Lyonaeec 22001 — Fokker Dr.I Triplane Rubber-Band Powered Model missing winding unit

Manufacturer: Lyonaeec

Product: 22001 / 22001(E)

Barcode: 4892818220017

Subject: Fokker Dr.I Triplane

Historical aircraft: 1917

Type: Rubber-band-powered flying model

Scale: Not specified

Material: Lightweight model-aircraft construction; exact material breakdown not reliably documented

Status: Discontinued/older production
Kit contents

The surviving listings do not provide a reliable parts count, so I would not invent one.

The product is a rubber-band-powered model, meaning its principal components are intended to form a lightweight flying airframe with:

three wing surfaces;

fuselage;

tail surfaces;

undercarriage/landing arrangement;

propeller;

rubber motor;

associated flying-model fittings;

assembly components.

The purpose is to reproduce the general appearance and flying concept of the Fokker Dr.I while using a simple rubber-powered propulsion system.

The lack of a manufacturer-published scale is important. I would not calculate a scale from photographs, because flying models are frequently simplified or enlarged relative to true scale in order to obtain acceptable flight characteristics.
Lyonaeec

Lyonaeec appears in surviving hobby and catalogue records primarily as a producer of lightweight flying aircraft models, including rubber-powered historical aircraft and other model-aircraft subjects.

The 22001 belongs to a family that includes several numbered Lyonaeec aircraft products. The barcode catalogue places 22001 alongside 22002, 22003(E), 22004 and 22005(E), while other Lyonaeec ranges include 330xx, 88010 and 950xx products.

This helps establish that 22001 was part of a series of flying/model-aircraft products, rather than an isolated plastic-kit release.
The real aircraft — Fokker Dr.I

The aircraft represented is the famous Fokker Dr.I Dreidecker, or Fokker Triplane, one of the most recognisable fighters of the First World War.

It was developed by Fokker-Flugzeugwerke in Germany, with the design work principally associated with Reinhold Platz.

The aircraft was a compact single-seat triplane designed primarily for air combat.

Its three wings gave it a very large lifting area for its short wingspan, producing excellent manoeuvrability and climb performance.

The trade-off was aerodynamic drag and relatively modest maximum speed compared with contemporary Allied fighters.

The first prototype flew in 1917, with operational examples reaching the Western Front later that year. Sources differ slightly on the precise first-flight date, but the production aircraft's development and service period are firmly placed in 1917–1918.
Why Fokker built a triplane

The Dr.I was developed during a period when the British Sopwith Triplane had attracted considerable attention.

The Sopwith's excellent climb and manoeuvrability encouraged several German manufacturers to investigate three-wing designs.

The Fokker solution was not simply a direct copy of the Sopwith.

Reinhold Platz developed the German triplane with a distinctive welded-steel-tube fuselage and cantilever-style wing structure.

One of the major advantages was that the aircraft could achieve a large wing area without requiring an exceptionally long wingspan.

The result was a compact fighter with a high lift-to-weight ratio.
The three-wing arrangement

The Dr.I had:

upper wing: approximately 7.19 m span;

middle wing: approximately 6.23 m span;

lower wing: approximately 5.73 m span.

The progressively shorter lower wings gave the aircraft its distinctive tapered planform when viewed from above.

The overall wing area was approximately 18.7 m².

The arrangement produced excellent lift and manoeuvrability.

It also provided the pilot with good upward visibility.

The disadvantage was drag.

The aircraft could turn and climb exceptionally well, but faster contemporary fighters could often disengage simply by using their superior speed.
Engine

The standard production Dr.I was powered by the Oberursel Ur.II, a nine-cylinder air-cooled rotary engine producing approximately 110 hp.

The Oberursel was closely related to the French Le Rhône rotary engine, and German production included engines derived from that design.

Some experimental and individual aircraft used other rotary engines, including:

Le Rhône engines;

Siemens-Halske engines;

Goebel engines.

These were exceptions rather than the standard production arrangement.
Rotary-engine characteristics

The Dr.I's rotary engine was fundamentally different from a modern radial.

The cylinders rotated around the crankshaft along with the crankcase.

This provided excellent cooling and a favourable power-to-weight ratio, but it also produced substantial gyroscopic effects.

Pilots had to account for these effects during manoeuvres.

The engine also consumed large amounts of castor oil.

Because early rotary engines exhausted much of their lubricant overboard, pilots and aircraft became coated with oil during operation.
Armament

The production Dr.I carried two synchronised 7.92 mm Spandau machine guns.

They were mounted in the upper fuselage ahead of the cockpit and fired through the propeller arc using interrupter/synchronisation equipment.

This gave the pilot a concentrated forward-firing armament.

The weapons were relatively light by later standards but were entirely conventional for a 1917 fighter.
Performance

Representative production Dr.I specifications include:

Crew: 1

Engine: Oberursel Ur.II

Power: 110 hp

Length: approximately 5.77 m

Upper wingspan: approximately 7.19 m

Height: approximately 2.95 m

Wing area: approximately 18.7 m²

Empty weight: approximately 400 kg

Loaded weight: approximately 585–586 kg

Maximum speed: roughly 165 km/h, depending on source and test conditions

Ceiling: approximately 6,000–6,500 m

Endurance: approximately 1½ hours.

The exact performance figures vary between surviving German test data and later published specifications, so these should be treated as representative rather than absolute.