Lauantai 12.5.2018 - Member of Tuesday Club
The Finnish Aviation Museum Society’s Tuesday Club project to restore the Valmet Vihuri II (VH-25) front fuselage has taken almost twenty years. Now the restored part with front and rear cockpits is ready and on display in Hall I at the Finnish Aviation Museum.
The restored Vihuri front fuselage is based on the front cockpit and the engine mounting of VH-25 which were found in a scrapyard in Helsinki in the 1970’s and purchased to the Finnish Aviation Museum. The cockpit had some equipment and wind screen and the engine mounting had some fairing plate remaining. The restoration project started in the late 1990’s but was interrupted for a while and started again with full speed in the early 2000’s.
The front fuselage found in the scrapyard had only the front cockpit so the rear cockpit with its pilot’s seat had to be built following the original Vihuri drawings. Cockpit equipment and instruments found in the collections of the Finnish Aviation Museum and the Finnish Air Force Museum have been installed in the cockpits. The Tuesday Club team is grateful for the assistance of both museums for supplying the material. The Tuesday Club team built several new items for the cockpit, including the luggage compartment, map holder and flare gun with its launching tube.
The front fuselage of Valmet Vihuri II with its cockpits and its equipment is now in the Finnish Aviation Museum, on display for the visitors. The only remaining whole Vihuri (VH-18) I s in the Finnish Air Force Museum. However, the front part of VH-25 in the Aviation Museum offers the visitors something that the VH-18 in the Air Force Museum doesn’t.
The restored front fuselage of VH-25 is mainly covered with transparent plexi, not aluminium plate. Therefore the museum visitor can clearly see what equipment and instruments the Vihuri has.
The cockpit and display lighting is on, as well as the lights in the sight. Above the front seat there is a mirror for having a good view of the sight and its light cross.
The cockpit equipment and instruments in Vihuri are interesting because they originate from earlier plane types used in the Finnish Air Force. When the Vihuri’s were originally built, parts were installed from dismantled Air Force planes. For example the stick in the front cockpit of the Vihuri, the magneto selection switch, the red cockpit light and parts of the oxygen supply system (the regulator, the flow and pressure indicators and valve) come from Messerschmitt Bf 109.
The oxygen bottles of Vihuri are probably from Junkers Ju 88. The rudder pedals in the front cockpit are from VL Myrsky.
The instruments in the instrument panel come from several different planes. The manual pump of the pressurized oil system is from Bristol Blenheim. Unfortunately there is no Bristol Mercury motor available in Finland, so the restored VH-25 has no motor. As you can see, recycling of equipment and instruments has been a key issue in the building of Vihuri.
Welcome to the Finnish Aviation Museum to see the front fuselage of Valmet Vihuri II, restored by the Tuesday Club.
Photos: Lassi Karivalo.
Torstai 19.4.2018 - Member of Tuesday Club
The Finnish Aviation Museum has donated the models of BEA Hawk, Folland Gnat, Saab Draken and MiG-21BIS to the Aviation Museum Society’s Hawk Experience Center. The large wooden models were found in the storage room of the museum. The models need some repairs which will be completed in the Tuesday Club before the Hawk Experience Center season 2018 begins in May. The repairs of the BAE Systems Hawk Mk.51 model have already been described in an earlier blog.
After the Hawk model the next target was the Folland Gnat F.1 model. This model wasn’t badly damaged but the cockpit canopy was missing. In addition to some minor repairs the canopy had to be made.
To make the new canopy, first a wooden model of the canopy had to be made. The cockpit was emptied by removing the pilot’s seat and the instrument panel. This was necessary in order to be able to fit the wooden canopy model, made of balsa, in its place in the cockpit. At the same time the measurements were taken of the line where the canopy meets the edge of the cockpit: a metal frame will be fitted on the sides and at the rear end of the canopy.
A piece of balsa was carved slowly to match the shape of the canopy and the correct size by fitting it into the cockpit every now and then. Photographs and 3d-drawings of the Gnat were used to define the shape of the canopy. The wooden model began to take shape when it was gradually and carefully carved and buffed out and regularly fitted into the cockpit. Now the model for the canopy was ready.
Photos: Jorma Laakso.
