Junkers Ju 86

It would be fair to say that the Junkers Ju 86 was already obsolescent at the beginning of World War 11, and was accepted rather grudgingly by the Luftwaffe, which preferred the Heinkel He 111. It is all the more surprising, therefore, that within two years the type was operating in the reconnaissance role at higher altitudes than other Luftwaffe aircraft could reach.

Like the contemporary He 111, the Ju 86 was developed as an airliner and bomber, and five prototypes of each were ordered in 1934. The Junkers aircraft flew five months later, four months ahead of its competitor, and had been designed around the new Junkers Jumo 205 diesel engine.

Initial flight trials were disappointing, handling in particular being poor, and during subsequent modifications (which may have improved but not eradicated the problems) gun positions were installed. The third prototype was completed as a bomber and flew in January 1935, four months before the second prototype that was built as a commercial aircraft with 10 passenger seats. The fourth prototype, destined to become the first definitive Ju 86B airliner, flew in May 1935, followed three months later by the fifth prototype, the production prototype for the Ju 86A bomber.


A Junkers Ju 86D-1 medium bomber of 5/Kampfgeschwader 254, based at Eschwege in September 1937

 

Production at Junker's Dessau factory began on both versions in late 1935 with an initial batch of 13 Ju 86A-0 and seven Ju 86B-0 pre-production aircraft, the first deliveries being made in February 1936. Bombers carried a crew of four and had a defensive armament of three machine-guns. The first export delivery was of a Ju 86B-0 to Swissair in April 1936 for night mail service, and the balance of six of these pre-production aircraft went to Lufthansa. In February 1937 a second aircraft went to Swissair under the export designation Ju 86Z-1, but when re-engined subsequently with BMW 132De radials it was redesignated Ju 86Z-2. Lufthansa also received an additional six aircraft in 1937 and these, powered by Jumo 205C diesel engines, had the designation Ju 86C-1.

Junkers had received some export orders for military models with alternative powerplants. Sweden acquired three Ju 86K-1 aircraft with 875 hp (652 W) Pratt & Whitney Hornet radial engines, and subsequently 16 more were built under licence by SAAB in Sweden and powered by either Swedish or Polish built Bristol Pegasus engines, both variants having the designation Ju 86K-13. Other versions of the Ju 86K were sold to Chile, Hungary and Portugal and the (wit Gnome-Rhone, Bristol Pegasus 111 or Swedish built Pegasus XII engines) had the respective designations Ju 86K-9, Ju 86K4 and Ju 86K-5. Hungary later assembled 66 more aircraft under licence, powered by licence-built Gnome-Rh6ne radials, and these had the designation Ju 86K-2.

Meanwhile, modifications to the military models resulted in the Jumo 205C-engined Ju 86D-1, five of which served with the Legion Condor during the Spanish Civil War, but the diesel engines were not standing up well to combat conditions and the aircraft had proved markedly inferior to the He 111. Disenchantment with the Ju 86D and the very poor serviceability of its engines led the Luftwaffe to make savage and sudden cuts in the Junkers programme and the diesel engines were dropped. Instead, the 810 hp (604 kW) BMW 132F radial was installed, resulting in the designation Ju 86E-1, this type being followed by the Ju 86E-2 with uprated 865 hp (645 kW) BMW 132Ns. Performance showed little improvement but reliability was greatly improved.

In 1938, in an attempt to improve pilot visibility, Junkers redesigned the entire nose section, bringing the pilot farther forward and shortening and lowering the nose to provide a fully glazed enclosure of more streamlined contours. The revisions were included on the final 40 production Ju 86E-2s under the designation Ju 86G-1, and manufacture of the Ju 86 ceased in 1938 with a total of about 390 aircraft (excluding licence- manufacture). Withdrawal of the type from Luftwaffe front-line service began in late 1938, but at various times during World War 11 it was found necessary to recall groups from training establishments, for instance in the relief of Stalingrad, but casualties were heavy. In spite of its unsuitability for front-line service, the Ju 86 still had one useful (and unique) role to fill for the Luftwaffe.

