Roden PKZ-2 Austro-Hungarian Helicopter — 1:72

Manufacturer and kit history

Roden is a Ukrainian model-kit manufacturer particularly recognised for unusual subjects from the First World War and early aviation. Kit 008 is one of its early and particularly distinctive aviation subjects.

The PKZ-2 is an unusual choice for a plastic model because it was not a conventional aircraft: it was an experimental tethered rotary-wing machine developed in Austria-Hungary during the closing stages of the First World War.

The model is supplied as an unassembled and unpainted plastic kit. A current product description lists a single frame of parts, decals, a display stand, painting instructions and detailed instructions in Russian and English.

Kit contents

The Roden 008 includes the main components needed to reproduce the unusual PKZ-2:

• Main circular/central airframe structure

• Rotor assembly

• Engine components

• Propulsion system

• Pilot/control position

• Landing/support structure

• Tethering-related components

• Decals

• Display stand

• Painting guide

• Assembly instructions

The finished model is approximately 80–83 mm long, depending on how dimensions are measured.

Because of the aircraft's unusual construction, this is quite a different modelling project from a conventional First World War biplane.

The full-size PKZ-2

The PKZ-2 was an experimental Austro-Hungarian rotary-wing aircraft developed during 1918, near the end of the First World War.

The designation PKZ is associated with the development work of Petróczy, Kármán and Žurovec. The project sought to create a machine capable of providing a stable observation platform without relying on conventional fixed-wing flight.

The basic concept was very different from a modern helicopter.

Rather than carrying a large horizontal tail rotor and flying freely, the PKZ-2 was essentially a tethered vertical-lift platform.

Design

The aircraft used a large central rotor mounted above a framework.

Its powerplant arrangement was unusual because the designers used multiple engines to provide power to the rotor system.

The machine was intended to rise vertically while remaining connected to the ground by cables.

This tethering arrangement was intended to prevent the experimental aircraft from simply drifting away and also allowed it to serve as a stationary observation platform.

Engines

The PKZ-2 initially experienced problems with its powerplant.

The designers eventually used two Austro-Daimler 100 hp engines, arranged to drive the lifting system.

The engines were mounted in the central structure and transmitted power to the rotor.

The combined output provided approximately 200 hp.

The relatively low power-to-weight ratio was one of the fundamental limitations of the project.

Unmanned testing

One of the most interesting characteristics of the PKZ-2 was that its test flights were conducted without a pilot aboard.

Contemporary and later references generally state that it completed approximately 36 unmanned test flights.

It reached an altitude of approximately 50 metres during testing.

This makes the PKZ-2 an important step in the development of practical rotary-wing flight, even though it never became an operational aircraft.

Why it was developed

The Austro-Hungarian military was interested in the possibility of a vertical-lift observation platform.

A machine that could rise above obstacles and remain relatively stationary could potentially provide:

• Artillery observation

• Battlefield reconnaissance

• Observation of enemy positions

• Communications support

• Naval/coastal observation

The ability to operate without a runway was particularly attractive.

However, the technology required to make such an aircraft practical was still in its infancy.

Problems with the design

The PKZ-2 suffered from numerous technical problems.

The engines and transmission system were difficult to manage, while the aircraft's structure and rotor system created substantial vibration and stability problems.

The machine was also extremely dependent on its ground tethering arrangement.

These difficulties prevented the aircraft from becoming a practical military helicopter.

A current Roden product description notes that the PKZ-2 was not accepted for armed service because of its numerous technical problems.

End of the project

The collapse of the Austro-Hungarian Empire in 1918 effectively ended the military development programme.

The PKZ-2 therefore remained an experimental machine rather than becoming an operational observation aircraft.

Nevertheless, the project demonstrated that powered vertical flight was technically possible and contributed to the wider development of helicopter technology.

Historical significance

The PKZ-2 is particularly interesting because it belongs to the period when engineers were beginning to move from experimental rotary-wing machines toward practical helicopters.

It should not be confused with a modern helicopter. Its tethered configuration, exposed framework and unusual engine arrangement were characteristic of the experimental technology of the period.

The project is nevertheless an important part of the history of vertical flight.

The machine's reported 36 unmanned test flights and approximately 50 m altitude make it one of the more significant Austro-Hungarian rotary-wing experiments of the First World War.