Dornier Do 24

The Dornier Do 24 was designed to meet a Royal Netherlands Navy requirement for a replacement of the Dornier Wals being used in the Dutch East Indies, with the Netherlands government signing a contract for six Dornier Do 24s on 3 August 1936. Two more prototypes were built for the German navy to be evaluated against the Blohm & Voss BV 138.[1]

The Do 24 was an all-metal parasol monoplane with a broad-beamed hull and stabilising sponsons. Twin tails were mounted on the upswept rear of the hull, while three wing-mounted tractor configuration engines powered the aircraft. Fuel was carried in tanks in the sponsons and the wing centre section.[2][3] Up to 1,200 kg (2,600 lb) of bombs could be carried under the aircraft's wings, while defensive armament consisted of three gun turrets, one each in nose, dorsal and tail positions. In early aircraft the turrets were each fitted with a machine gun but later aircraft carried a 20 mm cannon in the dorsal turret.[2][4]

Do 24 V3, the first of the Dutch boats, took off from Lake Constance on 3 July 1937, with the second Dutch boat, Do 24 V4 following soon after.[2] As the Dutch required that their flying boats use the same engines as the Martin 139 bombers in use in the Dutch East Indies, they were fitted with 661 kW (887 hp) Wright R-1820-F52 Cyclone radial engines. Test results were good, with the new flying boat proving capable of operating from extremely rough open seas and the Dutch placed an order for a further 12 Do 24s on 22 July 1937.[2] Do 24 V1, the first of the two aircraft for Germany, powered by three 600 hp (450 kW) Junkers Jumo 205C diesel engines, flew on 10 January 1938 but after evaluation, the two German boats were returned to Dornier for storage.[5]

The Netherlands was enthusiastic about the new flying boat and planned to purchase as many as 90. Of these, 30 were to be built by Dornier (with all but the first two prototypes assembled by Dornier's Swiss subsidiary based at Altenrhein). The remaining aircraft were to be built under licence in the Netherlands by Aviolanda at Papendrecht. Of these aircraft, all but one of the German and Swiss built aircraft and the first seven Aviolanda-built aircraft were to be Do 24K-1s, powered by the original R-1820-F52 engines, while the remaining aircraft were to be Do 24K-2s, with more powerful 820 kW (1,100 hp) R-1820-G102 engines and more fuel.[5]

Only 25 aircraft had been built on the Aviolanda assembly line before the German occupation. The Luftwaffe were interested in the completed and partially completed aircraft. The Dutch production line continued to produce aircraft under German control. 11 airframes were completed with Dutch-bought Wright Cyclone engines but later models used the BMW Bramo 323R-2. A further 159 Do 24s were built in the Netherlands during the occupation, most under the designation Do 24T-1.

Another production line for the Do 24 was established in the old CAMS factory at Sartrouville, France, during the German occupation. This line was operated by SNCAN and was able to produce another 48 Do 24s. After the liberation, this facility produced a further 40 Do 24s, which served with the French Navy until 1952.

A Luftwaffe Do.24 in Romania, 1941

Thirty-seven Dutch- and German-built Do 24s had been sent to the East Indies by the time of the German occupation of the Netherlands in June 1940. Until the outbreak of war, these aircraft would have flown the tri-color roundel. Later, to avoid confusion with British or French roundels, Dutch aircraft flew a black-bordered orange triangle insignia. A Dutch Dornier Do 24 is credited with sinking the Japanese destroyer Shinonome on December 17, 1941 while the ship was escorting an invasion fleet to Miri in British Borneo.[6] On 10 January 1942 a Dutch Dornier Do 24K spotted a Japanese invasion fleet heading for Tarakan Island in Dutch Borneo, giving adequate warning so that all oil installations could be destroyed before the Japanese arrived.[7] After the Japanese invasion of the Netherlands East Indies, six surviving Do 24s were transferred to the Royal Australian Air Force in February 1942. They served in the RAAF through most of 1944 as transports in New Guinea.

On 31 October 1944, a German Do 24 (CM+RY of Seenotgruppe 81) made a forced landing in neutral Sweden, was impounded and eventually bought, and remained in Swedish service until 1952.

