The 1930s saw the development of certain light-weight and low-power aviation engines that were intended for small craft and that made Volksflugzeug-type planes feasible both from the low cost as well as from a technical perspective.

The Zündapp 9-090, also known as Zündapp Z 90, was a small aeronautical piston engine built by the Zündapp company.
Its successor, the Zündapp 9-092, was a more powerful four-cylinder version developed in 1938.
Both engines were designed by Ernst Schmidt.
 Zündapp 9–092 production was terminated in 1940 when about 200 units had been built.
Although planes fitted with these engines had broken several records in their class, precedence was given to the production of military plane engines in an industrial scale.

The DKW company, founded and led by Danish entrepreneur Jørgen Skafte Rasmussen also developed a small 20 hp (15 kW) aviation engine.
It was used for the DKW Erla Me 5, a low-cost one-seat low wing Volksflugzeug.
Conceived by engineer Franz Xaver Mehr, a small number of Me 5 were built in series in 1933 before the production faced difficulties.
In 1934, DKW chief Rasmussen was able to convince the Gauleiter of Saxony, the Reichsstatthalter (representative of the Third Reich) in the region, to become interested in the project.
As a result, the Erla Maschinenwerk G.m.b.
H. company was founded in Leipzig and took over production and projects.
Rasmussen, nevertheless, left after a few years, when industrial production was shifted to military aircraft.

The Hirth HM 515 was another low-cost piston engine for small aircraft built by the German aviation company Hirth.
It was a little four-cylinder OHV piston engine first presented in 1938.
After several tests, only a small number of units were built from 1940 onwards, owing to the lack of demand for small, less-powerful engines during the war years.
It would have been used in  Volksflugzeug-type planes such as the Bücker Bü 180, Fieseler Fi 253 Spatz, Haller Ha 22 and Ha 23, as well as the Klemm Kl 105, Pause Mücke, Siebel Si 202 and Gotha Go 150.

Köller was another company building small engines giving 18 hp (13 kW) and 18.5 hp (14 kW).
The little Gruse BO 15/1 was a Volksflugzeug project equipped with a Köller M3 18 hp (13 kW) engine driving a pusher propeller.
It was a light single seater built by the August Gruse Maschinenfabrik in 1933.
Following the scant interest displayed by Nazi authorities, only one prototype was built.
The 1930s saw the development of certain light-weight and low-power aviation engines that were intended for small craft and that made Volksflugzeug-type planes feasible both from the low cost as well as from a technical perspective.
The Zündapp 9-090, also known as Zündapp Z 90, was a small aeronautical piston engine built by the Zündapp company. Its successor, the Zündapp 9-092, was a more powerful four-cylinder version developed in 1938. Both engines were designed by Ernst Schmidt.  Zündapp 9–092 production was terminated in 1940 when about 200 units had been built. Although planes fitted with these engines had broken several records in their class, precedence was given to the production of military plane engines in an industrial scale.
The DKW company, founded and led by Danish entrepreneur Jørgen Skafte Rasmussen also developed a small 20 hp (15 kW) aviation engine. It was used for the DKW Erla Me 5, a low-cost one-seat low wing Volksflugzeug. Conceived by engineer Franz Xaver Mehr, a small number of Me 5 were built in series in 1933 before the production faced difficulties. In 1934, DKW chief Rasmussen was able to convince the Gauleiter of Saxony, the Reichsstatthalter (representative of the Third Reich) in the region, to become interested in the project. As a result, the Erla Maschinenwerk G.m.b.H. company was founded in Leipzig and took over production and projects. Rasmussen, nevertheless, left after a few years, when industrial production was shifted to military aircraft.
The Hirth HM 515 was another low-cost piston engine for small aircraft built by the German aviation company Hirth. It was a little four-cylinder OHV piston engine first presented in 1938. After several tests, only a small number of units were built from 1940 onwards, owing to the lack of demand for small, less-powerful engines during the war years. It would have been used in  Volksflugzeug-type planes such as the Bücker Bü 180, Fieseler Fi 253 Spatz, Haller Ha 22 and Ha 23, as well as the Klemm Kl 105, Pause Mücke, Siebel Si 202 and Gotha Go 150.
Köller was another company building small engines giving 18 hp (13 kW) and 18.5 hp (14 kW). The little Gruse BO 15/1 was a Volksflugzeug project equipped with a Köller M3 18 hp (13 kW) engine driving a pusher propeller. It was a light single seater built by the August Gruse Maschinenfabrik in 1933. Following the scant interest displayed by Nazi authorities, only one prototype was built.
Volksflugzeug