Junkers Ju 86

Junkers
Industry	Aircraft manufacturing
Founded	1895
Founder	Hugo Junkers
Headquarters	Dessau, Germany
Products	Aircraft, including Junkers Ju 86

The Junkers Ju 86 is a monoplane developed in the mid-1930s by the German manufacturer Junkers, designed both as a bomber and a civilian airliner. Conceived to fulfill a requirement for a modern twin-engine aircraft capable of serving dual roles—as a fast airliner and as a bomber—it featured an all-metal, low-wing design initially powered by innovative Junkers Jumo 205 diesel engines, chosen for their superior fuel economy. Departing from earlier Junkers designs, it employed smooth metal skin rather than the traditional corrugated surface. The bomber versions housed bombs vertically within four fuselage compartments situated behind the cockpit, while the civilian airliner model replaced these with seating accommodations for up to ten passengers. The first prototype took flight on 4 November 1934, equipped with Siemens SAM 22 radial engines; the initial civil-configured prototype followed on 4 April 1935.

Civilian Ju 86 aircraft operated with several airlines, including Germany’s national carrier Deutsche Luft Hansa, Manchukuo National Airways, South African Airways, Iberia Airlines, and AB Aerotransport. After the onset of the Second World War, numerous civilian units were converted for military purposes. The Ju 86 entered combat service with multiple air forces, making its military debut during the Spanish Civil War under the Condor Legion. The Luftwaffe deployed Ju 86s in the invasion of Poland, but retired diesel-powered variants early on, relegating radial-engine models primarily to training duties. In late 1942, Ju 86s were recalled from training roles to undertake transport missions aimed at resupplying the encircled German 6th Army at Stalingrad; however, this operation was curtailed due to Soviet advances.

The Ju 86P model, introduced in early 1940, incorporated extended wings, a pressurized cabin, and turbocharged Junkers Jumo 207A-1 diesel engines. This enabled high-altitude reconnaissance and nuisance bombing raids over England until countered by modified Spitfires. An advanced variant, the Ju 86R, was developed to reach even greater altitudes with enlarged wings and new engines but remained at the prototype stage. Today, just one Ju 86 is preserved and exhibited at the Swedish Air Force Museum near Linköping.

Background

The inception of the Junkers Ju 86 dates back to the secretive expansion of the Luftwaffe during the mid-1930s. In 1934, the German Reichsluftfahrtministerium (RLM) collaborated with national airline Deutsche Luft Hansa to draft specifications for an aircraft intended to serve dual roles as a fast twin-engine airliner and medium bomber. Although separate civil and military variants were anticipated, military needs took precedence when requirements conflicted.

Initial contracts for five prototypes each (three military and two civilian) were awarded to two manufacturers: Junkers with their Ju 86 and Heinkel with the He 111. Junkers opted for a low-wing twin-engine monoplane featuring all-metal stressed skin construction, replacing their usual corrugated covering with smooth metal panels to minimize aerodynamic drag. Power was supplied by Junkers Jumo 205 diesel engines—remarkable at that time for their fuel efficiency despite added weight—making the Ju 86 among the earliest production aircraft powered by diesel engines.

The tapered wings incorporated two main spars alongside an auxiliary spar, equipped with characteristic Junkers control surfaces hinged beneath the trailing edge—the outer sections functioning as ailerons and inner sections serving as flaps. The landing gear consisted of retractable main wheels attached at wing roots with a narrow track and a fixed tailwheel; twin vertical stabilizers with rudders completed the empennage design.

The bomber’s crew included four members: pilot, navigator, radio operator/bombardier, and gunner. Defensive armament comprised three machine guns positioned in the nose, dorsal turret, and retractable ventral mount. Bombs were stored vertically within four fuselage cells located behind the cockpit. In contrast, the airliner version replaced bomb compartments with seating for ten passengers and relocated fuel tanks from within the fuselage to wing-mounted positions.

Initial flights

The Ju 86ab1, configured as a bomber, took to the skies for the first time on 4 November 1934. Initially, it was equipped with Siemens SAM 22 radial engines because the Jumo 205 engines were not yet available. Early testing revealed issues with control and stability, which led to subsequent design adjustments. The second bomber prototype followed in January 1935, and the first civil prototype appeared in April of the same year. Later prototypes incorporated redesigned wings that expanded the wing area towards the tips.

