International Scale Modeller

https://en.wikipedia.org/wiki/Albatros_D.V wrote:
Design and development
In April 1917, Albatros received an order from the Idflieg (Inspektion der Fliegertruppen) for an improved version of the D.III. The resulting D.V prototype flew later that month. The D.V closely resembled the D.III and used the same 127 kW (170 hp) Mercedes D.IIIa engine. The most notable difference was a new, fully elliptical cross-section fuselage which was 32 kg (71 lb) lighter than the partially flat-sided fuselage of the earlier D.I through D.III designs. The new elliptical cross-section required an additional longeron on each side of the fuselage and the fin, rudder and tailplane initially remained unchanged from the D.III. The prototype D.V retained the standard rudder of the Johannisthal-built D.III but production examples used the enlarged rudder featured on D.IIIs built by Ostdeutsche Albatros Werke (OAW). The D.V also featured a larger spinner and ventral fin.

Compared to the D.III, the upper wing of the D.V was 121 mm (4.75 in) closer to the fuselage, while the lower wings attached to the fuselage without a fairing. The D.V wings were almost identical to those of the standard D.III, which had adopted a sesquiplane wing arrangement broadly similar to the French Nieuport 11. The only significant difference between wings of the D.III and D.V was a revised routing of the aileron cables that placed them entirely within the upper wing. Idflieg conducted structural tests on the fuselage but not the wings of the D.V.

Early examples of the D.V featured a large headrest, which was usually removed in service because it interfered with the pilot's field of view. The headrest was deleted from the second production batch. Aircraft deployed in Palestine used two wing radiators, to cope with the warmer climate.

Idflieg issued production contracts for 200 D.V aircraft in April 1917, followed by additional orders of 400 in May and 300 in July. Initial production of the D.V was exclusively undertaken by the Johannisthal factory, while the Schneidemühl factory produced the D.III through the remainder of 1917.

Operational history
The D.V entered service in May 1917 and structural failures of the lower wing immediately occurred. In 2009, Guttman wrote that "Within the month Idflieg was doing belated stress testing and concluding, to its dismay, that the D V’s sesquiplane wing layout was even more vulnerable than that of its predecessor". The outboard sections of the D.V upper wing also suffered failures, requiring additional wire bracing, and the fuselage sometimes cracked during rough landings.

Against these problems, the D.V offered very little improvement in performance. Front line pilots were considerably dismayed and many preferred the older D.III; Manfred von Richthofen was particularly critical of the new aircraft. In a July 1917 letter, he described the D.V as "so obsolete and so ridiculously inferior to the English that one can't do anything with this aircraft". British tests of a captured D.V revealed that the aircraft was slow to maneuver, heavy on the controls and tiring to fly.

Albatros responded with the D.Va, which featured stronger wing spars, heavier wing ribs and a reinforced fuselage. The modified D.Va was 23 kg (51 lb) heavier than the D.III but the structural problems were not entirely cured. Use of the high-compression 130 kW (180 hp) Mercedes D.IIIaü engine offset the increased weight of the D.Va. The D.Va also reverted to the D.III aileron cable linkage, running outwards through the lower wing, then upwards to the ailerons to provide a more positive control response. The wings of the D.III and D.Va were interchangeable. To further strengthen the wing, the D.Va added a small diagonal brace connecting the forward interplane strut to the leading edge of the lower wing; the brace was also retrofitted to some D.Vs.

Idflieg placed orders for 262 D.Va aircraft in August 1917, followed by orders for another 250 in September and 550 in October. Ostdeutsche Albatros Werke, which had been engaged in production of the D.III, received orders for 600 D.Va aircraft in October. Deliveries of the D.Va commenced in October 1917. The structural problems of the Fokker Dr.I and the mediocre performance of the Pfalz D.III left the Luftstreitkräfte with no alternative to the D.Va until the Fokker D.VII entered service in mid-1918. Production of the D.Va ceased in April 1918. In May 1918, 131 D.V and 928 D.Va aircraft were in service on the Western Front; the numbers declined as the Fokker D.VII and other types replaced the Albatros in the final months of the war. By 31 August, fewer than 400 Albatros fighters of all types remained at the front but they continued in service until the Armistice.

General characteristics
Crew: 1
Length: 7.33 m (24 ft 1 in)
Wingspan: 9.05 m (29 ft 8 in)
Height: 2.7 m (8 ft 10 in)
Wing area: 21.2 m2 (228 sq ft)
Empty weight: 687 kg (1,515 lb)
Gross weight: 937 kg (2,066 lb)
Powerplant: 1 × Mercedes D.IIIaü piston engine, 150 kW (200 hp)
Propellers: 2-bladed wooden propeller

Performance
Maximum speed: 186 km/h (116 mph; 100 kn)
Endurance: 350 km
Service ceiling: 5,700 m (18,700 ft)
Rate of climb: 4.17 m/s (821 ft/min)
Time to altitude: 1,000 m (3,281 ft) in 4 minutes
Armament
Guns: 2 × 7.92 mm (0.312 in) LMG 08/15 machine guns