Rohrbach Ro III
Rohrbach Ro III | |
---|---|
A Rodra in Turkish Naval markings, November 1930 | |
Role | Flying boat airliner or long-range reconnaissance aircraft |
National origin | Germany |
Manufacturer | Rohrbach Metall-Flugzeugbau |
First flight | c.1924 |
Number built | at least six |
Developed from | Rohrbach Ro II |
The Rohrbach Ro III was a twin-engined, all-metal
.Design and development
Dr.-Ing. Adolf Rohrbach gained his initial experience with light-alloy structures for aircraft with
During its construction the Ro III was known as the Ro II series III, indicating its close similarity to its predecessor. The most obvious difference was a sharp bow to improve seaworthiness. It was advertised in two forms, either as a ten passenger airliner or a long range reconnaissance aircraft.[1]
The Ro III had a
The Ro III was powered by a pair of 270 kW (360 hp) water-cooled
The hull, like the rest of the aircraft, was all-metal and rectangular, with flat sides and top. Its planing bottom was also flat, with two steps. Stability on the water was provided by long, stepless floats on each side, strut-mounted from the wings a little outside the engines and braced to the fuselage with a parallel pair of horizontal struts. The hull tapered in plan to the tail, where the empennage was again rectangular, with a broad
There was an open cockpit just ahead of the propeller discs. In military reconnaissance configuration it had a crew of three. Like some other Rohrbach flying boats, the Ro III carried a pair of masts and sails, to be used if the aircraft was forced to put down at sea without engine power.[1]
In the first half of 1926, Rohrbach introduced the Ro IIIa Rodra.[1] The new variant was more powerful, with two 340 kW (450 hp) Lorraine 12E Courlis W12 water-cooled engines in shorter and more streamlined cowlings, with their honeycomb radiators on the wing underside below them. The wing was mounted on top of the fuselage, its span reduced by 1.45 m (4 ft 9 in), and the ailerons were no longer compensated.[3]
Designed only for the long range reconnaissance bomber role it had side-by-side dual controls and two gun positions, one in the nose and the other closer to the tail than the wing, both equipped with twin machine guns.[3] The nose position was also used for observation and bomb-aiming; the bombs were mounted underwing beyond the floats.[1]
Operational history
Four Ro IIIs were delivered to Japan in 1925 as Rohrbach R-1s. Two of these had their original 270 kW (360 hp) Eagles engines replaced by 340 kW (450 hp) Hispano-Suiza or Lorraine 12E Courlis engines, and were re-designated R-2 and R-3. At least one Ro III appeared on the Japanese civil register as J-BHAE and was used by the Japan Airline Co. Mitsubishi bought a licence to build Rohrbach aircraft in Japan but it seems not to have been used.
Two Rodras were sold to the Turkish Navy and based at Smyrna. After four years of operation, they were given a lengthy examination by the German aviation authorities, who found them in good order and with no safety problems.[1]
Two Rodras were bought by and tested by the RAF at Martelsham Heath.[4][dubious ]
Variants
- Ro III
- 29 m (95 ft 2 in) span, 270 kW (360 hp) Rolls-Royce Eagle IXengines initially. Four sold to Japan where two were re-engined.
- Ro IIIa Rodra
- As described, two sold to Turkish Navy.
Specifications (Ro IIIa Rodra)
Data from Les Ailes, March 1927[3] except where noted
General characteristics
- Crew: Three[1]
- Length: 17.20 m (56 ft 5 in)
- Wingspan: 27.55 m (90 ft 5 in)
- Height: 6.0 m (19 ft 8 in)
- Wing area: 73.40 m2 (790.1 sq ft)
- Aspect ratio: 10.3
- Empty weight: 3,900 kg (8,598 lb)
- Gross weight: 5,650 kg (12,456 lb)
- Powerplant: 2 × Lorraine 12E Courlis water-cooled W12, 340 kW (450 hp) each
- Propellers: 2-bladed
Performance
- Maximum speed: 195 km/h (121 mph, 105 kn)
- Endurance: 3 hr
- Service ceiling: 3,000 m (9,800 ft)
- Time to altitude: 17 min to 2,000 m (6,600 ft)
- Touchdown speed: 100 km/h (62 mph; 54 kn)
Armament
- Guns: Pairs of machine guns in nose and dorsal positions. total of 2,000 rounds.
- Bombs: 1,196 kg (2,637 lb)
References
- ^ ISBN 3-87943-565-0.
- ^ "Rohrbach Ro". Retrieved 4 November 2017.
- ^ a b c Serryer, J. (31 March 1927). "L'Hydravion Rohrbach "Rodra"". Les Ailes (302): 3–4.
- ^ Conradis, Heinz (1960). Design for Flight (The Kurt Tank Story). London: Mcdonald & Co.