Junkers had been experimenting for some time with a high-altitude version of the Jumo diesel engine, together with pressure cabin design, and in September 1939 submitted proposals for a high-altitude reconnaissance version of the Ju 86. The go-ahead was given, and two Ju 86D airframes were converted, gun positions faired over (since no fighter would be able to reach the aircraft at its operation al altitude) and a two-seat pressure cabin was fitted. The prototypes flew in February and March 1940 as Ju 86P aircraft, and reached altitudes of more than 32,810 ft (10000 m). A third prototype with wing span increased by 10 ft 2 in (3.10 m) reached 39,700 ft (12100 m), and the success of the trials earned an order for the conversion of 40 Ju 86Ds to Ju 86Ps. Two models were built the Ju 86P-1 bomber with a load of 2,205 lbs (1000 kg) and the Ju 86P-2 reconnaissance aircraft with three cameras. One of the prototypes flew a reconnaissance mission over the UK at 41,010 ft (12,500 m) in the summer of 1940 and was undetected, and other production models both followed this over the UK and USSR.

While standard Allied fighters were unable to reach them the Ju 86Ps remained unscathed, but in August 1942 a stripped-down Spitfire Mk V caught a Ju 86P at 37,000 ft (11275 m) over Egypt and after a chase to 42,000 ft (12800 m) shot it down. In an effort to gain more altitudes, a higher aspect ratio wing was designed, increasing the span to 104 ft 113/4 in (32.00 m), and uprated Jumo engines with four- blade propellers were installed. Two versions were again built, the Ju 86R-1 reconnaissance aircraft and the Ju 86R-2 bomber, each comprising conversions of the respective Ju 86P types. Only a few aircraft reached service, but during tests an altitude of 47,250 ft (14400 m) was reached. Further development of the Ju 86R-3 with 1,500 hp (1119 kW) supercharged Jumo 208s and designed to reach 52,500 ft (16000 m), and of a proposed Ju 186, with four Jumo 208s or two Jumo 2 18s (which were coupled Jumo 208s) was abandoned. Probably the last surviving Ju 86s were those with the Swedish Air Force which completed their service as transports in 1956. One is preserved in the Swedish Air Force museum.

Ju 86abl/bal/cb

The Junker Ju 86abl was the first bomber prototype. It was powered originally by Siemens SAM 9 radial engines. The Ju 86bal was the second prototype developed as a transport, with Junker Jumo 205C diesel engines. The Ju 86cb was the third prototype, developed as a bomber, similar to the Ju 86abl, but with Junkers Jumo 205C diesel engines.

Ju 86V-4/V-5

The Ju 86V-4 was a production prototype for the commercial Ju 86B, and the Ju 86V-5 was the prototype for the Ju 86A bomber.

Ju 86A-0/A-1
 

The Ju 86A-0/A-1 totalled 13 aircraft designed for use as bombers with the Luftwaffe.

Ju 86B/B-0

Designed for civilian use. The Ju 86B was a transport produced for use by Swissair. These were delivered in April 1936. The Ju 86B-0 was made of up of seven pre-production aircraft for use by the Luftwaffe as transports.

Ju 86C-1

Six transport aircraft for Lufthansa with Junker Jumo 205C diesel engines.

Ju 86D-1

A bomber version with improved Junkers Jumo 205C engines, five of which served with Legion Condor during the Spanish Civil War, but the powerplant did not stand up well to combat conditions and the aircraft soon proved to be markedly inferior to the He 111.

Ju 86E-1/E-2
 

The Luftwaffe's dissatisfaction with the capability of the Ju 86D led to the development of the far more reliable Ju 86E-1 with BMW 132F radial engines. The Ju 86E-2 had BMW 132N engines.

