Tail boom stabilizers of Mil Mi-8P (HS-6) are being covered

Tiistai 14.9.2021 - Tuesday Club member


Suomeksi

The tail boom stabilizers of the Mil Mi-8P (HS-6) helicopter, which is on display on the yard of the Tuulonen shopping centre, have been brought to the Tuesday Club to be repaired. The HS-6 helicopter was on display outside the Finnish Aviation Museum for a long time then, some years ago, it was moved to Vesivehmaa, to stand in front of the Päijät-Häme aviation museum hall. The helicopter was approaching scrapping, but fortunately a place was found for it at the Tuulonen shopping centre. The shopping centre has quite a remarkable collection of different aircraft on display: Saab 35FS Draken (DK-247) and MiG 21 BIS (MG-124) fighter jets on the yard and Douglas DC-2 (DO-1) “Hanssin Jukka” and Focke Wulf Fw 44 Stieglitz (SZ-18) indoors. The shopping centre can already be called a small aviation museum.

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The tail boom stabilizers of HS-6 consist of an aluminium frame and are half covered with fabric. The fabric covers the area between the stabilizer’s trailing edge and the spar, about half of the stabilizer’s area. The fabric areas have been badly damaged because the HS-6 has been standing outside since the Defence Forces removed it from service in 2007.

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The task of the Tuesday Club team is to remove the decayed fabric covering and to replace it with a thin sheet of aluminium. The Mi-8 can’t be considered an actual museal artefact anymore and the fabric covering would rot again as the helicopter is permanently on display outside the Tuulonen shopping centre.

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The work was started by removing the rotten fabric from the stabilizer. The aluminium ribs and other surfaces, which had now been revealed, were cleaned. The stiffening steel batten, running parallel to the stabilizer’s spar, had rusted and it was cleaned. The paint on the stabilizer’s aluminium surface had partly flaked off. The flaked paint was removed, and the surface was cleaned to clear aluminium.

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A cardboard model was made of the stabilizer’s surface which will be covered with a sheet of aluminium. The covering sheets will be cut from aluminium plate according to the cardboard model and riveted on the upper and lower side of the stabilizer. The cardboard model was fitted on the upper and lower surfaces of both stabilizers. It turned out that the Russian helicopter engineers has designed the stabilizers to be symmetrical. This means that the cardboard model can be used for cutting adequately accurate aluminium sheets for the upper and lower surfaces of both stabilizers.

Photos: Lassi Karivalo

Avainsanat: aviation history, restoration, Mil Mi-8P, HS-6