 was assembled. Tail assembly had to be modified to match those newly built parts which were made according to drawings. 

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Myrsky?s spinner got its attachment parts

Perjantai 17.6.2016 - Member of Tuesday Club

For restoration of VL Myrsky II, serial MY-14, we have the original spinner. But this spinner is empty inside and lacking all parts to attach it over propeller hub. Thus we needed to make front and rear bulkheads. Front bulkhead comes inside spinner and rear bulkhead comes behind propeller and is attached to spinner's rear edge.

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Propeller must be removed first to get rear bulkhead around propeller shaft. It is secured with a collar attached to propeller hub. With propeller installed, front bulkhead is attached to propeller hub. Spinner is now attached over hub to both bulkheads.

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Both bulkheads were spun from a metal sheet according to Myrsky’s blueprint. We made an adjustable mold for spinning. With an adjustable mold we could spin both bulkheads which have different diameters. Front bulkhead is naturally the smaller one.

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We made 3 inch lightening holes into rear bulkhead with a punch press. By using a suitable punch and die those holes got also nice strengthening flanges.

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Now we are at a point where we have bulkheads which are ready to be installed for spinner attachment.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

There should be footboards!

Tiistai 24.5.2016 - Reino Myllymäki

Suomeksi

There are two footboards on the floor of the cockpit of the VL Myrsky. The supporting structure of the footboard is made from birch plywood and pine strips and the sliding surface from aluminium sheet.

The aluminium parts of the footboards of the MY-14 were repairable. Only cleaning by oxalic acid and solvent washing agent was needed as well as protective handling by Isotrol lacquer.

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But the wooden parts were in poor condition and the design drawings were lacked. By collecting the footboards' wooden parts of three aircraft (MY-5, MY-9 and MY-14) it was possible to assemble an almost complete supporting structure. By using it as a model it was possible to rebuild two new footboards from plywood and strips.

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Finally, the footboards were painted by Isotrol paint. The color tone is RAL 7005. The aluminium sheets were fastened to the supporting structures by wood screws. No by original screws but fully equal.

Reino Myllymäki

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Fastening bands for MY-14

Tiistai 10.5.2016 - Reino Myllymäki

Suomeksi.

VL Myrsky has a lot of fastening bands used to fasten equipments and fuselage formers to the chrome-molybden-steel-tube frame. The fastening bands were made either from 1 mm thick steelblate by pressing or from pipe stumps by welding.

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The fastening bands were disassembled from the fuselage frames of MY-5, MY-9 and MY-14 at the Finnish Air Force Museum. The broken bolts were released and the twisted bands were straighten. Some bands have been fixed by welding. The condition of the bands was very variable. Some were almost ready after glass bead blasting but some were very corroded. There was original paint inside the bands.

Some fastening bands were found from the storages of the Finnish Air Force Museum and some were made by using original blanks of the State Aircraft Factory.

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The bands were cleaned by glass bead blasting and phosphoric acid disposal. The Isotrol Klarlack was painted by brush for priming and Isotrol RAL 7005 was painted by air brush for paint finish.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

Instruction panel of VL Myrsky under restoration

Perjantai 6.5.2016 - Reino Myllymäki

Suomeksi

Although a lot of VL Myrsky parts are lacking, the situation of the instruction panel is better. All missing meters were found. However, the instruction panel needed repair. The conservation team of the Finnish Air Force Museum focused on it.

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The instrument panel has four fastener. Three of them have been made from iron and they were corroded badly. One of them near the compass has been made from brass and it was oxidised. Some fasteners were taken from other instrument panels of VL Myrskys and in all six fasteners were blasted by glass beads and painted. The aim is that the best of the six fasteners will be installed to the MY-14

Fasteners' vibration absorbers have disappeared. A example has been found from VL Pyry. The new absorbers were manufactured from rubber seal and thin rubber plate. The used screws were original crews from the State Aircraft Factory.

Three out of four bakelite signs of the main instruction panel were disappeared. Luckily the signs could be substituted by using other instruction panels of VL Myrskys. The signs were sanded and the inscriptions were cleanded. After that the inscriptions were repainted. After sanding there is paint only in the inscriptions.

The sign showed the speed limit has to be fixed by glue and a thin background plate. The signs were fastened by 2 mm round-head screws.

Kommentoi kirjoitusta. Avainsanat: aviation history, restoring, old aircraft, VL Myrsky II, MY-14

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