Before making the actual canopy, the metal frame for the edge of the canopy was made. The wooden model was used to dimension the frame. The location of the frame was marked on the model in red lines. The image of the frame was drawn on a 0.3 mm thick brass sheet and cut off. The thin strips of brass sheet were honed to match the shape of the frame on the lower edge and the rear section of the cockpit and fitted on the balsa model. When the metal parts seemed to fit nicely into place they were soldered together. Now the metal frames were ready to be installed on the actual canopy.
Photos: Jorma Laakso.
The windscreen arc in front of the canopy was made of 0.8 mm thick plywood, laminating four layers of plywood on top of each other. The laminated arc was milled and buffed out into shape. Then a windscreen made of transparent plastic sheet was attached, using a friction-type connection.
Photo: Jorma Laakso.
The making of the actual canopy was started, using the balsa model and a mould. A heated plastic sheet is pressed against the opening in the mould, using the balsa model for pressing. The mould was made from 4 mm plywood with an opening matching the shape and dimensions of the outer edges of the cockpit.
Photo: Jorma Laakso.
A piece of 10x10 cm was cut from a 0.5 mm thick GAG-PET sheet. The sheet of plastic was attached by its edges on top the opening in the plywood mould. The sheet of plastic was heated using a hot air blower. When the surface of the plastic was soft enough, the sheet was pressed evenly into the opening in the mould using the balsa model. The stoppers on the sides of the balsa model prevented the model from pressing the sheet of plastic too deep into the mould.
Photo: Jorma Laakso.
It took about one minute for the plastic sheet to cool down, then the balsa model was removed. A bulge had formed under the mould, shaped like the balsa model. This was the rough form of the canopy. The GAG-PET sheet was removed from the mould and the bulge, i.e. the preformed canopy was cut off.
Photos: Jorma Laakso & Lassi Karivalo.
Now the metal frames (at rear end and lower sides of the canopy) and the windscreen arc could be attached to the canopy. The canopy was placed on the balsa model where the red markings showed the exact place of the frame. When the metal strips had been placed exactly on the marked lines, they were glued in place using UHU POR contact glue. Now the extra plastic material below the frame could be cut off. When the canopy was placed on top of the cockpit to test how it fitted, the result looked good. UHU POR contact glue was used to glue the windscreen arc to the canopy. Then the canopy frame and the windscreen arc were painted dark green.
The last phase of work was to attach the new canopy on the Gnat model. The canopy was placed on the edges of the cockpit and attached with Plastic Padding. When the seam had dried it was honed smooth and painted dark green. The Folland Gnat F.1 model had a new canopy and is now ready to be placed on display in the Hawk Experience Center.
Photos: Unless separately mentioned, Lassi Karivalo.
Keskiviikko 21.3.2018 - Member of Tuesday Club
A wooden model of BAE Systems Hawk Mk 51 jet trainer was found in the storage room of the Finnish Aviation Museum. The partly damaged model is approximately 50 cm long and it represents HW-310 which was in use in the Finnish Air Force. HW-310 belongs to the series of Hawks which were assembled by the Valmet Aviation Industries between 1980 and 1985. The real HW-310 has been withdrawn from use and stored. The State of Finland will donate it to an aviation museum in Switzwerland (Clin d'Ailes - Musée de l'aviation militaire de Payerne) and where it will probably be transported already this spring.
The museum has no information about the builder of the HW-310 model. Originally the model has been attached by its landing gear on a white plywood board which has been hanging on the wall. So the model has been a wall decoration.
The model is very well made and its proportions match the original aircraft. The cockpit has seats and its main equipment – also made of wood. The instruments on the panel have been painted, decals haven’t been used. The model has been painted according to the old camouflage scheme (black/green/grey) used in the 1980s, which suggests that the model was probably made about twenty years ago. Today the planes are painted all grey with small national insignia.
Photo: Jorma Laakso.
When the Hawk model was found, the idea of bringing it on display in the Hawk Experience Center of the Aviation Museum Society was brought up. The center has on display the cockpit section of HW-314, which belonged to the same Hawk production series as the real HW-310. The model of HW-310 could be used to illustrate what a whole Hawk looks like. There is an existing showcase where the HW-310 could be on display. An additional advantage is that the HW-310 has a similar black/green/grey camouflage scheme as the HW-314 in the Experience Center.
The Finnish Aviation Museum decided to donate the HW-310 model to the Hawk Experience Center and the Tuesday Club set out to work. The model was moved from the storage to the club workshop. The model had some damages: the nose landing gear was broken, one of the horizontal elevators was loose, the seam of the vertical elevator and the fuselage was broken and the cockpit canopy was loose and slightly broken.
