Dornier Do 24

Summary

Do 24
Dornier Do24K in flight c1938.jpg
A Dutch Do 24 flying-boat
Role Bomber, reconnaissance and air-sea rescue flying boat
National origin Nazi Germany
Manufacturer Dornier Flugzeugwerke
Built by Aviolanda
SNCAN
First flight 3 July 1937
Introduction November 1937
Retired 1967 (Spanish Air Force)
Primary user Luftwaffe
Produced 1937–1945
Number built 279

The Dornier Do 24 is a 1930s German three-engine flying boat designed by the Dornier Flugzeugwerke for maritime patrol and search and rescue. A total of 279 were built among several factories from 1937 to 1945.

Design and development

Dornier Do 24 V3 prototype in Dutch markings

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]

Diesel-powered Luftwaffe Do 24 V1 trials aircraft being used as an air-sea rescue aircraft

Do 24 V3, the first of the Dutch X boats, as they would be called in Dutch service, 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 450 kW (600 hp) 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 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 additional fuel.[5]

With the German occupation, production was paused, however while the Luftwaffe Küstenfliegergruppen Maritime reconnaissance branch was uninterested in the partially completed aircraft as they had already chosen the Blohm und Voss Bv 138 for the role, the Dutch production line resumed, to provide aircraft for the otherwise poorly equipped Seenotdienst (Sea Emergency Service), which was still operating Heinkel He 59 biplanes.[6] The 13 airframes on the Aviolanda assembly line were completed with Dutch-bought Wright Cyclone engines but later models used the BMW Bramo 323R-2. An additional 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 CAMS factory at Sartrouville, France, during the German occupation. This line was operated by SNCAN and produced 48 Do 24s during the war and another 40 after the liberation of France, which served with the French Navy until 1952.

Operational history

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.[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.

Variants

Restored Do 24 ATT re-engined with Pratt & Whitney PT6A-45 turboprop engines
Do 24 V1
Luftwaffe trials aircraft powered by three 450 kW (600 hp) Junkers Jumo 205C liquid-cooled diesel inline engines.[8]
Do 24 V2
Luftwaffe trials aircraft similar to V1
Do 24 V3
Dutch trials aircraft with three 660 kW (880 hp) Wright R-1820-F52 Cyclone air-cooled radial engines. Later became the first Do 24K-1, and was the first Do 24 to fly. Assigned serial X-1.[9]
Do 24 V4
Second K-1 for Dutch trials, Assigned serial X-2.[9]
Do 24K-1
Swiss production by Dornier & Dutch license production aircraft, 36 built. The German civil registration D-AYWI was allocated for these for their ferry flights to Holland from Dornier's production facility in Switzerland.[10]
Do 24K-2
Dutch licence production powered by three 750 kW (1,000 hp) Wright R-1820-G102 Cyclone engines. 1 example completed by Dornier while 13 incomplete airframes were captured by the Germans, and modified for air-sea rescue with additional hatches and a hoist as 24N-1s.[6]
Do 24N-1
13 incomplete Dutch Do 24K-2s being built in Holland completed for the Luftwaffe for air-sea rescue, powered by three 750 kW (1,000 hp) Wright R-1820-G102 engines. As supplies of spares for the R-1820s ran out, surviving aircraft were re-engined with 645 kW (865 hp) BMW 132N radials.[11]
Do 24T-1
French production, 48 built
Do 24T-1
Dutch production for the Luftwaffe powered by three 750 kW (1,000 hp) BMW Bramo 323R-2 Fafnir radial engines, 159 built (including T-2 and T-3).
Do 24T-2
as Do 24T-1 with minor changes to equipment and weapons.
Do 24T-3
as Do 24T-1 with minor changes to equipment and weapons.
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.

Operators

 Australia
 France
 Nazi Germany
 Netherlands
 Norway
 Soviet Union
 Spain
 Sweden

Surviving aircraft

Dornier Do 24 on display
Australia
France
Germany
  • 5345[21] – Do 24 ATT , an extensively modified ex-Spanish Do 24 T-3 fitted with a Dornier 228 type Advanced Technology Wing,[22] re-engined with three PT6A-45B turboprops,[23] and fitted with retractable undercarriage, converting it from a pure flying boat, into an amphibian.[24] In February 2004, it began an around the world flight on behalf of UNICEF to raise money for children in the Philippines,[25] piloted by Iren Dornier, Claudius Dornier's grandson.[26]
Netherlands
Spain

Specifications (Do 24T-1)

Dornier Do 24 drawings.png

Data from Aircraft of the Third Reich Volume one,[31] German Aircraft of the Second World War,[32] The Cosmopolitan Dornier...Last of the Sponson 'Boats[33]

General characteristics

  • Crew: 4 or 6[34]
  • 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:
  • Bombs: 1,200 kg (2,600 lb), under the wings

