Arado SD.III

Good Saturday morning. Todays' post is dedicated to the third Arado fighter prototype, the Arado SD.III.

The Arado SD.III was a biplane fighter prototype that was built in Germany during the very lates 1920s. The development was made in parallel with the SD.II and employed a similar airframe.

Unlike the SD.II which was powered by a geared engine, this one was powered by a 510hp Siemens und Halske-built Jupiter VI engine which featured a smaller-diameter and a two-bladed propeller. In order to adapt the engine to the fuselage, the shape of the forward fuselage was revised and shorter underacarriage with more rake was fitted. It was armed with two 7,92mm 08/15 machine guns, just like the SD.II.

It was evaluated in Staaken, Rechlin and Lipetsk and, despite it was judged unsuitable for mass production, it served as the basis in order to design and develop the following Arado Ar.64 and Ar.65.

Sources:
1. https://en.wikipedia.org/wiki/Arado_SD_III
2. Salamander Books - The Complete Book of Fighters.

Arado SD.II

Today we write about another Arado fighter prototype which, unfortunately, there aren't any known blueprints, so this post has not any drawing.

The Arado SD.II was a German biplane fighter developed in 1929. It was meant to equip the German clandestine air force that was being formed.

Despite sharing the same basic outlines from the previous SD.I, it was an all-new design, larger and heavier. The wings were less staggered and they were braced with conventional wires. Both the landing gear and the tail of the airplane were considerably stronger.

It was powered by a 530hp Bristol Jupiter nine-cylinder radial engine built by Siemens und Halske which, with a three bladed propeller, it required a high angle of attack on the ground. It was also armed with a pair of 7,92mm 08/15 machine guns.

It proved to be difficult to fly and was discarded in favour of the Heinkel HD.37. However, this one, together with the Arado SD.III set the basis for the Arado Ar.64, which was the company's first mass produced fighter.

The only known pic of the Arado SD.II

Sources:
1. https://en.wikipedia.org/wiki/Arado_SD_II
2. Salamander Books - The Complete Book of Fighters

Arado SD.I

Good morning, we are back in Germany, in order to cover this early German fighter, and we're going to stay in that country for quite some time.

The Arado SD.I was the first biplane fighter developed by the Arado Flugzeugwerke in Warnemünde. It was designed by the engineer Walter Rethel, who owed much experience gained with Fokker.

The SD.I was a relatively small mixed-construction sesquiplane. The fuselage was of welded steel tubing with light alloy skinning to the cockpit firewall and fabric aft. Wings were made out of wood with plywood skinning and the ailerons were placed in the upper wings only. It had V-type struts and lacked conventional flying wires, which apparently was something very typical from Fokker.

It was powered by a 425hp nine-cylinder Gnome-Rhône Jupiter air-cooled radial engine and was armed with two synchronised 7,92mm 08/15 machine guns.
It was the first fighter to be object of a contract from the Reichswehrministerium (ministry of war) and its' development was totally clandestine. The first two prototypes were tested in Lipetsk, USSR on 11th October 1927 and the performance prooved to be poor specially at low speeds. Given those poor characteristics, the development was halted in order to favour a complete new design, the Arado SD.II

Sources:
1. https://en.wikipedia.org/wiki/Arado_SD_I
2. Salamander Books - The complete book of fighters

Albatros L.77v

Nice new week for all our readers. This time we bring you another clandestine Albatros fighter.

The Albatros L.77v was a German two-seat reconnaissance-fighter biplane manufactured under license for Albatros Flugzeugwerke by the Ernst Heinkel Flugzeugwerke.
They were completed in 1928 and were heavily based on the previous L.76 design which was an unarmed two-seater reconnaissance biplane.

It was powered by a 600hp BMW VI water cooled V12 engine, and like its predecessor it was covered by a fabric-covered welded-steel fuselage and wooden dual-spar wings with plywood skin supported by N-type struts.
It was armed by a pair 7,92mm forward-firing machine-guns and complemented by another ring-mounted one in the observer position.

The airplanes tested in Germany were flown unarmed due to the restrictions of the Versailles Treaty but the ones used in Lipetsk, USSR, were flown with armament, which some sources claim that at least one airplane was flow with a free-mounted 20mm cannon and other claim that it could carry 2 50Kg bombs.
Anyway, one of the L.77v was destroyed while performing flying tests in March 1929, while the rest were sent to Lipetsk for armament evaluation. In December 1929 they were taken back to the Staaken test centre, in Berlin and were written-off in October 1931.

Sources:
1. https://en.wikipedia.org/wiki/Albatros_L_77v
2. Salamander Books - The Complete Book of Fighters
3. http://www.aviastar.org/air/germany/albatros_l-77v.php

Albatros L.65/Memel A.F.G. 1

We have included this flag because, as Germany was forbidden to own an air force/air corps, every warplane manufactured (clandestinely) was, organically dependant of the Reichswehr, the armed forces of the German Republic.

The Albatros L.65, AKA Memel A.F.G.1 was a German/Lithuanian two-seat reconnaissance fighter airplane of the mid-1920s.

Under the restrictions of the Treaty of Versailles, Germany couldn't have an air force or air corps, so, in order to evade those restrictions, the Albatros Flugzeugwerke stablished a subsidiay company in Lithuania called Allgemeine Flug-Gesellschaft Memel located in the Lithuanian city of Memel, hence the secondary name of this airplane.

Two prototypes were built and both of them were made out of wood and were covered in plywood skin in an staggered biplane configuration. Wings were joinced by interplane I-struts of broad aerofoil cross-section.
The first prototype was powered by a 450hp 12-cylinder Napier Lion engine, while the second one used the same up-powered version of the same engine, which had a power of 565hp.

The first prototype was demonstrated to General Kraucevicius, who was the chief of the Lithuanian Air Force at the time, as the airplane that would be the first native Lithuanian aircraft, but it wasn't followed by any acquisition order from the Lithuanian government.
The second prototype was evaluated by the Reichswehr, in order to equip the clandestine flying school located in Lipetsk, USSR, but the better Heinkel HD.17 was choosen.

 Sources:
1. https://en.wikipedia.org/wiki/Albatros_L_65
2. Salamander Books - The Complete book of fighters
3. http://1000aircraftphotos.com/Contributions/McBrideBill/11500.htm