O.Thetford, P.Gray German Aircraft of the First World War (Putnam)

Oertz W 5
   Engine, 240 h.p. Maybach Mb IV. Span, 180 m. (59 ft. 0 3/4 in.). Length, 11.7 m. (38 ft. 4 5/8 in.). Area, 77 sq.m. (832 sq.ft.). Weights: Empty, 2,018 kg. (4,440 lb.). Loaded, 2,638 kg. (5,804 lb.). Speed, 120-125 km.hr. (75-78.125 m.p.h.). Climb, 1,500 m. (4,920 ft.) in 22 min.

Форум Breguet's Aircraft Challenge

The Oertz W 5 is one type in the long flying boat series of Oertz. Flying boats at Oertz started when they made the hull of the Melli Beese designed flying boat just before the outbreak of the war. A lot of characteristics of the Melli Beese Flugboot were transferred to the Oertz flying boats. The prime characteristic was the place of the engine in the fuselage driving the pusher propeller via a chain drive. The compartment of the engine in the fuselage was waterproof (double walls).
   The Oertz W 5 was one of the heavier Oertz flying boars, being powered with a 240 hp Maybach engine. Wings were 3-bay, equal span. In 1915 five were built for the Deutsche Marine (No. 276-280).

Журнал Flight

Flight, October 9, 1919.

THE OERTZ FLYING BOATS

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   "It was not long before a demand arose for larger and more powerful boats, and the Oertz Works received an order for a series of flying boats, which were to be fitted with 260 h.p. Argus engines. Delivery of these engines was much delayed, and when they were available they proved to have exceeded the estimated weight to such an extent that it was quite out of the question to fit them in the Oertz boats. It was, therefore, decided to fit, instead, the 240 h.p. Maybach airship motors, which were at that time quite new. This was done, and in the autumn of 1915 the first of these boats could be delivered. In spite of the fact that the boats were really too large for the engines' power, which was lower than that for which they were designed, and that the engines were heavier than had been the estimated weight of the Argus engines, the boats were able to pass their acceptance tests. One of these boats is shown in Fig. 5.
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