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Welcome to the BD5CLUB! Would you be able to provide a background on your BD5 and some photos! You are our first South African member! Looking forward to receiving updates.
Jeff Brenhaug ( @hueychief) did a test bend on some extra pieces made specifically to get the roller and bending jig marks set. He reported that they turned out pretty good.
With things settling into the new workshop, I was able to get the NPT301 turbine back out of it’s transport case and up onto the workbench for a clean down, in preparation for our Aeronautical Design Engineer, Matthew Fortuin, to commence his work. Matthew will be producing a detailed set of drawings and plans for an entirely new fuel control system, oil system, engine control computer and other accessories etc.
This work will enable us to get rid of the heavy 1989 components (to which we have no documentation for), replacing them with modern and lightweight alternatives that are reliable and that we can service and maintain.
Another goal of the work is to reduce the overall turbine weight, which currently stands at 45kgs dry. We are confident that a 5kg reduction can be achieved.
We will also need to modify the inconel thrust tube (lengthen it 350+mm) to fit the BD5J fuselage.
Managed to get a clear Saturday to get the canopy perspex cut. To assist, I invited a couple of mates to come give me a hand, and between the three of us, we managed to successfully cut the perspex without destroying it.
We took things slowly and gently cut our way around the perimeter of the canopy using the Ryobi 4″ cut off saw with a 1mm fibre cut off wheel, with my two friends helping keep the perspex supported.
The temperature was around 30degC so the perspex was quite warm and pliable.
The photos don’t really convey the time and effort it took to work our way around the edges. The reason for this, was that we could not make long cuts, as the cut-off disc would heat the perspex up too much and begin to bog down. Further, as the cut ran along a curved path, the trailing side of the disc would kick-out, so we found the best method was to make 4 inch cuts and then make a 90deg intersecting cut to remove the unwanted perspex. This obviously made things go a little slower, but gave us a cleaner overall cut.
Once the canopy perimeter was cut entirely, we then spent an hour filing the edges smooth and de-burring edges.
The next stage will be to spend time refining the canopy to fuselage fit, which will require a few hours of filing and sanding to get everything matched perfectly. To do this however, we need to temporarily attach a number of support flanges around cockpit sides so that we can fit the entire perspex as a single unit. This is largely because we do not have the main canopy frame installed on the fuselage at this time.
The day ended with a small get-together of sport aircraft builders and pilots who all have an interest in the mighty BD5, with a BBQ and Sausage Sizzle for everyone to enjoy.
Looking forward to getting back into things next weekend!
Update and Photos courtesy of Andrew Vincent:
December 22nd, 2022: An exciting day today for me, as we conducted the first ground run of my BD. Quite a noisy little engine but performed flawlessly and exactly as promised by PBS in the Czech Republic. A couple more ground runs, then onto high speed taxiing to bed in the brakes.
