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Roland Sachsenhofer
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A model that I originally didn't want to build at allbut which was (and still is!) a lot of fun: Zlin 137 Agro

April 18, 2024 · in Aviation · · 10 · 158

The path to building this model of the 137 Agro is so entertainingly winding and full of twists and turns that I would like to start this report with a description of it. Sometimes the journey changes the perspective in such a way that the destination seems all the more interesting!
A first milestone was the acquisition of Eduard's excellent Zlin Z-37 Cmelak in a "Dual Combi" version. One look at the contents got me so excited that the box went straight to the pile of models that would be built in the near future. A short time later, however, an idea arose in my modelling plans that was to delay the start of construction of the Z-37 Cmelak double for the time being.

This is how it came about: a few years ago, my wife and I had a great encounter on a trip to the nearby Czech Republic: a Zlin Z-37A had just come to a standstill on a freshly harvested stubble field with a skilful tailwheel parking turn; the pilot in his shirt sleeves could be seen leaning relaxed out of the cockpit window while the running propeller chased the corn chaff and dirt across the field and the nearby road. At the edge of the field, a small tent was set up with a folding table, a cash register and a cashier, who communicated with the pilot via handheld radio. A couple waiting in anticipation completed the surprising scene and quickly made it clear: a spontaneous sightseeing flight was on offer here! We didn't want to miss out on this. The subsequent flight, the conversation with the pilot and the tour of the aircraft were a great experience for both of us and one that we still remember with a smile every now and then.

But what does this little story have to do with a report on the from ? When I held the components of the two Z-37 Cmelak in my hands, I had the idea of making my wife and I happy by converting one of them into the multi-seat Z-37A-3 that we were able to fly in the Czech Republic. So the project was born, now time and energy had to be invested in researching the prototype and planning the conversion. In principle, I had the confidence to rebuild the large "glass house" of the two-seater version, as most of the clear parts seemed to consist of flat surfaces. Nevertheless, the start of construction of Eduard's double had to be postponed for the time being.

Some time later, the story took another turn, as I came across the Z-37/Z-137 series from Kovozávody Prostějov (hereinafter referred to as KP). To my surprise - and delight - I realised that the main versions of this agricultural aircraft were offered here in an unexpectedly wide range, including the two- or three-seater "glass house" variant I had in mind. My plans therefore underwent a further change, as I simply could not avoid such a wealth of interesting models!

The current state of affairs is that I will build both Eduard models "out of the (well-equipped!) box", and a third model has even been procured. This will be the basis for a little Frankenstein exercise: I will only use the fuselage and cockpit of KP's two-seater Cmelak to build my multi-seater Z-37, the rest of the parts will be provided by the Eduard kit. The Z-137 Agro shown here will round off the planned quartet of Zlin's agricultural aircraft. In order to familiarise myself with KP's components, I also brought this build forward and built it as the first of the four Z-37/Z-137s.

About the Zlin Z-137 Agro
The close connection between the Z-137 and the Z-37 has already been mentioned: after the first flight of the XZ-37T prototype equipped with a Walter M 601B turboprop engine on 6 September 1981, production of the Cmelak was switched to the new version by 1983. In addition to the new engine, the wingspan was also increased to 13.63 metres by the addition of winglets. Just like its predecessor, the Z-137 Agro is extremely versatile and can be used as a spraying aircraft, for fire-fighting or as a towing machine. Production lasted until 1994 and around 50 of this last Cmelak version were produced. My model shows a Z-137T Agro used by the Hungarian company "Air Patrol".

Kit and building process
Numerous, mostly Eastern European manufacturers are currently bringing kits of exotic and rather rare aircraft onto the market, whereby the box contents usually fall under the definition of "short run". This is also the case here! The components of KP's Z-137 fulfil all expectations in this respect: thick-walled casting, powerful sprue pins or the absence of dowel pins fit into this picture, but the short run character goes even further: here you also have to cope with uncleanly cast components, which are framed by a lot of fish skin.
The accuracy of fit doesn't seem bad at all - once you have removed the individual parts from the overpowering casting frame and exposed the planned mould with a scalpel and sandpaper. Practically every part, large and small, has to be trimmed and prepared before it can be used. In the case of the undercarriage struts, I didn't want to have to deal with the messy, bent plastic rods that I had finally removed from the thick sprues, so I rebuilt everything from matching wire rods.

To bring some life into the model, the elevator was sawn off and reattached to the stabiliser at an angle. Details in the cockpit - instrument panel and the belts - as well as those on the undercarriage were taken from an etched parts set for Eduard's Z-37. The "M-92 wheel sprayer" attached to the model here was also borrowed entirely from the Eduard kit, as I didn't like the imprecise contours and few details of the KP version.
All the handles, footrests, rudder counterweights and aerials are also home-made from suitable wire. The exhaust pipes of the turboprop were made from hollowed-out cable insulation.

Unfortunately, I can't give the kit's decals a good report card either. They proved to be difficult to work with and broke quite easily in some places. What bothered me most of all, however, was the low opacity: for example, the white of the side stripes almost lightened to pink over the strong red of the paintwork, which then had to be painstakingly corrected with a dry brush and white paint.

In order to relativise the rather negative description of my impressions, I would like to point out the many positive and consistently praising reviews that this kit has already received on the www! I would also like to conclude these lines with a laudatory thought: KP has done a great job with this kit, which is essentially well realisable: it is very welcome that such important, attractive and, moreover, civilian aircraft types are receiving attention in model making!

Reader reactions:
3  Awesome

22 additional images. Click to enlarge.

10 responses

  1. An awesome result on a really unique subject, Roland!

  2. Another nice product of R.O. Sachsenhofer Flugzugbau AG!

  3. A not so often seen model, Roland @rosachsenhofer
    Beautifully done.

  4. Turned out very nicely, Roland, and is sure to bring back more happy memories for you and your wife.

  5. Very nice model, Roland. I’ve come to really like Ag planes. They’re regular visitors over our house with corn fields and sod farms adjacent to our property.

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