Fortunately the damage wasn’t serious and repairing wasn’t difficult. The right side horizontal elevator was glued into place, the seam between the vertical stabilizer and fuselage was re-glued and painted. The split wheel on the nose landing gear was repaired. The canopy of the cockpit didn’t quite settle in its place and some modifications were needed on the canopy and the rear seat in order to have the canopy in the correct position.
As the model had originally been hanging on the wall, it hadn’t been balanced to be standing on its landing gear. When placed on a horizontal surface the rear-weighted plane’s tail is pointed downward. Therefore an additional support has to be added under the rear fuselage when the model is in its showcase.
The Tuesday Club team discussed whether the HW-310 identification marking should be changed to match the identification of HW-314 in the Experience Center. The decision was negative. It would have been difficult to modify the last number of the identification marking from a four to a zero so that the change couldn’t be noticed on the original paint. So the original appearance of the model was respected and no changes were made.
The HW-310 model is made of solid wood and is very robust but it still needs a good storage and transportation box. A new box was made from plywood and wooden battens. The box has a hinged lid and it was painted with clear varnish. The box and the lid have supporting pads which were cut to measure and support the weight of the model during storage and transport.
The Hawk model and its box are ready. The model was placed in the existing showcase to see how it fits there. And it looks great!
Fine, isn't it?
Now HW-310 is waiting for the summer exhibition round of the Hawk Experience Center to begin. The first event is already in the horizon: The “Military Aviation as a Profession” –event will be arranged by Satakunta Air Command in Pirkkala, Tampere on May 15th.
Photos (unless otherwise individually mentioned): Lassi Karivalo.
Sunnuntai 4.3.2018 - Member of Tuesday Club
The cockpit of VL Vihuri (VH-25) will soon be placed on display at the Finnish Aviation Museum. The last phase in the cockpit restoration work includes the side coverings. The sides are covered with aluminium plate and plexiglass so that the museum visitor is able to have a view inside the cockpit and see all the equipment there.
While the covering of the sides has been going on, the last of the cockpit equipment have been installed. The Tuesday Club was able to get hold of a machine gun camera control unit which has been in a Vihuri. The only problem was that the unit didn’t have the bracket which is needed to attach it to the instrument panel on the left side of the front cockpit. There was no information available about the original bracket. Therefore the bracket was designed by the Tuesday Club and built using aluminium. The bracket has now been made and the control unit is ready to be installed.
The cockpit and display lighting was completed before Christmas. The finalisation and installation of the lighting control unit was left to be done later. A container was made from aluminium plate to house the lighting control unit. The whole package was installed on the supporting frame under the front cockpit. The lighting control unit was placed behind the cockpit side covers, hidden from view and also protected from possible vandalism.
The covering of the lower parts of the cockpit sides using 1.5 mm aluminium plate has been completed. The aluminium plates cover half of the cockpit sides. The plates were attached at their lower edge to the supporting structure’s hem under the cockpit. The upper edge of the plates was attached to the covering panel which runs along the side of the cockpit. The upper sides of the cockpit will be covered using transparent plexiglass. The plexi installation has already been started.
Photos: Lassi Karivalo
Keskiviikko 20.12.2017 - Member of Tuesday Club
The last phases in the restoration work of the Valmet Vihuri II (VH-25) cockpit included the installation of the cockpit lights, the instrument board background lights, the light of the sight and the display lights when the cockpit is in the museum. Finally the sides of the cockpit will be covered with aluminum plate and plexiglass.
Originally the Vihuri had a 24V direct current electrical system. The positive pole of the system was insulated from the fuselage of the plane and the negative pole was connected to the fuselage. However, in the restoration of the Vihuri cockpit a 12 V alternating current system was chosen. In this system both poles of the system are insulated from the fuselage. The mains voltage (240 V AC) is transformed into a low voltage (12 V) and rectified to direct current. This power supply (12 V DC) is connected to the Vihuri lighting control panel, which supplies power to each lighting fixture.
The front and rear cockpits of the Vihuri has small red lights on both sides of the cockpit. The light is tinted red in order to disturb the pilots’ night vision as little as possible when flying in dusk or in darkness. The amount and direction of light can be adjusted simply by turning the shade around the glass of the lighting fixture.
