Dornier Do 17Z
The Dornier Do 17Z was the main production version of the Luftwaffe's slim-fuselaged "Flying Pencil" bomber, redesigned with a deep glazed nose and heavier defensive armament after combat experience in Spain. It fought through the early campaigns of the Second World War and the Battle of Britain, where it proved the most vulnerable of the German medium bombers, and was leaving front-line service by 1941. One aircraft survives: a Z-2 raised from the Goodwin Sands in 2013 and conserved by the RAF Museum.
Why It Mattered
The Dornier Do 17Z was the main production form of Germany's "Flying Pencil" bomber, the variant that carried the type into the Battle of Britain. It was a 1930s fast-bomber design overtaken by events: quick enough to escape the fighters ranged against it in Spain, it met radar-directed Hurricanes and Spitfires over England that could overhaul it with ease. Its deep, glazed nose and added gun positions were Dornier's answer to combat experience, an attempt to make a lightly built bomber defensible without thickening the slim fuselage that gave it speed. By 1941 it was leaving front-line service, but in 1940 it had been one of the Luftwaffe's standard medium bombers over Britain, and the most vulnerable of them.
Design Notes
The Z kept the Do 17's slim, shoulder-winged airframe but rebuilt the front end: the cockpit area was dropped and extended further, the nose fully glazed, and a prone gunner placed in a bulged section underneath to fire an MG 15 aft. The design had been drawn around Daimler-Benz inline engines, but those were reserved for fighters, so the Z flew with Bramo 323 radial engines instead. The first production model, the Z-1, was underpowered on its Bramo 323A-1s and could carry only a 500 kg bomb load; the Z-2 restored the load to 1,000 kg on 1,000 hp Bramo 323P engines. Defensive armament grew to as many as eight MG 15 machine guns, though the beam guns' field of fire was severely limited by their position next to the engines. Variants multiplied within the same airframe: the Z-3 reconnaissance model, the Z-4 dual-control trainer, the Z-5 maritime version with flotation bags, and the Kauz night fighters with a solid gun nose in place of the glazing.
Operational History
Z production ran through 1939 and 1940, and the type fought from the war's first campaigns, over Poland, Denmark, Norway, the Low Countries and France. In the Battle of Britain the Do 17 Gruppen, among them KG 2, KG 3 and III./KG 76, came up against determined fighter opposition and suffered more heavily than the He 111 or Ju 88. Some pilots escaped attack by going into a high-speed dive, but that prevented them from carrying out their bombing mission. The Do 17 units played their part in the night-time Blitz of 1940–41, yet production had ended in 1940, and by January 1941 only KG 2, III./KG 3 and KGr. 606 were still using the type. Four bomber groups used the Do 17 during the invasions of Greece and Yugoslavia, and KG 2 used it on the eastern front in June 1941 before being withdrawn the following month to re-equip with the Do 217. Small numbers remained in use with reconnaissance units until early in 1943, and the Kauz night fighters — a single Z-6 and nine Z-10s — had a short combat life before being replaced by the Ju 88C. Finland received fifteen Do 17Zs in January 1942, and the Finnish Air Force kept the type in service until 15 September 1952.
Afterlife
No Do 17 was known to survive intact until divers spotted one in 2008: a Do 17Z-2, Werknummer 1160, lying in 50 feet of water on the Goodwin Sands off the Kent coast. The aircraft, coded 5K+AR of 7./KG 3, had been shot down on 26 August 1940 by Boulton Paul Defiants of No. 264 Squadron after it became separated from the rest of its formation and lost its bearings; its pilot force-landed on the sands at low tide. The RAF Museum raised the wreck on 10 June 2013 and conserved it at Cosford in purpose-built hydration tunnels, spraying the airframe with a low-concentration citric acid solution developed alongside scientists at Imperial College London. The museum calls it the only known substantially intact Dornier Do 17, and the sole surviving example of the type. A wing is now on display in the War in the Air Hangar, next to the Boulton Paul Defiant — the type that brought the Dornier down — with its engines and propeller alongside, while the fuselage remains in storage at the Conservation Centre for now.