By the end of 1935, production of pre-series military and civilian versions commenced, with full-scale manufacturing of the Ju 86A-1 bomber beginning in April 1936. To enhance stability, a dorsal fin was added to the Ju 86C variant. Production soon transitioned to the Ju 86D model, which featured a modified tail cone that improved stability and increased fuel capacity by nearly half compared to the A series. Due to growing demand in the late 1930s, competitor Henschel was brought in to assist with manufacturing.

Operational deployment during the Spanish Civil War revealed shortcomings of the Jumo-powered Ju 86, as its diesel engines proved less reliable under combat conditions than those on the Heinkel He 111. As a result, plans for mass production were curtailed. One Ju 86 was converted to utilize radial engines for export evaluation, demonstrating better reliability. From then on, production concentrated on the BMW 132-powered Ju 86E model through 1938. Although production halted, surplus components allowed assembly of as many as 1,000 additional aircraft.

While its role as a bomber diminished, Junkers persisted in evolving the Ju 86 into a high-altitude reconnaissance and bombing platform. The Ju 86P variant featured an extended wingspan, a pressurized cockpit, turbocharged Jumo 207A-1 diesel engines, and a two-person crew arrangement, enabling operations above 12,000 meters (39,000 feet), effectively beyond enemy fighter reach. This model was created by converting existing Ju 86D airframes.

In early 1942, Junkers introduced the Ju 86R with larger wings and more powerful engines capable of reaching altitudes up to 16,000 meters (52,500 feet) to evade advanced interceptor aircraft. A limited number entered Luftwaffe service in 1943. More advanced versions such as the Ju 86 R-3 and Ju 186 remained conceptual and never advanced beyond design phases.

Export models

Civilian versions launched in 1936 were designated as Ju 86Z and came in three engine variants. The Jumo-powered Ju 86Z-1 (previously known as B-0 or C-1) was sold to Swissair (one unit), Airlines of Australia (one unit), and LAN-Chile (three units). The BMW 132H-powered Ju 86Z-2 was delivered to Deutsche Luft Hansa (two units) and Manchukuo Air Transport (five or more units). The Pratt & Whitney R-1690 Hornet-powered Ju 86Z-7 went to Sweden's AB Aerotransport (one mail plane), Lloyd Aéreo Boliviano (three units), and South African Airways (SAA) (seventeen units). The aircraft operated by ABA later served with the Swedish Air Force under the designation Tp 9 until 1958. Although SAA originally planned to equip their fleet with Rolls-Royce Kestrel engines, six aircraft were refitted with Hornet engines before delivery; all others were powered by Hornets.

The Ju 86K export variant was produced under license in Sweden by Saab as the B 3 model, fitted with Bristol Mercury XIX radial engines delivering 905 hp. Several remained active within the Swedish Air Force until 1958. Some units were adapted for radio interception duties.

Operational history

The Condor Legion deployed the bomber for testing during the Spanish Civil War. In early 1937, four Ju 86D-1 units were delivered; after sustaining losses and accidents, two were transferred to the Nationalist air force, where they remained active until the conflict concluded. Overall, the Ju 86 was considered less capable than the Heinkel He 111.

At the outbreak of World War II, a single Gruppe equipped with Ju 86 bombers (III KG 1 "Hindenburg") took part in the invasion of Poland but was soon replaced. The diesel-powered Ju 86A and D variants were rapidly phased out, while the radial-engine Ju 86E and G versions were reassigned to bomber training schools. Early Luftwaffe campaigns saw commanders divert Ju 52 transports and instructors from training units, resulting in a shortage of pilot instruction. Although Lieutenant Colonel Paul Deichmann suggested producing dual-control Ju 86 trainers to alleviate this, Hermann Göring rejected expanding air transport capabilities.

By late 1942, all available aircraft—including Ju 86s—were pulled from training duties to bolster Luftwaffe transport operations supplying the encircled 6th Army at Stalingrad. Two transport Gruppen operated a fleet of 58 Ju 86s from Tatsinskaya Airfield but incurred severe losses—42 aircraft lost by January 1943—and were withdrawn following Soviet capture of Tatsinskaya. Remaining aircraft returned to training assignments.

Among Allied operators, South African Airways converted seventeen early-model Ju 86s into militarized bombers for coastal patrol and East African Campaign missions starting June 1940. As more modern aircraft became available, these Ju 86s shifted to reconnaissance roles before being retired in September 1942.

