1 to 2.5


230.3 inches


145.2 inches

Weight ca.

200 lbs+


Moki S400



My name is Harald Müller and I’m the founder and CEO of MHM Scale Aircraft.

I’ve been carrying the dream of building a metal model airplane around with me for the better part of 20 years. My company specializes in the design and construction of special order metal parts for TV sets and complex trade show exhibition booths. Throughout my professional life I’ve been privileged to have all the necessary tools and machinery at my disposal but I still thought it was impossible to build an all aluminum model aircraft the way I envisioned it—unless you intended to do it as a one-off project. That, however, didn’t interest me at all; my goal has always been the serial production of model aircraft made of metal.

Dreams, however, have a habit of staying with you. After I learned how to design my model aircraft on the computer with the help of a 3D CAD program, I figured out a way to integrate our computerized machines such as laser- and water jet cutters in the process of designing an all-aluminum model aircraft the way I really wanted to build it. That’s how it all began in 2003. Four years later we’d completed the prototype of our DHC-2 ‘Beaver’ in 40% scale. The aircraft has even been flown on floats!

After we’d decided that the DHC-2 Beaver would be our first aluminum aircraft and after we’d settled on the size of the model (1:2.5 scale), we started the process of gathering all available information: factory drawings, books, photographs and whatever else we could get our hands on. We also had the opportunity to extensively photograph and to take measurements of a Beaver that was once used by the U.S. Air Force to patrol the border between East and West Berlin during the Cold War. This aircraft is now owned by Deutsches Technik Museum in Berlin and currently stored at our factory in Ludwigsfelde.

Armed with all this information and the exact measurements of the original airplane, we completed a detailed 3-view drawing of the Beaver, which we subsequently turned into a three-dimensional computer model, utilizing a 3D CAD Program. Slowly, but surely, the more than 2,000 (!) parts such as formers, ribs, cowlings and door panels started to take shape in the computer.

Do you want to know how realistic our Beaver really is? Well, let’s do some math (don’t worry, it’ll be fun!). The original Beaver is built to 40% scale and the empty weight of the original Beaver is 1361 kg. If you scale this down (1361 kg/2.5³ or 1361 divided by 15.625), you arrive at an empty weight of 87.1 kg for the model Beaver. The prototype, however, tipped the scales at only 77 kg. When we checked the center of gravity it turned out that the aircraft was tail heavy and needed quite a bit of lead under the cowl—10 kg, to be exact. Let’s do some more math, shall we? The motor of the original Beaver, a Pratt & Whitney R-985 Wasp Jr. radial engine, weighs in at 300 kg. Scaled down to our 40% size, this engine would weigh 19.2 kg. But the Moki S400 weighs only 9 kg—there’s your missing 10 kg! Pretty incredible, don’t you think?

After extensive testing we have now started serial production, with four new models being built at our factory in the south of Berlin. The aircraft are for sale and can be outfitted with wheels, floats and/or ski. Even gadgets such as an on-board camera or a smoke system are possible. Maybe you’ll allow us to build one for you?

But the Beaver is not the only aircraft we’re working on—development on other 40% scale, all-aluminum model aircraft is underway and in full swing. We’re having a great time with it and I hope you’ll be just as excited as we are.

If you should have any questions please feel free to contact us. I really look forward to hearing from you.


Harald Müller

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