Duplex (oz4235)


Duplex (oz4235) by Chester Lanzo 1988 - plan thumbnail

About this Plan

Lanzo Duplex. Free flight rubber model. Nationals-winning design. The duplex refers to the model being used both as a stick and as a cabin design.

The Lanzo Duplex (oz10318) was originally published in Sept 1937 Air Trails. This here is a later re-drawn plan for Old Timer of the Month by John Blair in MB, 1988.

Quote: "Old Timer of the Month: Duplex. Design by Chet Lanzo. Plan by John Blair. Text by Bill Northrop.

The 'Duplex' was a featured construction article in the September 1937 Air Trails magazine. The model was designed by Chet Lanzo for the 1936 weight rules (one ounce per 50 sq in). Fuselage construction was 5/64 inch (!) square balsa. The construction article recommends (and I concur) that the model be built to the 1937 rules (three ounces per 100 sq in). This is accomplished by using 3/32 hard balsa for the fuselage construction, adding wing ribs, and adding rubber - up to 36 strands of 1/8 in - to bring flying weight to six ounces. Of course, vbe wouldn't try to use that much of today's hotter rubber; would we?

Under the 1936 rules, the Duplex held two National records: 48 minutes, 45 seconds as a fuselage model and 18 minutes, 10 seconds as a stick model.

Editors Note; Is there doubt in anyone's mind, that Chet Lanzo's designs were the inspiration for some famous competition models that came from the same area of the country several years later?"

Direct submission to Outerzone.

Supplementary file notes

Planfile includes article.


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Duplex (oz4235) by Chester Lanzo 1988 - model pic

  • (oz4235)
    by Chester Lanzo
    from Model Builder
    April 1988 
    42in span
    Rubber F/F Cabin
    clean :)
    all formers complete :)
    got article :)
  • Submitted: 14/04/2013
    Filesize: 748KB
    Format: • PDFbitmap
    Credit*: theshadow
    Downloads: 999

Duplex (oz4235) by Chester Lanzo 1988 - pic 003.jpg

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