For the past several work sessions, I have been working on the baffling. The design of this airplane's cowling has three "ducts", if you will, at the front. The bottom duct, sometimes referred to as the "scoop", directs air into the filter air box and then to the fuel injectors where, mixed with fuel, it goes in to the engine for combustion. I'll do that assembly later. The other two ducts, on either side of the spinner, direct air over the cylinders to cool them (it's an air cooled engine, like an old VW).
To keep drag down, the ducts are small, so its necessary to use the air ultra efficiently. The baffling accomplishes this by routing the air, without leaks, directly where it needs to go. The key is WITHOUT LEAKS. Also, the oil cooler, also cooled by the directed incoming air, needs to be positioned just so, to receive enough flow. Finally, there are three blast tubes to direct some air over the primary alternator, the magneto and the electronic ignition.
Photos follow:
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| Starting the baffling construction |
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| Left side cylinders and start of oil cooler positioning |
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| Overhead shot |
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| The baffles aren't yet trimmed down to fit the upper cowling |
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| Forming the left inlet ramps |
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| Another view of left inlet ramp |
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| Checking fit with lower cowling |
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| Starting to look good |
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| There are primary and secondary bends to get the ramp lined up |
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| Right inlet ramp |
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| Holding upper cowling a fixed distance above lower to mark baffling for trimming |
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| Epoxying the upper cowing inlet ramps (pencil marks show center baffle position) |
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| More epoxy and filler will be used to smooth the ramps |
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| Oil cooler, mounted as high as practical |
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| Mounted high to stay out of the way of airflow over rear cylinder |
