Dornier Do 17 (Flying Pencil)

History of Dornier Do 17 (Flying Pencil)

The Dornier Do 17 was a medium-range bomber primarily used by the Luftwaffe in the years leading up to World War II. The aircraft was widely used in the early days of the war and played a major role in the fall of the Netherlands, Belgium and France. It was also used in invasions of the Balkans, Greece and Crete, and saw its last major involvement in the invasion of the Soviet Union. While Germany never kept revolutionary stable bombers in its inventory, aircraft like the Do 17 formed a large part of the first German pioneers in Europe.

The plane was nicknamed the "Flying Pen" because of its thin shape, resembling a writing instrument. In total, approximately 2,139 Dornier Do 17 bombers and related derivatives were completed.

Background

After World War I, Germanys ability to wage war was severely limited under the terms of the 1919 Treaty of Versailles, which placed primary responsibility for the war on the German Empire. Therefore, the country does not allow any military aircraft, submarines (or warships of any kind) or tanks. Their internal defense is handled by a small standing army and armored vehicles performing policing duties.

That all changed when Adolf Hitler came to power and got the chancellery, eventually becoming a dictator. To curb unemployment, protect middle-class believers, and build his war machine, he put Germans to work in factories that made his weapons of war.

In the years leading up to the total war in Europe, the German propaganda machine controlled the minds of the German people. It took advantage of the greatness of German discovery and creation and set out to create a bloated new German image. This is the case with aircraft development, where designs emerge that promote specific advantages in their respective civilian appearances. It didn't take long for the military value of these designs to be recognized by German authorities and external parties such as Britain and France.

Having said that, many of the early Luftwaffe aircraft were rebuilt as little more than modifications of these commercially oriented aircraft. While these systems performed well in their original form, when converted to their military cousins, the life limitations of these systems quickly became apparent - and the Dornier Do 17 was no exception.

Dornier Do 17 Origins

The Dornier Do 17 series of aircraft started in 1932 as a dedicated commercial enterprise. Dornier built a mail plane with limited passenger seating that used a slender fuselage, two engines on a high-mounted monoplane and a vertical tail. The cockpit is located at the very forward end of the aircraft, and the passenger cabin is actually made up of two separate areas - a two-seat unit mounted aft of the cockpit and a four-seat unit mounted aft of the main spar. Internal reservations for shipping manage goods. The first Do 17 V1 prototype entered service in 1934.

Dornier then delivered two similar prototypes to Lufthansa for evaluation, but both were rejected, especially because of their separate cabin layouts. The Do 17 struggled before Dornier test pilots considered designing the airframe for a military bomber company in the Luftwaffe. Dornier engineers then redesigned the type, removing the passenger and cargo compartments and adding an internal bomb bay, and splitting the single vertical tail into two smaller vertical tails (the latter moved for the back gunners) Provides an unrestricted vantage point to warrant). Defensive weapons have been added to complete the transformation.

Dornier then produced five more prototypes that fit this design, and the militarized Do 17 was born.

Dornier Do 17 is born

At launch, the Do 17 was a great performer. It turned out to be developing faster than any fighter jet of the time, and it handled essentially fighter jet-like. Pilots appreciate their solid status, and their flight characteristics are exemplary for this class of aircraft.

The Luftwaffe entered service with this model and started production from two similar models - the Do 17E-1 and the Do 17F-1. The Do 17E-1 is a dedicated medium bomber with an internal bomb load of 1,100 pounds, while the Do 17F-1 is a dedicated reconnaissance platform that reduces bomb load in favor of the addition of two down-facing reconnaissance cameras (Rb 50/30 and Rb 75/ 30) and extra internal fuel for increased operating range.

Both brackets feature a liquid-cooled 750-horsepower BMW VI inline engine in limited production.

Dornier played 17 rounds

In its finished production form, the Do 17 still retains most of its original mail/passenger source. All flight positions remain at the front of the fuselage. Therefore, many glasses were added to improve the respective vantage points. The wings were mounted on the shoulders along the thin hull and forward of the midship. The wings are designed to be straight with tapered ends.

The leading edge of each wing features radial piston engines in a streamlined nacelle. The fuselage tapers to the tail, with a twin vertical tail configuration attached. This provides the rear gunner with a wider range of firepower.

The landing gear is of a traditional arrangement with a pair of main gear legs and a tail wheel - all fully retractable into the engine nacelle (main outriggers) and tail.

Armed

The glass nose houses a crew member who can use a forward-facing machine gun. The lower flight deck floor is a pod-like appendage with a rear-facing, downward-pointing machine gun designed to counter enemy attacks from below and behind.

A rear gunner is located at the rear of the flight deck and can cover the most important rear and upper quadrants of the Do 17 with machine guns. Side gunners manage machine guns designed to deter side attacks from oncoming enemy fighters. Overall, the Do 17's base crew had access to four machine guns in early models and up to eight machine guns in later models. The machine gun is the MG 15 series of 7.92mm caliber. Over the life of the aircraft, bomb loads range from 1,000 pounds to over 2,000 pounds (depending on variant).

Needless to say, the combat conditions on each Do 17 airframe were relatively cramped.

First Battle - Spanish Civil War

Before long, many early German military creations were officially baptized by fire. Spain was embroiled in a civil war known simply as the Spanish Civil War (1939-1939), in which the army of the republican government confronted rebellious nationalists. Germany sided with the Kuomintang, throwing in new Do 17 bombers, Junkers Ju 87 dive bombers, Messerschmitt Bf 109 fighter jets and Panzer light tanks. Both series versions of Do 17 eventually made it to the forefront as part of "Legion Condor".