Three original cockpit lights were available and could be installed into the VH-25 cockpits, but the fourth lighting fixture was missing and had to be made. Fortunately the base of the fourth light was found. The body, the glass and the turning shade of the lighting fixture had to be made to resemble the original ones. The body was made of aluminum, the “glass” was cut from red plastic and the cover was made from aluminum plate.
When the fourth cockpit lighting fixture was ready, all four lights were installed in the cockpit by attaching them to the original fasteners in the upper parts of both cockpits. The original incandescent lamps were replaced by led lamps. Leds were chosen because the cockpit lights are always on when the VH-25 cockpit is on display in the museum and the heat emitting incandescent lamps wouldn’t be a good solution. Installing the led lamps into the original lighting fixtures wasn’t a problem because the leds have the same type of socket (BA 15d) as the original incandescent lamps.
The original power cables of the four cockpit lights in the Vihuri are protected by transparent plastic tubes. A similar installation was chosen in the restoration work, but using similar thin silicon tube. In the original installation there were two cables (positive and negative) from each lighting fixture installed into the plastic tube and the negative cable was connected to the fuselage. The cabling was changed so that both cables are inside the tube and they connect the lighting fixtures to the lighting control panel. The red lights were turned on when the power was connected.
Three background lights were installed behind each instrument board. Unfortunately there were no original background lights available and all of them had to be made. Fortunately the instrument boards still had the clips for the lighting fixtures so that the size and shape of the lighting fixture could be estimated.
The tube-shaped bodies of the lighting fixtures were lathed from plastic. A cable was pulled through the body and the wires were attached to the base of the fixture. Led lamps with G4 caps were attached to the base. When power was supplied to the cables, the background lights illuminated the instrument boards.
The cabling was made by using one cable from the lighting control panel to each instrument panel. According to the drawings of the original installation, the wiring was branched at the instrument panel to supply each of the three lighting fixtures. The light of the sight was installed in a similar way.
In the Vihuri the background lights of the instrument boards and the sight light had originally armored cables. The armor, i.e. the braided metal covering of the cables, was meant to protect the power supply from disturbing external signals. However, the armored cable used in the restoration work of the instrument panel lights had three cables whereas the original one had only two. Therefore the three-wire cable was pulled out of the armor and replaced by the two wires leading to the instrument board lights. At the same time the armor was stretched in order to make it thinner, resembling the original one used in the Vihuri.
The Vihuri cockpit will be on display in the Finnish Aviation Museum. The red lights in the cockpits, the instrument board lights and the sight light were adequate for the pilots but they won’t be able to illuminate the cockpit enough for the museum visitors. Therefore four 30 cm long led tubes were installed as display lighting. The leds were attached to the upper edges of both cockpits, trying to install them as unnoticed as possible. Depending on the position of the cockpit in the museum, the lights will be controlled so that the leds are on only on the side where the viewer is standing. In this way the lights on the opposite side will not produce disturbing glare.
Now the cockpit lights in the Vihuri as well as the instrument board background lights, sight light and the display lighting were working. The last phase was to organize the various cables from the lighting fixtures to the lighting control panel into a tight group. This was done by attaching the cables to the cockpit frame tubes by using original clips and new clips made to match the original ones.
Lauantai 14.10.2017 - Member of Tuesday Club
A common problem in aviation museums is that the planes on display are covered with dust. The Finnish Aviation Museum makes no exception. The planes hanging from the ceiling as well as the ones on floor level were in need of cleaning. One of the reasons for this is that the museum doesn’t have the staff to keep the plane surfaces clean.
The Tuesday Club members of the Aviation Museum Society decided to lend a helping hand and arranged two events in the halls I and II in the Finnish Aviation Museum to clean the planes standing on floor level. The work had to be limited to what could be done without a man lift and without building any scaffolding.
The surfaces of the planes were vacuumed, wiped using a damp cloth and dried. The wiping cloths were rinsed in plain water. Cleaning chemicals were not used to avoid possible harmful effects. A half-tall A-ladder was needed to reach the surfaces that were higher up, such as the upper surfaces of fuselages and wings. Tall A-ladders could not be used for safety reasons.
The plane surfaces where partly covered with a thick layer of dust and the cleaning rags had to be frequently rinsed in water. The water in the bucket soon turned nearly black and had to be changed. Also the cleaning rags became quickly too dirty to use and had to be thrown away and replaced by clean ones. Judging by the amount of water and rags used, the majority of the dust and dirt was definitely wiped off and rinsed into the Vantaa city sewer system.