In 1944, 12 Dutch-built Do 24s were delivered to Spain with the understanding that they would assist downed airmen of both sides. After the war, a few French-built Do 24s also found their way to Spain. Spanish Do 24s were operational at least until 1967, and possibly later. In 1971, one of the last flying Spanish Do 24s was returned to the Dornier facility on Lake Constance for permanent display.

The restored and re-engined Do.24 ATT with Pratt & Whitney PT6A-45 turboprop engines

Do 24K-1

Swiss production & Dutch license production aircraft, 36 built.

Do 24K-2

Dutch licence production powered by three 746 kW (1,000 hp) Wright R-1820-G102 engines. 1 built.

Do 24N-1

Dutch-built Do.24K-2s completed for Luftwaffe for air-sea rescue powered by three 746 kW (1,000 hp) Wright R-1820-G102 engines, 11 conversions.

Do 24T-1

French production, 48 built

Do 24T-1

Dutch production for the Luftwaffe powered by three BMW Bramo 323R-2 engines, 159 built (including T-2 and T-3).

Do 24T-2

Do 24T-1 with minor changes.

Do 24T-3

Do 24T-1 with minor changes.

Do 24 ATT

Post-war restoration/amphibian conversion with three Pratt & Whitney Canada PT6A-45 turboprop engines, one converted.

Do 318

One Do.24T modified in 1944 with a boundary-layer control system.

 Australia

• Royal Australian Air Force

 France

• French Navy (Postwar)

 Nazi Germany

• Luftwaffe

 Netherlands

• Royal Netherlands Navy
  • Netherlands Naval Aviation Service[8]

 Norway

• Royal Norwegian Air Force (Postwar)

 Soviet Union

• Polar Aviation[9]

 Spain

• Spanish Air Force

 Sweden

• Swedish Air Force

Dornier Do 24 on display

Australia

• Unknown – Do 24 K-1 forward fuselage on static display at the Lake Boga Flying Boat Museum in Lake Boga, Victoria.[10] It was previously used as a private boat in Echuca, Victoria.[11]

France

• 1101 – Do 24 T-3 forward fuselage on static display at the Musée de l'Hydraviation in Biscarrosse, Nouvelle-Aquitaine.[12]

Germany

• 5291/5345 – Do 24 T-3 on static display at the Flugwerft Schleißheim branch of the Deutsches Museum in Oberschleißheim, Bavaria.[13] It was previously on display at the Dornier-Fairchild factory in Oberpfaffenhofen.[14] This aircraft has the fuselage of Aviolanda-built WNr. 5291, mated with the original wing of the Do 24 that became the Do 24 ATT:[15] Werknummer 5345.[16]
• Unknown – Do 24 T fuselage on display at the Technik Museum Speyer in Speyer, Rhineland-Palatinate.[17]
• 5345 – Do 24 ATT airworthy with Iren Dornier of Uhldingen-Mühlhofen, Baden-Württemberg.[18][19] It has been re-engined with three PT6A-45B turboprops.[20] In February 2004, it began flying around the world on a UNICEF mission to assist children in the Philippines.[21] The Do-24 ATT is piloted by Iren Dornier, the grandson of Dornier founder Claudius Dornier.[22] Upon completion of the work with UNICEF, it will be run as a special charter airliner by South East Asian Airlines. It was flying at the Berlin ILA in May 2014, equipped with the Advanced Technology Wing developed during the Dornier 228 program. It was then the only airworthy Do 24 of any sub-type.[23] It was built from Werknummer 5345.[24]

Netherlands

• 3387 – Do 24 T-3 on static display at the Nationaal Militair Museum in Soesterberg, Utrecht. It is painted in the livery of the Marine Luchtvaartdienst.[25][26]

Spain

• 2134 – Do 24 T-3 on static display at the Museo del Aire in Cuatro Vientos, Madrid.[27][28]

Data from Aircraft of the Third Reich Volume one,[29] German Aircraft of the Second World War,[30] The Cosmopolitan Dornier...Last of the Sponson 'Boats[31]