Ju 86G-1

Improvements introduced during production brought redesignation of the last 40 Ju 86E's to be produced as Ju 86G-1 aircraft with round glazed noses. Production ended in 1938.

Ju 86K-1/K-2/K-6

The Ju86K-1 was the designation given to the export aircraft for South Africa and Sweden. The Ju86K-2 was a Saab built (under licence) aircraft for export to Hungary (66 aircraft total). The Ju 86K-6, also Saab built (under licence) were exported to Chile and Portugal.

Ju 86K-4/K-5/K-13

Similar to the Ju 86K-1 but with Bristol Pegasus Ill radial engines for Sweden (B 3A). Ju 86K-5 was similar to the Ju 86K-4 but with Swedish-built Pegasus XII engines (8 3B). The Ju 86K-13 was a Swedish-built bomber with Swedish and Polish-built Pegasus engines .

Ju 86P-1/P-2(Ju 86R-1/R-2)

In 1939 two Ju 86D airframes were used for conversion as the Jumo 207A engined prototypes of a high altitude version with a two seat pressurised cabin. Successful trials led to two initial production versions, the Ju 86P-1 (bomber), and the Ju 86P-2 (reconnaissance) aircraft. The Ju 86P-2 had a ceiling of about 42,000 ft (12800 m) and in an effort to gain more altitude a high aspect ratio wing spanning 104 ft 11 3/4 in (32.00 m) was introduced to produce the Ju 86R-1 (reconnaissance) version and the Ju 86R-2 (bomber) version.

Specifications (Junkers Ju 86D-1)

Type: Four Seat Medium Bomber

Design: Junkers design team headed by Dipl-Ing Zindel

Manufacturer: Junkers Flugzeug und Motorenworke AG; also built by Henschel, and built under licence by Saab, Sweden

Powerplant: Two 600 hp (447 kW) Junkers Jumo 205C-4 vertically opposed diesel engines.

Performance: Maximum speed 202 mph (325 km/h) at 9,840 ft (3000 m); cruising speed 177 mph (285 km/h) at 11,480 ft (3500 m); service ceiling 19,360 ft (5900 m).

Range: 932 miles (1500 km) with full bombload.

Weight: Empty equipped 11,354 lbs (5150 kg); with a maximum take-off weight of 18,078 lbs (8200 kg).

Dimensions: Span 73 ft 9 3/4 in (22.50 m); length 58 ft 7 1/2 in (17.87 M); height 16 ft 7 1/4 in (5.06 m); wing area 882.67 sq ft (82.00 sq m).

Armament: Three 7.92 mm (0.31 in) MG 15 manually aimed machine guns in nose, dorsal and ventral positions, plus an internal bombload of up to 1,764 lb (800 kg) carried internally.

Variants: Ju 86abl, Ju 86bal, Ju 86cb, Ju 86V-4, Ju 86V-5, Ju 86A-0, Ju 86B (commercial aircraft built for civilian use by Swissair), Ju 86B-0 (seven pre-production transports), Ju 86C-1, Ju 86D-1, (bomber) Ju 86E-1/E-2, Ju 86G-1, Ju 86K-4/K-5, Ju 86K-13, Ju 86K-1 (export variant for South Africa and Sweden), Ju 86K-2 (exported to Hungary by Saab), Ju 86K-6 (exported to Chile and Portugal by Saab), Ju 86P-1/P-2. Development of the Ju 86R-3 with super charger Jumo 208 engines and of the proposed Ju 186 four engine high altitude bomber based on the Ju 86 were abandoned. A six engined Ju 286 high altitude bomber did not progress beyond the the initial planning stage.

History: First flight (Ju86V-1) 4 November 1934; (V-5 bomber prototype) January 1936; (production D-1) late 1936; (P-series prototype) February 1940.

Operators: Germany (Luftwaffe, Lufthansa), Chile, Hungary, Manchukuo, Portugal, South Africa, Sweden.