After the work of several hours nearly thirty planes had been cleaned and are now tidy and clean for the museum visitors to see. Unfortunately this doesn’t apply to all of the planes in the museum, including the Convair Metropolitan, the DC-3 or the Lockheed Lodestar – not to mention all the planes hanging from the ceiling of the museum halls. A man lift or large-scale scaffolding would be needed to clean the surfaces so high up in the display area. Using a man lift would be the most appropriate arrangement but the museum doesn’t have one.
Although man lifts are not cheap to purchase or to rent, we hope that the Aviation Museum could invest in one so that all the large planes and the hanging ones could be kept clean and tidy – as the old planes deserve. Or maybe a supporter of the Aviation Museum could donate a new or a second-hand man lift to the museum?
Sunnuntai 9.4.2017 - Member of Tuesday Club
The Tuesday Club is known for its conservation and restoration work of museum aircraft. But when needed, its members are also active doing other things. Lately, one such “other thing” has been the Hawk Experience Centre of the Aviation Museum Society. This movable “mini-museum”, including the cockpit section of a BAe Hawk Mk.51 has been a frequent crowd-raiser at numerous air-shows and exhibitions. In a short time thousands of boys, girls, women and men have experienced their first “cold type” flight in an aircraft still in wide use in air-forces around the world.
But the Hawk Experience Centre is much more than just taking a “flight” in a cockpit-section. At the centre information about the Aviation Museum Society (Finland) and about the activities of all Finnish Aviation Museums is given to a waste number of individuals who might not otherwise get this information. At the Hawk Experience Centre the visitors can also buy article put on sale by the Aviation Museum Society and the different aviation museums. The more the public knows about what the Finnish Aviation Museums are doing and keeping available for their visitors the more likely they are to pay them a visit. Increasing the number of visitors is an important enabler for the continuous development of the activities of the aviation museums.
The available activities and the equipment of the Hawk Experience Centre are continually refined to provide the visitors a still better experience. This is where the Tuesday Club enters the picture. Its most recent work was the making of the “safe storage/transportation” boxes for the centres three big displays to replace the original cardboard-boxes that were falling apparat.
Based on measurements of the old cardboard-boxes plans for improved wooden ones were made and drawn. The new boxes are made of two main parts, the bottom one and the top on that can be slid over the bottom one. In this way putting the display into the box and removing it from there was made much easier as you do not have to reach so deeply into the boxes to move the displays. The boxes were made of 6 mm softwood-plywood and pine-laths with the bottom made of 18 mm weatherproofed plywood. The boxes were dimensioned to allow using the original EPS shock-absorbing units in the new boxes.
So, off we went to get the plywood and laths. Once we had them in the workshop it was time to cut them to measure and assemble the parts into boxes gluing together the plywood parts and pine-laths. To be safe and not sorry, the joints were strengthened by stapling using a pneumatic stapler.
Wooden handles were fitted to the ends of the boxes. Support-laths, that also function as fenders when the boxes are stored close together were fitted to the top-and bottom of the long sides of bottom part of the boxes.
With the carpentry done it was time for some finishing touches including painting the boxes. The decision was made to paint the boxes in neutral grey. The grounding was done using white Ferrex-paint and the finishing was done using semi-gloss Futura furnishing-paint. When the paint had dried latches were put in place to keep the top and bottom parts connected.
Even though the boxes were made as “series production” we applied the pre-WWII Rolls Royce quality principles. Thus the top and bottom part of each box ended up not being interchangeable but being pair-specific. To ensure smooth use of the boxes the individual pairs (top/bottom) were marked with paired, one, two and three, dots.
This done, we could insert the EPS shock absorbing material from the old cardboard-boxes into our new wooden ones and then take the new boxes from the restauration shop to the Hawk Experience Centre in the yard of the Finnish Aviation Museum.
There the displays were put into the new boxes, one after another to await their next use at the Hawk Experience Centre at some yet to be held fair or aviation show.
But the experience-centre is much more than just taking a “flight” in a cockpit-section. At the centre information about the Aviation Museum Society (Finland) and about the activities of all Finnish Aviation Museums is given to a waste number of individuals who might not otherwise get this information. At the Hawk experience-centre the visitors can also buy article put on sale by the Aviation Museum Society and the different aviation museums. The more the public knows about what the Finnish Aviation Museums are doing and keeping available for their visitors the more likely they are to pay them a visit. Increasing the number of visitors is an important enabler for the continuous development of the activities of the aviation museums.