Indoor Tractor (oz7287)


Indoor Tractor (oz7287) by Merrill Hamburg 1928 - plan thumbnail

About this Plan

Hamburg Indoor Tractor. Freeflight, tractor monoplane, rubber power. Span: 19in. Author: Merrill Hamburg, A.M.L.A. Publisher: The Ronald Press Company. Manufacturer: A kit was sold by the A.M.L.A. which cost 75 cents, postpaid.
Year: 1928. Plan Size: 11in x 8.5in. Status: Complete, except prop. Source: Paul Edward Garber, Building and Flying Model Aircraft, RonaldPress, 1928, page 176. Scale: 1/1.97 digital file.
Notes: Scannedand edited in PC Paint. I added a title block. The 19in span is 9.64in on the digital file, thus the scale ratio of 1.97. The size in a print will depend on settings in the printer software. The original book drawing was 5.28in x 3.90in. Enlarging to print fullsize would not be practical; build on a pencil drawing. Note the initials PEG at the bottom right. Note detail differences between this and the ones published by Hamburg. This motor stick tapers to the ends. No prop is shown, but the text says to carve the prop from a 3/4in x 1 1/4in x 10in block of balsa. Hamburg says to use an 11/16in x 1-1/4 x 10in block, but to try an 11in prop. Motor is a 16in loop of 1/32 x 1/8 rubber. This plane was reported to fly for two to three and a half minutes. This is essentially the same plane published by Hamburg in 1927 and 1928.

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  • (oz7287)
    Indoor Tractor
    by Merrill Hamburg
    19in span
    Rubber F/F
    clean :)
    all formers complete :)
  • Submitted: 08/12/2015
    Filesize: 91KB
    Format: • PDFbitmap
    Credit*: GaryHinze
    Downloads: 1015

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This model plan (like all plans on Outerzone) is supposedly scaled correctly and supposedly will print out nicely at the right size. But that doesn't always happen. If you are about to start building a model plane using this free plan, you are strongly advised to check the scaling very, very carefully before cutting any balsa wood.


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