General characteristics

• Crew: 4 or 6[32]
• Length: 22.05 m (72 ft 4 in)
• Wingspan: 27 m (88 ft 7 in)
• Height: 5.75 m (18 ft 10 in)
• Wing area: 108 m² (1,160 sq ft)
• Empty weight: 9,400 kg (20,723 lb)
• Gross weight: 13,700 kg (30,203 lb)
• Max takeoff weight: 18,400 kg (40,565 lb)
• Fuel capacity: 5,300 l (1,400 US gal; 1,200 imp gal) in two 1,000 l (260 US gal; 220 imp gal) wing tanks and twelve small tanks in the sponsons
• Powerplant: 3 × Bramo 323R-2 Fafnir 9-cylinder air-cooled radial piston engine, 704 kW (944 hp) each
• Propellers: 3-bladed VDM variable-pitch metal propellers

Performance

• Maximum speed: 330 km/h (210 mph, 180 kn) at 2,600 m (8,500 ft)
  

290 km/h (180 mph; 160 kn) at sea level

• Cruise speed: 295 km/h (183 mph, 159 kn) at 2,600 m (8,500 ft) (maximum continuous)
• Range: 2,900 km (1,800 mi, 1,600 nmi)
• Ferry range: 4,700 km (2,900 mi, 2,500 nmi)
• Service ceiling: 7,500 m (24,600 ft)
• Time to altitude: 2,000 m (6,600 ft) in 6 minutes
  

4,000 m (13,000 ft) in 13 minutes 12 seconds

Armament

• Guns:
  
  • 1 x 20 mm (0.787 in) Hispano HS.404 or 20 mm (0.787 in) MG151 cannon in dorsal turret
  • 1 × 7.92 mm (0.312 in) MG 15 machine gun in nose turret
  • 1 × 7.92 mm (0.312 in) MG 15 machine gun in tail gun position
• Bombs: 1.200 kg (2,645 lb) of bombs under the wings

Aircraft of comparable role, configuration, and era

• Blackburn Sydney
• Latécoère 300
• PBY Catalina
• Kawanishi H6K
• Potez-CAMS 141
• Aichi H9A

Related lists

• List of aircraft of World War II
• List of Interwar military aircraft
• List of military aircraft of Germany
• List of seaplanes and amphibious aircraft
• List of World War II military aircraft of Germany

• "Back to Base". Air Enthusiast. Vol. 2 no. 1. January 1972.
• Donald, David (1994). Warplanes of the Luftwaffe. London: Aerospace Publishing. ISBN 978-1-874023-56-2.
• Green, William; Swanborough, Gordon (April–July 1983). "The Cosmopolitan Dornier...Last of the sponson 'boats". Air Enthusiast. No. Twenty–one. pp. 9–20. ISSN 0143-5450.
• King, H.F. (9 November 1939). "The Dornier Flying Boats". Flight. Vol. XXXVI no. 1611. pp. a–d (between p. 372 and p. 373).
• de Jong, Peter (2015). Dornier Do 24 Units (Osprey Combat Aircraft No. 110). Oxford: Osprey Aerospace. ISBN 978-1-4728-0570-6.
• Smith, J. R.; Kay, Antony L. (1972). German Aircraft of the Second World War. London: Putnam. ISBN 0-85177-836-4.
• Sullivan, Les (1984). "Talkback". Air Enthusiast. No. 25. p. 79. ISSN 0143-5450.

• Web page dedicated to the latest flight of the last airworthy Do.24 in the world

Wikimedia Commons has media related to Dornier Do 24.

• Do.24ATT World Tour - An Iren Dornier Project
• Dornier Do.24 & Do.24 ATT Detailed specs at flugzeuginfo.net
• Site dedicated to the Do.24
• photos and documents about Do.24 in Rio de Janeiro, Brazil, March, 2006
• Article in 'Kölner Stadt Anzeiger' showing three photos of the Do.24 in flight on 20 May 2006 (German)
• UNICEF article describing the mission of the Do.24 ATT
• Dornier Do.24 by Hydravore.com (French)
• Do.24 in Oberschleißheim
• Complete list of surviving Do.24 (and other Dornier) aircraft and fragments
• Video: short stop