The engine-mounting front-plate for the Kurki has been finished

Tiistai 25.4.2017 - Member of Tuesday Club

Suomeksi

The I.V.L. K.1 Kurki was brought for conservation without the engine-mounting front-plate and without the aluminium-plate side and top covers. The engine of the Kurki is fastened, or rather should be fastened, if we had an engine, to the mountings front-plate. Regrettably, we have no nine-cylinder radial Siemens-Halske Sh 12 engine available for this purpose. So if anyone knows that there is one available, hidden in a hangar or garage, please let us know. We´d be most happy to have on, even if just on loan. Engine or not, we decided to make and fit the missing engine-mount front-plate as well as the side and top covers.

As no plans of the Kurki have survived, we modelled the front-plate after the one on the VL Sääski (SÄ-122) on show in the exhibition hall I of the Finnish Aviation Museum. We did this, because both the Kurki and the Sääski were designed at the Aviation Forces Aircraft Factory at Suomenlinna in 1927 and both had a nose-mounted Siemens Halske Sh-12 engine. Thus it is most probable that they both had very similar or maybe even identical engine mounting plate and engine mounting. The engine mounting-plate of the SÄ-122 is made of thick plywood with the front part covered with an aluminium plate. Thus we chose 18 mm plywood for the plate, which was to be covered with an aluminium plate.

We started making the front-plate by establishing the form and height of the plate. This was done by attaching a piece of cardboard to model the missing engine-mounting top covering-plate. This allowed us to establish the form and height of the front-plate. Its side- and bottom measures were determined by the other parts of the engine mounting. When the rough measures of the front-plate established a sturdy model was made of cardboard. By making a model we wanted to make sure we had the correct form for the end-plate. The cardboard model was attached to the engine-mounting and some finishing modelling was done.

Using the finalised cardboard model a plywood end-plate preform was cut. The preform was then clamped to the engine-mounting to enable the correct positioning of the holes for the large-diameter fastening bolts going through the corners of the plate. When their position had been determined, the holes were drilled. Now the plate could be bolted in place and the holes for the other 10 fastening bolts could be drilled. After this we did some finishing work and sanding on the edges of the plate. Finally we made the round opening in the plate, enabling the installation of the engine. The size and position of this opening was calculated using the opening in the engine mounting-plate of the Sääski SÄ-122 as a starting point.

Before we begun to attach the aluminium cover-plate on the engine-mounting front cover we had to establish how this plate, the top covering plate and the side-plates attached to each other. From pictures of the Kurki we could determine, that the engine mounting front-plate was situated under the other. The top cover was installed atop of it and the side covers on top of this, covering both the top cover as well as the front-plate cover.

Covering the plywood front-plate was started by covering its sides using an aluminium strip some two centimetres wider than the edge of the covering-plate fit with the front and sides of the plate and bending the rest to go behind the plate. The strip was nailed to the sides of the plate using small nails and to the back of the plate using tacks.

Then the front of the plate was covered using 1.2 mm thick sheet aluminium. A piece was cut out the aluminium sheet to the shape of the front mounting-plate but to a size some centimetres wider than the plate. Thus the edges of the cut sheet could be bent to form a trough going over the edges of the plywood plate. The edges of the sheet were bent in a press, after which the holes for the fastening bolts were drilled. Now the aluminium covering sheet could be test-fitted the plywood cover-plate for the first time and the complete front cover-plate test-fitted to the engine mounting. It was a nice fit!

But we still had to make the hole, needed for the fitting of the engine, in the aluminium sheet.  Thus the sheet was removed from the plywood-plate and a hole about one cm smaller than the one in the plywood-plate was cut in the sheet. Thus the edges of the hole in the aluminium-sheet could be chased into a collar over the edge of the opening in the plywood-plate. Now the final fitting of the aluminium sheet cover could be attached to the plywood engine mounting front covering-plate. This having been done, the completed covering plate could fastened to the engine mounting.

Wing of Kurki to Tuesday Club

Lauantai 4.2.2017 - Member of Tuesday Club

Suomeksi

Since the spring 2016 the Tuesday-Club has been doing conservation work on Kurki Fuselage. Until now it has not been possible to start work on its wings, stored at the Päijät-Tavastia Aviation Museum in Vesivehmaa, because the other ongoing projects have taken up so much space in the workshop at the Finnish Aviation Museum.

However, now that the Kurki fuselage has been moved to the museums hall for changing exhibitions, there is enough space in the workshop for the Kurki wing. Well, not for the whole wing, but for one of the halves. Compared to the size of the Kurki, the wing is rather big – with a total span of 12.3 m (including the width of the fuselage) each wing is 5.75 m long and 2.32 m wide – quite a kite!

On January 24th, the Kurki fuselage was moved to the changing exhibitions hall, were conservation/restoration work on it is continuing. At the moment work on the aluminium engine installation cover-plates is ongoing. The top one is fixed but the side-covers can be opened to allow access to the engine mount area. The covers are made of 1,2 mm thick aluminium-plate.

On Monday January 30^th, a Defence Forces interchangeable-platform lorry performed a conscript driver’s special-transport training mission. Coming from Tikkakoski it arrived at the Vesivehmaa airfield where it unloaded its enclosed platform to the ground in front of the back doors of the museum hangar at Vesivehmaa. The right wing of the Kurki was loaded and securely tied-down into the enclosed platform. It was a close fit. The enclosed platform was lifted back onto the lorry and the trip to Vantaa could begin.

After a couple of hours the precious cargo was at the door of the restoration workshop at the Finnish Aviation Museum at Vantaa and the wing was moved into the workshop. Mission completed – with benefits for all parties – the War Museum (owner of the Kurki), the aviation museums and the Defence Forces. Many thanks to all parties taking part in this operation.

Both halves of the wing have been damaged, both mechanically and by rot during their 90 years in storage. The Kurki was stricken off the books and put into storage in 1927. There are about 30 holes of different sizes in the plywood surfaces of the right wing. In places the plywood has rotted to a degree requiring its replacement.

However, the wing is in better condition than the upper wings of the I.V.L. D. 26 Haukka I. But plenty of hard work and elbow-grease will be needed before the work is done. We can begin the actual work after finishing the “current condition check” and the thorough cleaning of the surfaces. The cleaning has already begun.