Lanzo Duplex (oz10318)


Lanzo Duplex (oz10318) by Chester Lanzo 1937 - plan thumbnail

About this Plan

Lanzo Duplex. Rubber cabin/stick model. Plan shows both fuselage designs.

Quote: "Chester Lanzo's models always turn in a good contest performance. But the Duplex is probably the most outstanding of all his contest designs. The Duplex holds 2 records. At a contest last year it was officially timed at 48 minutes and 45 seconds, one of the longest official flights ever turned in by a rubber-powered model. For the past year this model has held the National Aeronautic Association record for cabin fuselage models. Since Lanzo is over 21, his record is catalogued as an Open Class Record to distinguished it from the Junior and Senior records turned in by modelers younger than 21 years.

Lanzo proved his modeling superiority by converting this same model into a hand-launched stick model and flying it for another official record. It was a flight of 18 minutes and 10 seconds. The only change Lanzo made in his model was to substitute a slightly different fuselage. In the hand-launched stick-model event, no landing gear is required, as the models are hand-launched. And, too, there is no restriction on cross-section area. So the stick fuselage is slightly shorter and considerably thinner than the cabin fuselage. In all respects the 2 fuselages seem very much alike. The stick fuselage is built up and carries the motor internally, just the same as the cabin fuselage. This is a more convenient way of distributing the strain of the powerful motor than suspending it from a single stick, as was done in the old-type models.

Both fuselages are built to fit the same nose and tail plugs. The wing is easily transferred from one to the other. The change from cabin-fuselage model to stick model is accomplished in a few seconds. Two-in-one is the best way to describe this model. By building one model, plus an additional fuselage, you'll have the benefit of two outstanding championship models. It's an inexpensive and convenient short cut in building up your quota of contest ships. Or, if you're a beginner, the Duplex should be an ideal way to acquaint yourself with the different types of contest models.

The Duplex was designed to conform to last year's weight requirements of 1 ounce per 50 square inches. Therefore, it will be necessary to increase the weight about 2 ounces to bring it up to this year's weight rules. Lanzo suggests the following changes to meet the weight rule of 3 ounces per 100 square inches: a slight decrease in elevator area of approximately 5 percent; a decrease in propeller area and a decrease in diameter to 17 inches; larger nose and rear plug to facilitate winding with increased amount of rubber motor; a more substantial landing gear to take care of the increased weight of the model; closer rib spacing in the wing and tail, and closer spacing between fuselage uprights; and an increase in power to about 30-35 strands of 1/8 in flat rubber.

The details of these changes are left to your own judgment. The plans as shown here are for the original model as it was flown by Lanzo.

First we'll describe the construction of the cabin fuselage. It's more difficult to build than the stick fuselage. 5/64 sq hard balsa longerons are used. If you're planning to increase the weight of the model, substitute 3/32 sq hard balsa longerons. The sketch of the fuselage is fully dimensioned and you should have little trouble in making a full-size layout on a piece of drawing paper. First draw the thrust line of the model and dimension all parts of the fuselage with reference to this line, as has been done on the sketch..."

Scan from DBHL, cleanup by theshadow.

ref DBHL-7382.

Direct submission to Outerzone.

Supplementary file notes

Article, thanks to Mary at


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Lanzo Duplex (oz10318) by Chester Lanzo 1937 - model pic

  • (oz10318)
    Lanzo Duplex
    by Chester Lanzo
    from Air Trails
    September 1937 
    42in span
    Rubber F/F Cabin
    clean :)
    all formers complete :)
    got article :)
  • Submitted: 28/07/2018
    Filesize: 452KB
    Format: • PDFbitmap
    Credit*: DBHL, theshadow
    Downloads: 534

Lanzo Duplex (oz10318) by Chester Lanzo 1937 - pic 003.jpg
Lanzo Duplex (oz10318) by Chester Lanzo 1937 - pic 004.jpg
Lanzo Duplex (oz10318) by Chester Lanzo 1937 - pic 005.jpg

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User comments

That’s the great Herb Kothe in one of his trademark Hawaiian shirts launching his cabin Duplex!
Bob Golden - 09/02/2024
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