Early in 2002 Southern Sailplanes selected our workshops to assist in the rebuild of G-AHAG DeHavilland Rapide. The first parts to be worked on were the Tailplane, Elevators, Fin and Rudder followed by the mainplanes and subsequently the fuselage. I had already completed the rebuild of the structures which included applying new ply skins and repairs to ribs etc.
The mainplanes and ailerons were next requiring repairs to ribs, leading and trailing edge. The wings are held to shape by steel rods set at angles between the spars. My son Robin was very much involved on the rebuild from this point on. Having completed structural and repair work on each part was made ready to fabric. Suffice it to say the the rebuild work was extensive and the details are far too involved to cover these notes.
Application of fabric was the next step using Irish Linen. Irish Linen is a natural fabric and in applying it to an airframe takes a great deal of care to ensure that it will end up being taught as well as secured to the airframe part. Sky 4 Covers was asked to assist with the preparation and application of the fabric. Sarah King took a great deal of time studying the fabric application drawings as supplied by DeHavilland Aircraft. The drawings made clear the direction of the warp in the fabric, how the seams were to be sewn and how to join the fabric. Sarah not only has the expertise but she also had the machinery to make up each fabric envelope to be applied. As can be seen from the photo of the fuselage side that required a seam to run the complete length of the fuselage exactly over the stringer, On the wings can be seen the fabric having be applied doped and taped in place. The basics for the application of Irish Linen fabric to an airframe is to first ensure the the fabric fits as tight as possible with the trailing edge of say the wings being finally stitched in situ. The fabric is then lightly sprayed with sterile water to do the initial shrinking followed by several coats of high tautening dopes. All the leading and trailing edges are the taped and the fabric is stitched to each rib using a waxed rib stitching cord. All the ribs are then taped with pinked edged tape. The completed fabric and taping makes for a very satisfying picture of the work before the finishing paints are applied.
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