See also

Aircraft of comparable role, configuration, and era

Related lists

References

Notes

  1. ^ Green and Swanborough Air Enthusiast April–July 1983, pp. 9–10.
  2. ^ a b c d Green and Swanborough Air Enthusiast April–July 1983, pp. 10–11.
  3. ^ Smith and Kay 1972, p. 121.
  4. ^ King Flight 9 November 1939, p. b.
  5. ^ a b Green and Swanborough Air Enthusiast April–July 1983, p. 11.
  6. ^ a b de Jong, 2015, p.13
  7. ^ Visser, Jan (1999–2000). "Who sank IJN destroyer Shinonome, December 1941?". Forgotten Campaign: The Dutch East Indies Campaign 1941–1942.
  8. ^ de Jong, 2015, p.10 & 11
  9. ^ a b de Jong, 2015, p.11
  10. ^ Pentland, Andrew (13 June 2014). "Civil Aircraft Register - Germany". Golden Years of Aviation. Retrieved 23 December 2021.{{cite web}}: CS1 maint: url-status (link)
  11. ^ de Jong, 2015, p.15
  12. ^ Broshot, James A. "Dutch Air Force Order of Battle in the Dutch East Indies, 30 November 1941". Forgotten Campaign: The Dutch East Indies Campaign 1941–1942.
  13. ^ de Jong 2015, pp. 84–85.
  14. ^ "RAAF A49 Dornier Do24K". ADF-SERIALS. Retrieved 12 December 2016.
  15. ^ de Zwart, Andre. "Do-24K-1 at Echuca, Australia". Dornier Do-24. Retrieved 12 December 2016.
  16. ^ de Zwart, Andre. "Do-24T-3 at Bad Zwischenahn". Dornier Do-24. Retrieved 12 December 2016.
  17. ^ "Dornier Do 24 T-3". Deutsches Museum Flugwerft Schleissheim. Retrieved 12 December 2016.
  18. ^ de Zwart, Andre. "Do-24T-3 at the Dornier-Fairchild factory in Oberpfaffenhofen, Germany". Dornier Do-24. Retrieved 12 December 2016.
  19. ^ "AirVenture News: Dornier Do 24 in der Museumswerkstätte der Flugwerft Schleißheim". AirVenture News. Retrieved 22 September 2018.
  20. ^ de Zwart, Andre. "Do-24T at Speyer, Germany". Dornier Do-24. Retrieved 12 December 2016.
  21. ^ "Dornier Do 24 - Eine Ode an das Erbe". Süddeutsche Zeitung. Retrieved 22 September 2018.
  22. ^ Air Britain Aviation World pp. 127, 129, September 2014
  23. ^ Doerk, Christian. "Amphibian Do 24ATT". Amphibian Do 24ATT World Tour. do-24.com. Retrieved 12 December 2016.
  24. ^ de Zwart, Andre. "Do-24ATT". Dornier Do-24. Retrieved 12 December 2016.
  25. ^ Doerk, Christian. "Mission: DREAM". Amphibian Do 24ATT World Tour. do-24.com. Retrieved 12 December 2016.
  26. ^ Doerk, Christian. "IREN DORNIER - Founding Chairman". Amphibian Do 24ATT World Tour. do-24.com. Retrieved 12 December 2016.
  27. ^ "Dornier Do-24K .1 "X-24"". NMM (in Dutch). Nationaal Militair Museum. Retrieved 12 December 2016.
  28. ^ de Zwart, Andre. "Do-24T-3 at Soesterberg, The Netherlands". Dornier Do-24. Retrieved 12 December 2016.
  29. ^ "Hangar 6 del Museo de Aeronáutica y Astronáutica" (in Spanish). Ejército del Aire. Archived from the original on 20 December 2016. Retrieved 12 December 2016.
  30. ^ de Zwart, Andre. "Do-24T-3 at the Museo del Aire in Madrid, Spain". Dornier Do-24. Retrieved 12 December 2016.
  31. ^ Green, William (2010). Aircraft of the Third Reich Volume one. London: Crecy. pp. 242–251. ISBN 9781900732062.
  32. ^ Smith, J.R.; Kay, Antony L. (1972). German Aircraft of the Second World War. London: Putnam. pp. 121–123. ISBN 978-0-85177-836-5.
  33. ^ Green and Swanborough Air Enthusiast April–July 1983, p. 15.
  34. ^ Donald 1994, p. 36.

Bibliography

  • "Back to Base". Air Enthusiast. Vol. 2, no. 1. January 1972.
  • de Jong, Peter (2015). Dornier Do 24 Units (Osprey Combat Aircraft No. 110). Oxford: Osprey Aerospace. ISBN 978-1472805706.
  • Donald, David (1994). Warplanes of the Luftwaffe. London: Aerospace Publishing. ISBN 978-1874023562.
  • 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).
  • Smith, J. R.; Kay, Antony L. (1972). German Aircraft of the Second World War. London: Putnam. ISBN 978-0851778365.
  • Sullivan, Les (1984). "Talkback". Air Enthusiast. No. 25. p. 79. ISSN 0143-5450.

External links

  • Do 24ATT World Tour - An Iren Dornier Project