In battle, these types are special, surpassing the qualities of the warriors who try to destroy them. Their bombing nature made them deadly adversaries, and the design was considered a pass.

Post-action revisions

Work has begun on improved forms of the two Do 17 production models. These became the names Do 17M and Do 17P respectively. Both versions are designed to fit Daimler-Benz's vastly improved 1,000 hp DB600A series engine, but prioritise fighter jet development. As such, the Do 17M was fitted with a Bramo 323 Fafnir nine-cylinder air-cooled radial piston engine with 900 hp, while the Do 17P was fitted with the BMW 132N series.

These newer designs gained greater interior space, accommodated stores over 2,200 pounds, and improved defensive weapons based on combat experience gained in the all-important Spanish Civil War. These versions are also limited production aircraft.

The Do 17S came next, a high-speed reconnaissance platform that never made it into a production model. Another reconnaissance version, the Do 17U, produced three prototypes and twelve operational models, and introduced (like the Do 17S) a stepped cockpit, increasing the interior space and thus increasing the operator to five.

Both are equipped with the Daimler-Benz DB600 series and improved defensive armament.

The Do 17Z will prove to be the final model of the Do 17 series. It retains the modifications of the Do 17S and Do 17U, but installs a Bramo Fafnir radial piston engine.

These engines proved to be underpowered at full airframe combat loads, so Bramo offered their supercharged 323P engines, each producing 1,000 horsepower. From there, the Do 17Z was further developed into a multi-role bomber/reconnaissance platform, allowing the Luftwaffe to use a single airframe simultaneously.

Overall, the Do 17Z includes the Do 17Z-1 bomber with the Bramo 323A-1 Fafnir Meridian, the Do 17Z-2 with the 1,000 hp Bramo 323P Fafnir Meridian, the Do 17Z-3 dual-action bomber/reconnaissance model, the Do 17Z -4 dual control trainers and Do 17Z-5 reconnaissance platform with extended range and dedicated water equipment.

Invasion of Poland

When Germany pledged to invade Poland on September 1, 1939, its number in 9 battle groups totalling 370 Do 17s ensured the ubiquity of this type in operations against Polish forces. Air superiority was quickly gained, and the Do 17 could operate relatively safely over Poland, often engaging ground targets at lower, more accurate altitudes.

The first target of the Do 17 Fluggruppen was the railway bridge near Dirschau, which was bombed by the Do 17Z elements of III/KG 3. During these early stages, the Do 17 accounted for a large portion of the Luftwaffe's offensive strikes.

The Fall of France and the Battle of Britain

Do 17s were used in a similar role during the French invasion, these were mostly Do 17Z models. Dorniers were used in all major German campaigns, including raids on Allied warships in the English Channel. The last viable Allied forces were driven out of France through the port city of Dunkirk.

France was not sufficiently equipped, both militarily and politically, to deal with a German attack, and with the surrender of France, the preparations for the Battle of Britain were ready.

If the land invasion of the British Isles continued, air superiority would have to turn to the Germans again. At this point, however, the Do 17 began to show its limitations, and it was born out of a need for a delivery aircraft.

Early in her career, she was faster than any fighter deployed by her foes, but by 1940 the genre had largely prevailed in its original form from the late 1930s. This gave the Allies time to provide more powerful combat mounts in the British Hawker Hurricanes and Super Navy Spitfires.

The era of Do 17 is coming to an end.

The Battle of Britain officially began on July 10, 1940, with approximately 212 Do-17 bombers and reconnaissance models available. The British bravely defended fighter jets and anti-aircraft defenses against plundering German troops. The Do 17 is still a formidable mount, but its sleek airframe design limits its bomb-loading capabilities. In addition, her bottom turned out to be vulnerable to ground-based anti-aircraft guns.

While newer Allied fighters have reasonable speed, they can match and often exceed the performance they were once lauded for. She still has inherent defensive mobility, can dive to evade enemy combatants, and her defensive weapons still serve to contain her to some extent.

In the end, however, the determination of the British and the skills of their pilots, communications and ground crews all succeeded in taking control of the German war machine. Hitler indefinitely postponed any possible invasion of the British mainland until the near future.

Yugoslavia and Croatia

Yugoslavia became early export users of Do 17, they received Do 17M as Do 17Kb-1, Do 17Kb-2 and Do 17Kb-3. The Do 17Kb-1 was a dedicated bomber model, while the Do 17Kb-2 and Do 17Kb-3 were reconnaissance aircraft. The main difference between these and the German brand is the use of a French Gnome-Rhone 14 Na/2 radial piston engine and a Belgian Fabrique-National FN Browning machine gun. Structurally, the Yugoslav version was done in the early designs of the prototype, but largely followed the German route.

At least 20 Do 17 aircraft were delivered to the Yugoslav Air Force while local production licenses were obtained. This production took place at the National Aircraft Factory in late 1939. The imported Yugoslav Do 17Z model was called "Do 215".

The Germans eventually targeted Yugoslavia and went to war on April 6, 1941. The attack also included troops from Italy, Albania, Hungary and Bulgaria. The war continued until April 17, 1941, and resulted in a complete conquest. Yugoslavia was occupied and its factories were controlled by Germany. At least 70 Do 17s were available during the war, but 26 were destroyed by the Luftwaffe while others fled tragically to other countries.

The independent state of Croatia was born from the ashes of Yugoslavia, inheriting the Do 17s.