Dornier Do 18

Civil service

In 1936, Deutsche Luft Hansa started a series of endurance trials, culminating on 10–11 September when Zephir, flown by Flugkapitän Blankenburg with Deutsche Luft Hansa Director Freiherr von Gablenz as passenger, was launched by catapult from the seaplane tender Schwabenland at Horta, Azores, flying the 4,460 km (2,270 mi) to New York City in 22 hours 12 minutes.^[5] Also on 11 September, Aeolus flew from Horta to Hamilton, Bermuda in 18 hours 15 minutes,^[5] continuing to New York the next day. For the main leg of the North Atlantic the aircraft needed the help of the catapult on Schwabenland. On 22 September Aeolus returned to Horta in 17:50 h (3850 km). Zephir was catapulted on 28 September at Hamilton. Further flights to New York followed on 5–6 and 6–7 October and the return flights this time, 17 and 18 October from Sydney, Nova Scotia. The flying boats did not wait for their tender and went on to Lisbon and Travemünde.

In April 1937, D-ARUN Zephir and D-ABYM Aeolus started service on the South Atlantic mail route from Bathurst, now Banjul, Gambia to Natal, Brazil (3040 km). Catapult ships were based in Bathurst and Fernando de Noronha to allow the aircraft to cross the Atlantic carrying a full load of mail.

In June they were joined by V6 D-AROZ Pampero. Aeolus was lost on 30 July 1937, when it had to make an ocean landing due to engine problems and was heavily damaged when Ostmark tried to retrieve the plane. Pampero (20 August) and Zephir (29 January 1938) also had to make ocean landings. Pampero was lost at sea nearly without trace on 1 October 1938 with a crew of five.

Deutsche Luft Hansa's fifth aircraft was the only Do 18F V7 D-ANNE Zyklon, that first took to the skies on 11 June 1937. This was the only Do 18 with a wider span, which enabled it to stay in the air with one engine out. This was a special demand of Deutsche Luft Hansa. Zyklon was used over the South Atlantic between September 1937 and March 1939. The Do 18s crossed the South Atlantic 73 times.

Zyklon is not the aircraft that established the England to Brazil distance record from 27–29 March 1938 as often stated.
^{[citation needed]} The record-setting aircraft D-ANHR was taken from the military production line and was specially prepared. It was flown as a builder's machine with a Deutsche Luft Hansa crew augmented by the works pilot Gundermann. On the way back to the South American station the seaplane tender Westfalen took the aircraft into the English Channel where it was catapulted to Brazil. On the record flight the conditions were not optimal and the Do 18 did not reach Rio de Janeiro as planned.

Military use

In Luftwaffe service, it was obsolete by the outbreak of World War II, but, as the only military flying boat, 62 (58 serviceable) Do 18s equipped a Staffel in each of five Kürstenfliegergruppen (Coastal aviation groups)^[8] mainly on North Sea reconnaissance missions. In 1940 some squadrons changed their base to Norway. The vulnerable and underpowered flying boat was soon relegated to training and the air/sea rescue role. In the middle of 1941, only one squadron was still operational on Do 18. The Blohm & Voss BV 138 had superseded the Dornier.

A Do 18 was the first German aircraft to be shot down by British aircraft during the war, when one of a formation of three was caught over the North Sea by nine Fleet Air Arm Blackburn Skua fighter-bombers of 803 Naval Air Squadron flying from HMS Ark Royal on 26 September 1939. The flying boat was able to make an emergency landing but was sunk by the destroyer HMS Somali.^[9][10]

Civil variants

Do 18E

Initial civil version, powered by 410 kW (550 hp) Jumo 205C-1 engines.^[5] Four built.^[6]

Do 18F

Long range civil version V7 D-ANNE Zyklon, with extended-span (26.30 m (86 ft 3 in)) wings and increased take-off weight. One built.^[6]

Do 18L

The record-aircraft D-ANHR modified with BMW 132M radials. One converted.^[7]

Military variants

• The Do 18D 79 built, was the first military version, powered by two 450 kW (600 hp) Jumo 205C engines, armed with one 7.92 mm (0.312 in) MG 15 machine gun in the bow and dorsal positions.
• The Do 18G 62 built, was an improved version, powered by two 656 kW (880 hp) Jumo 205D engines, armed with a 13 mm (0.51 in) MG 131 machine gun in the bow, and a 20 mm MG 151 cannon in a power-operated dorsal turret. This version had an altered bow contour and broader sponsons. Provision for rocket-assisted take off (JATO) was possible.^[8]
• The Do 18H 22 built (+ conversions ?) was an unarmed dual-control six seat training version.
• The Do 18N was a designation for unarmed air-sea search and rescue conversions in service with the Seenotdienst^[8]

Including the civilian flying boats 170 Dornier Do 18 were built by Dornier in Manzell (48 until March 1939) and Weser Flugzeugbau in Einswarden and Nordenham (122 until August 1940).