The Albatros D.III was the most successful in the series of Albatros biplane fighters, and helped the Germans win control of the air over the Western Front in the first part of 1917.
The Albatros biplanes were developed after the Fokker monoplanes lost their dominance in the face of improved Allied fighters. The Albatros D.I was developed early in 1916. It used a 160hp Mercedes D.III engine, more powerful than the 120hp engines used in most of its rivals. The extra power also meant that it could carry two machine guns, double the normal armament. It suffered from two flaws - the upper wing was carried too high, blocking the pilots view upwards and the inverted V centre strut obscured the pilot's view during high speed gunnery. These problems were fixed on the D.II. The upper wing was lowered, placing just above head level and allowing the pilot to look above or below the wing equally easy, and the centre strut modified so that the struts went out from the fuselage to the wings.
The Albatros D.III emerged after Albatros designers examined captured Nieuport fighters. Work on the prototype began in the late summer of 1916. The date of its first flight is unknown (many records having been lost), but it underwent static load testing in late September 1916. The D.III failed this first test and the wings had to be strengthened.
The D.III was a sesquiplane (with two wings of unequal area). In many sesquiplanes the lower wing had a significantly smaller wingspan than the upper, but in the D.III the spans remained roughly the same but the chord (distance from front to back) was much smaller on the lower wing than on the upper. Both wings had well-proportioned raked tips, based on those of the Nieuport fighters. The smaller lower wing meant that the aircraft had V-shaped inter-plane struts. The basic wing layout was very similar to that of the Nieuport 11. The smaller lower wing also greatly improved the pilot's view downwards. The wing was of all wooden construction, with twin box spars in the upper wing and a single spar in the lower wing. The two spars in the upper wing were located just behind the leading edge and in the centre of the wing, and were connected by ribs. The ailerons were built around a steel tube frame and were operated by a mid-span crank lever controlled from the lower wing.
The D.III used the same Teves and Braun flush-mounted radiator as the D.II. At first it was centrally mounted, but this had two disadvantages. First, the water pipes interfered with the pilot's view and second any damage to the radiator could spray hot water over the pilot. To solve both problems the radiator was moved to the starboard side of the centre section of the wing. A small number of D.IIIs saw service in the middle east, where a second radiator was mounted on the port side.
The compression ratio of the Mercedes D.III engine was increased in an attempt to get extra power, but the resulting few extra hp made little difference to performance.
The first production order for the D.III was placed in October 1916, and was for 400 aircraft, the largest contract yet issued in Germany. The D.III remained in production into early 1918, and was built alongside the D.V and D.Va from the summer of 1917. Albatros built the D.III until the spring of 1917, at which point it moved on to production of the D.V. The OAW factory at Schneidemühl took over production of the D.III and eventually produced more D.IIIs than Albatros.
The D.III entered service in significant numbers in the first part of 1917. Thirteen were at the front in January and 137 in March. By May 327 D.IIIs and 107 D.IIs were at the front and the D.III made up nearly half of all German fighters. The D.III remained the most important German fighter until July 1917 when the Albatros D.V and D.Va began to appear in service. The two types then operated alongside each other. The number of D.IIIs at the front peaked in November 1917 at 446 aircraft, and there were still 357 in use in March. After that numbers declined quite dramatically, halving by May and falling to only 52 by September 1918. By the end of 1917 the dominance of the Albatros was already coming to an end and it was used alongside Pfalz D.III biplanes and Fokker Triplanes. It was eventually superseded by the later Fokker biplanes.
The Albatros D.III was used by a number of German aces, including Manfred von Richtofen, Ernst Udet and Werner Voss. The pilots found it easy to fly and effective fighter, with a better rate of climb than the D.II. Some also reported it to be faster. It did suffer from one major problem - the wings weren't strong enough for combat. In January 1917 a number of aircraft had developed problems with the wing ribs and leading edges, but worse was to come. On 23 January 1917 the lower right wing of Leutnant Roland Nauck failed. Nauck managed to land safely, as did Manfred von Richthofen when a similar thing happened to him. By the end of January unmodified D.IIIs had been grounded and a reinforced lower wing was rushed to the front. Despite a series of changes the wing failures continued to occur and vigorous tests failed to reveal the reason. Even now the reason for these failures isn't known for certain, but those aircraft built by OAW and under licence in Austria didn’t suffer from the same problems.
The D.III was produced in Austria by the Osterreichische Flugzeugfabrik AG. These aircraft were powered by Austro-Daimler engines providing between 185 and 225hp. The Austrians gained a licence to build the Albatros D.II after its introduction on the Western Front. The first contract, in December 1916, was for the production of 16 D.IIs and 34 D.IIIs. The Austrians produced a modified D.III, with a stronger wing and airframe, thus avoiding the wing failures of the German D.III and allowing Oeffag to install more powerful engines later in the war. The Austrian machines reached the Italian front in June 1917, and gave the Austrians an aircraft equal to their Allied opponents. The Austrians continued to improve the basic D.III during the war. Series 153 aircraft had a 200hp Daimler engine and most had a rounded nose. Top speed rose to 121mph from the 112mph of the first Austrian aircraft. This was followed by the Series 254 version, which used a 225hp Daimler engine and that entered production and service during 1918.
Engine: Mercedes D.IIIa
Span: 29ft 6in (upper), 28ft 10in (lower)
Length: 24ft 0.5in
Height: 9ft 6in
Empty weight: 1,484lb (Albatros), 1,464lb (OAW)
Loaded weight: 2,002lb (Albatros), 2,018lb (OAW)
Max speed: 102mph
Armament: Two synchronised 7.92mm LMG 08/15 Spandau machine guns