AM.9 (oz14858)

About this Plan

AM.9. Free flight glider model. Wingspan 2180 mm.

Direct submission to Outerzone.

Update 11/10/2023: Added later article from FMT, Sept 1989, thanks to Pit. This shows a modified version for electric power and RC.

Quote (google-translated from the German): "Antique glider model AM-9, with electric drive.

Background: Involvement with electric flight, especially with motor gliders, has led me again and again to an old requirement of model aircraft construction, the consistent lightweight construction, if one does not limit the effort and costs of the drive to improvements want to increase. In the optimization of flight performance, whereby the quality of the drive and the gear the importance of the model is the limiting parameters, which is also where the special appeal of development and testing lies.

What could be more obvious than a throwback to the 1930s, the era of antique aircraft models, lightweight constructions designed for low descent speeds, which with their voluminous hulls also offer the necessary space for propulsion and remote control.

A visit to a model aircraft exhibition by the 'Antique-Modellflugfreunde Deutschland e.V.' in Schwäbisch Hall led me to the 'AM9', a thermal high-performance sailplane model by Artur Mantel from 1935, which was designed for the consistent use of thermal microphone was designed.

At first glance, this design met my expectations for a light motor glider. Somehow I was fascinated by the idea of equipping this seemingly fragile ancient construction with its somewhat idiosyncratic shapes with a wingspan of 220 cm but a flying weight of only 450 g with modern electronics.

The building plan was quickly obtained by the association's archivist. In the introduction to the construction description Mr Mantel describes how his model gained thermal connection from a low take-off altitude and completed long distance flights. Our natural teachers, the buzzards, also show us a similar flight technique: anticipating the beginning of the thermal separation, they skim from just tree height at the edge of the forest, turn in at the first sign of climbing, and help with centering with a few quick wing beats, then around to be carried effortlessly up into their kingdom.

I would like the flight with my models to be similar: a maneuverable thermal glider with a light electric drive and folding propeller that simulates the short flaps of the buzzard's wings! Just as nature adapts its planes in size and flight characteristics to suit their habitat, model pilots must also determine the area of operation of their model in advance.

With the light and inexpensive motorized electric model aircraft I have built so far, I have gained the following flying experiences:

1. Start on the flat, where a climbing height of 100 m is often sufficient for the initial thermal gliding flight. In weak thermal weather conditions, this flight technique requires a maneuverable model that can turn tightly without major loss of altitude, with a low wing load of 30 g/dm2 and good lateral stability..."

Update 21/10/2023: Added instructions, thanks to Axel_VPF.

Update 29/10/2023: Replaced the instructions with a clearer copy, thanks to Axel_VPF.

Quote: "Hello and good Morning Mary and Steve, I send You much better Quality Instructions (in German) for the Vintage A.M.9 Glider oz14858. This is the 4th Edition (ca.1943). Have a very nice Day!
Best Wishes from Berlin Germany,
Axel_VPF :)"

Supplementary file notes

Article (1989).
Instructions (de).

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