During one final, highly focused work session, the closing plywood skinning was fitted to both wing spars. At 8 mm thick, these plywood strips proved considerably less cooperative than their thinner predecessors. The centre section therefore had to be pre-bent on the original spar form while damp and then allowed to dry completely before installation. The surfaces of all internal cavities were carefully sealed with varnish by experienced hands beforehand. The same applied to

At long last, work on the wing spars is moving forward again. The investigations and approvals required for the use of an epoxy adhesive were extensive and ultimately resulted in a 26-page report. Anyone interested in the finer details is welcome to download and study it using the link below. Last week, we received positive signals from Bern on our report, allowing the suspended work to resume. Naturally, we were already waiting in the wings. The individual plywood panels f

At the moment, I’m spending most of my time doing calculations, building test specimens and test rigs, and running tests — you know, the fun stuff. The pilot harness attachment has now passed its ultimate load test (finally). It’s bonded to the fuselage structure and, just in case that wasn’t enough, also bolted on. The calculations already showed that either the bonding or the bolts alone would be perfectly capable of taking the expected loads. But obviously, that wasn’t qui

No new blog posts don’t mean nothing’s happening behind the scenes – quite the opposite. At the moment, though, we’re facing a few challenges that are noticeably slowing down progress on the build. One of the main issues is proving a suitable epoxy adhesive for constructing the wing. But let’s take it step by step: After assembling the upper and lower spar caps, the next step is the side sheeting of the spars with plywood. The bonding area is very large and also geometrically

From four spar caps, the front and rear spars were constructed. In the space between the upper and lower caps are the webs and pillars that connect the two. The pillars in particular deserve closer attention: they serve to transfer loads, for example from the undercarriage, and may at first glance look like simple wooden blocks. In fact, they are made from cross-laminated spruce boards. The grain direction was also critical in the webs: it had to run vertically there, while t

Who still remembers the blanks for the spar caps? Most of those massive wooden pieces have now turned into shavings – and from twelve...