Hungary utilized Ju 86 bombers during the Slovak–Hungarian War in 1939 and initial World War II operations but replaced them with Caproni Ca.135 bombers by mid-1941. During Operation Barbarossa, Ju 86s supported the Hungarian Fast Corps but were withdrawn from frontline duties by 1942.

In January 1940, the Luftwaffe assessed the prototype Ju 86P, designed to operate above 12,000 meters (39,000 feet), beyond the reach of enemy fighters. This capability spurred development of interceptors such as the British Westland Welkin and Soviet Yakovlev Yak-9PD. Following successful trials, approximately forty older bombers were converted into pressurized variants: the Ju 86P-1 high-altitude bomber and the unarmed two-man Ju 86P-2 photo-reconnaissance aircraft.

The Ju 86P proved effective over Britain, the Soviet Union, and North Africa. Reconnaissance missions over Britain ceased after Operation Barbarossa commenced in mid-1941. By mid-1942, pressurized bombers conducted low-impact nuisance raids over southern England, each carrying a single small bomb; one such raid notably caused significant casualties in Bristol. RAF Spitfire Mk IX fighters intercepted these bombers; after losses including one on September 12, 1942, these raids ended. In August 1942, a modified Spitfire Mk V successfully shot down a Ju 86P over Egypt at an altitude of 14,500 meters (49,000 feet). Following additional losses, the Ju 86P was withdrawn from service in 1943.

Between 1943 and mid-1944, a single unit operated the higher-altitude capable Ju 86R variant.

Surviving Aircraft

At present, only a single Junkers Ju 86 is preserved. Manufactured in Germany and delivered to Sweden in 1938, this aircraft remained in service until 1958 and featured in the 1955 motion picture Des Teufels General. It is currently exhibited permanently at the Swedish Air Force Museum located near Linköping.

Prototypes

Ju 86abl: Initial bomber prototype.
Ju 86bal: Second prototype designed for transport.
Ju 86cb: Third bomber prototype.
Ju 86V4: Prototype developed for the Ju 86B commercial transport variant.
Ju 86V5: Prototype intended for the Ju 86A bomber model.

Production Versions

Ju 86A-0: Thirteen pre-production bomber units.
Ju 86A-1: First operational bomber model.
Ju 86B-0: Seven pre-production transport aircraft.
Ju 86C-1: Six transports built for Deutsche Luft Hansa, equipped with twin Junkers Jumo 205C diesel engines.
Ju 86D-1: Bomber variant.
Ju 86E-1: Luftwaffe bomber powered by two BMW 132F radial engines.
Ju 86E-2: Enhanced model featuring BMW 132N radial engines.

Ju 86G-1: Equipped with a rounded glass nose section.
Ju 86K-1: Export version supplied to South Africa and Sweden.

Ju 86K-2: Exported to Hungary.
Ju 86K-4: Swedish export model similar to K-1 but fitted with two Bristol Pegasus III radials.
Ju 86K-5: Bomber constructed in Sweden, powered by two Bristol Pegasus XII radials.
Ju 86K-6: Exported to Chile.
Ju 86K-7: Exported to Austria and Portugal, featuring BMW 132 radial engines.
Ju 86K-13: Swedish-built bomber equipped with either Swedish or Polish Pegasus engines.
Ju 86P-1: High-altitude bomber variant with dual Jumo 207 diesel engines and turbochargers.
Ju 86P-2: High-altitude photo reconnaissance bomber using the same engines as the P-1 model.
Ju 86R-1: High-altitude photo reconnaissance aircraft retaining Jumo 207 powerplants.
Ju 86R-2: High-altitude bomber configuration.
Ju 86R-3: Fitted with two Jumo 208 engines.
Ju 86Z series: Civilian export variants.

Concepts

Ju 186: Planned four-engine high-altitude bomber that was never constructed.
Ju 286: Proposed six-engine high-altitude bomber, not realized.
K 85: Conceptual torpedo bomber intended for the Swedish Air Force.

Military Users

Austria

Austrian Air Force

Bolivia

Bolivian Air Force

Chile

Chilean Air Force

Germany

Luftwaffe

Hungary

Royal Hungarian Air Force

Portugal

Portuguese Air Force

Romania

Romanian Air Force

South Africa

South African Air Force: Operated a fleet of eighteen aircraft comprising seventeen Ju 86Z and one Ju 86K (originating from South African Airways), utilized by both 12 Squadron and 16 Squadron.