Macchi MB 308 (oz4244)

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Macchi MB 308. Rubber scale model.

Quote: "PEANUT MACCHI MB 308. Another 2-for-1 project, the Macchi was built at exactly double Peanut size - 26 inch span - so that the 50% reduction for the magazine is right on the button. Try 'em both. By WALT MOONEY.

For the Flightmasters' Annual Seaplane Contest this year, this version of the MB 308 was selected as part of an effort to win the rubber powered event. To be successful a model must be as aerodynamically clean as possible, and be stable enough to absorb the relatively high power that is required to get a seaplane off the water. What was required in my judgement, was a high wing airplane with as few struts as possible, this said 'cantilever wing', and my choices narrowed down to two; either the Cessna Airmaster on floats, or the MB 308 on floats. I opted far the Match' because it had an opposed engine instead of a radial, and because the strut system for the floats was much simpler. It happened that I had a photo of the real item with the license 'I-CARE', and that suited my sense of humor too.

The model shown flys beautifully and did win the rubber scale event. Interestingly, second place went to a model of the Airmaster!

As has been the practice a couple of times before in MB, the model was designed with a 26 inch wing span so that when reduced in half, it is exactly Peanut scale. The 26 inch span model used 3/32 square longerons, so that 1/20 square can be used on the Peanut. Also, 1/16 sheet ribs were used on the large one, and 1/32 should be used on the small one. Stringers were 1/16 square on the large one so they should be 1/32 on the Peanut. I have found that Peanut Scale seaplanes are hard to ROW, mostly because lie water is even further out of scale, so I have indicated the tricycle wheel landing gear on the plans, for the Peanut enthusiasts.

The airplane structure is the same old standard; fuselage sides built over the plans, sides removed and separated, cemented together at the tail and built into a fuselage box by adding cross pieces at each upright. Formers are added to the top and bottom cross pieces and stringers set in place. The nosebiock is solid balsa and the bottom cowl aft of the noseblock is also carved from black. The upper Cowl, back to the instrument panel, is wrapped sheet balsa. Wing tips, horizontal tail tips and the vertical tail outline were laminated, using model railroad basswood. The tail parts are conventional, flat, built-over- the-plants structures, which have soft wood caps added to the top and bottom..."

Update 23/05/2013: Added remainder of the article text, thanks to DonTilley.

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