Designed as a high-speed mail plane for Deutsche Lufthansa and first flown in 1934, the Do-17 soon "changed specialization". Three single-fin aircraft of this model were followed by 12 prototypes of a new high-speed bomber with a two-fin tail. This aircraft entered service from the beginning of 1937 and soon earned the nickname "flying pencil" for its strongly elongated fuselage.

The first combat modification had two designations: Do-17E-1 - high-speed bomber and Do-17F-1 - long-range photographic reconnaissance; on the latter, instead of a bomb load, additional fuel tanks and two cameras were installed. These two models were distinguished by high speed and were considered to be fully and completely in line with the standards of that time, but quickly became obsolete.

Drawing Dornier Do17 E-1

Dornier Do 17E-3 in USSR before WWII. At least twice, aircraft in good working order fell into the hands of Soviet specialists. On 20 March 1941, a Do 17E-1 landed at Bel'sk Airfield in western Byelorussia and, the next day, a Do 17E-3 landed in the town of Tsekhanovets. In both cases, the crews allegedly had lost orientation in adverse weather conditions. The aircraft belonged to the Warsaw and Torn Aviation schools, respectively, and were examined in detail by Air Forces Scientific Research Institute engineers who had urgently proceeded there.

These airplanes compared unfavorably with the Do 215 the USSR previously had purchased. Russian specialists noted the small cockpit with poor visibility, insufficient fire angles, and low-powered BMW VI engines. An inspection report signed by Military Engineers 1st Rank Kulikov and Avakimyan and Military Engineer 2d Rank Gul'nick reflected the following: "The Do 17s built in 1936-1937 are obsolete, the Germans are withdrawing them from service with combat aviation and transferring them to flying schools for use as trainers...These aircraft are of no interest to us".

The captured airplanes were returned to Germany and it is known that the Germans used at least one of them, the aforementioned Do 17E-3 No. 3003, for glider towing during the war with the Soviet Union until 1943.

Do-17 E-1 Condor Legion, Spain 1938.

Photo	Description
	Drawing Do17M
	Dornier Do 17E-3 No.3003 reconnaissance aircraft that made an emergency landing on USSR soil in March 1941. After being examined, the aircraft was returned to Germany.

Do-17 Modifications

• Do 17E-1 - the first serial modification of the bomber, produced since 1937. The bomb load was only 500 kg; defensive armament consisted of one 7.92-mm machine gun mounted openly in the rear of the cockpit. The aircraft was tested in combat in Spain.
• Do 17F-1 - a three-seat reconnaissance aircraft produced in parallel with the "E" modification. Aerial cameras RB 50/18 or RB 50/30 were installed in the bomb bay and LC 50F lighting bombs were suspended.


Reconnaissance aircraft Do-17F-1 # 27-17; Condor Legion, Spain 1938. In the foreground is the SB-2M-100 captured by the Francoists.

Drawing Dornier Do 17 F-1

• Do 17K is an export version of the Do 17 designed for Yugoslavia. It had French engines Gnome-Rum 14N1/2. There were variants of the Do 17Ka-1 bomber and Do 17Ka-2 and Do 17Ka-3 reconnaissance aircraft.

• Do 17M is a further development of the "E" modification with an electric retractable landing gear, a closed upper rear firing point and two Bramo 322A-1 engines. Bomb load increased to 1000 kg.

• Do 17Р - reconnaissance aircraft, similar in design to the "M" modification. Aircraft Do 17, modifications "M" and "P" were built under license in Yugoslavia. The total number of vehicles built was approximately 70 units.


Drawing Dornier Do 17 P-1

• Do 17R is an experimental aircraft for testing engines and special equipment.
• Do I7S is an experimental high-speed reconnaissance aircraft with DB 600G engines and a new cockpit with a large glass area.
• Do 17U - modification of the air command post with a crew of five, developed on the basis of modification "Z".
• Do 17Z - developed on the basis of the experience of the war in Spain and produced since 1939, the main serial modification. A total of 509 vehicles of this modification were produced, there were the following options:

• Do 17Z-0 - prototype aircraft of modification "Z". which was a development of the "S" modification with two Bramo 323A-1 engines with a capacity of 900 hp. With. and with defensive armament from three 7.92-mm MG 15 machine guns.
• Do 17Z-1 is a serial version with an additional 7.92 mm bullet in the forward fuselage. The bomb load was clearly insufficient - 500 kg.
• Do 17Z-2 - variant with 1000-hp Bramo 323Р engines, bomb load increased to 1000 kg.
• Do 17Z-3 - photo reconnaissance variant, 22 aircraft produced.
• Do 17Z-4 is a dual-control trainer aircraft.
• Do 17Z-5 is an experimental aircraft used to develop rescue equipment for bombers shot down over the sea. Had inflatable rubber bags in the bomb bay and in the engine nacelles.
• The Do 17Z-6 and Z-10 are night-time attack fighters developed in 1940 to combat British bombers. They had powerful machine-gun and cannon armament and infrared aircraft detection equipment.

Bibliography

• "Aviation of Luftwaffe" /Viktor Shunkov/
• "The German Imprint on the History of Russian Aviation " /D.A. Sobolev, D.B. Khazanov/
• "Encyclopedia of military engineering" /Aerospace Publising/