Prototypes

According to the demands of the RLM the Do-24 V1 and Do-24 V2 were equipped with three Junkers Jumo 205C diesel engines generating 600 hp. The Do-24 V3 and Do-24 V4 were the third and fourth prototype, but were the first two prototypes to fly. Both were part of the first Dutch order for six aircraft and were equipped with three Wright Cyclone GR-1820-F52 radial engines. The choice for these engines was made because the Fokker T.IV and the large order for the Glenn Martin 139 bomber for the Dutch East Indies were equipped with this engine. The engine was 15% lighter and gave 50% more power than the Junkers diesels.
The first flight of any Do-24 took place on July 3rd 1937 when the Do-24 V3 took to the air from the Bodensee with Dornier factory pilot Erich Gundermann at the controls. One day later the aircraft was handed over to the MLD (Marine Luchtvaart Dienst, Dutch Naval Aviation) and September 5th the aircraft, now with the registration D-ADLP, was flown to the Weser Flugzeugwerke at Einswarden for the sea trials which were to be held on the North Sea, supporting ship for these trials was the Greif. The seaworthiness of the Do-24 V3 amazed the spectators, there were times when the cockpit of the aircraft was completely submerged. The trials lasted till the end of October and were concluded to full satisfaction. November 10th 1937 the Do-24 V3, now known as Do-24K-1 with the registration X-1, was shipped from Hamburg to Morokrembangan in the Dutch East Indies. Early 1938 the aircraft was ready for it's first mission.
The Do-24 V1 made it's first flight on January 10th 1938, shortly thereafter followed by the Do-24 V2 (D-AIBE). A series of tests at the Erprobungsstelle (E-Stelle) Travemünde made clear that the Jumo engines were not adequate for the job. This caused the RLM to stop any orders for the Do-24 and go with the Blohm und Voss Bv-138 (the earlier Hamburg Ha-138). Both prototypes were stored at the E-Stelle Travemünde.
When on April 9th 1940 the Germans invaded Denmark and Norway the Luftwaffe had some stiff opposition at Narvik in the northwest of Norway and was in need of seaworthy flying boats capable of bringing supplies to the German troops at Narvik, because there was no other way in to the city. April 12th A. Mlodoch, pilot of the E-Stelle Travemünde, was ordered to take the Do-24 V1 TJ+HR and three Bv-138's to Narvik as part of KGzbV 108-See (Kampfgeschwader zum besondere Verwendung 108-See). Hastily both open gun positions of the Do-24 V1 were fitted with a removable MG 15 machine gun, the B-Stand (middle position) was already fitted with a Rheinmetall-Borsig MG 204. The three Bv-138's proved unable to take off due to the weather so the Do-24 V1 was the only one to go to Narvik despite the bad weather reports. On the way to Narvik the plane was shot upon by English ships but remained unharmed. At 21:18 hours a landing was made due to the coming darkness in a fjord, also to be able to make out the position of the aircraft. In the haste no maps were taken along and the only map available was a school atlas. The next day at 13:24 hours the Do-24 V1 reached Narvik and came under fire from English torpedo boats. The plane was anchored on a buoy between the many shipwrecks in the harbor and was thus covered from enemy fire. With a speedboat the crew was brought to land and heard that the harbor could be evacuated at any moment. Mlodoch and his crew fled to an empty house and watched the battle and his Dornier. As the battle raged they decided to look for a machine gun nest so if they had to they could shoot their own plane to prevent it from falling into enemy hands. He didn't have to wait long as the English tried to tow the Do-24 V1 out of the harbor with a small boat. One well aimed salvo persuaded the English to break the lines and leave the aircraft where it was. Thus the Do-24 V1 was floating around in the harbor and was oddly enough relatively unharmed as the battle went on. Despite the damage the crew wanted to return to Travemünde as soon as possible. During the night of April 16th, under heavy enemy fire, at 03:28 hours the Do-24 V1 took off. Besides the crew there were three passengers, two wounded German naval officers and a English POW, who later turned out to be the nephew of Winston Churchill. The first goal was to get diesel for the engines, they were in luck and when passing Denmark they spotted a German tanker unit and were able to take on enough fuel for the remaining trip. At 15:49 hours the Do-24 V1 landed safely on the waters of the Potenitzer Wiek near Travemünde. April 19th a second transport flight was ordered to Narvik with as main cargo 2000 kg of dynamite.This time the Do-24 V2 was to be used with the military registration DP+DH, because the Do-24 V1 was still in repair. After a 27 minute test flight with the Do-24 V2 Mlodoch decided to take the Do-24 V1. That same night the Do-24 V1 was ready and the next day the flight was made without any problems. After this both prototypes were active in the battle for Norway.
September 1940 the Do-24 V1 made an emergency landing near the Norwegian city Vardo in the Barentssea and was just able to roll onto the beach there. After removing the engines and the wingtips the plane was pulled out by a fishing ship and brought to the harbor of Vardo. After this nothing was ever heard of the Do-24 V1. The Do-24 V2 returned to Travemünde after the occupation of Norway and had to be scrapped due to the damages.

Do-24 V1

Do-24 V2

Do-24 V3

Do-24 V4