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Ju89

Ju-89 Ural Bomber

Ural Bomber was an aircraft design competition in pre-war Germany to develop a long-range bomber for the  Luftwaffe. The design competition was created and led by General Walther Wever in the early 1930s.
The Ju-290 itself evolved from an aircraft lineage which traced back to the four engine Ju-89 "Ural Bomber," first flown in April 1937 by Junkers test pilot Peter Hesselbach.


Artist's impression of the Ju89 Bomber

The Ju 89 design was subjected to extensive wind tunnel testing. It was designed for a cruise speed of 400 km/h (250kts) & maximum speed of 450 km / h (480kts) with corresponding engines of 4 x 1,250 hp). The Ju89 would boast a bomb load of 2-6 metric tons and a range of 1,500 km to 4,000 Km These values ​​were exceptional and unprecedented at the time. The swept back wing was designed to allow high speed, but also stability when bomb release cause sudden shifts in the centre of gravity.

Draft plans for the Ju 89 emerged 25 March 1935 (LC 1137/35) under joint direction of Bernhard Cruse.
Fritz Freundel and Johannes Haseloff as design leaders. In addition to construction of the Ju 87, Ju 88 & future EF-61 high altitude bomber, construction of the Ju 89 was added in 1936. Junkers was thus far and wide the only aircraft factory in the world, which was able to construct four totally different types of aircraft in parallel.
 

Three Ju-89 prototypes were built in response to the visionary strategic requirement by Marshal of Air Staff General Walther Wever, however only two actually flew before the Ural Bomber project was abandoned. When Wever died in an accident in June 1936
Albert Kesselring, Weaver's successor, believed what Germany required were more fighters and tactical bombers.

By Bundesarchiv, Bild 141-0068 / CC-BY-SA 3.0, CC BY-SA 3.0 de, https://commons.wikimedia.org/w/index.php?curid=5418721

There was bitter rivalry in the Luftwaffe by proponents of dive bombers such as Ernst Udet & Hans Jeschonneck against conventional bombers. Dive bomber proponents demanded that all bombers must be capable of dive bombing their targets. The Ural Bomber contest called for an aircraft capable of delivering 1,000kg of bombs over 1,000 kilometres.

Wever died when the He-70 biplane in which he took off from Dresden with on 3 June 1936, stalled & flipped on take off. The Ural Bomber program ended almost overnight.
Albert Kesselring took over Wever's position in the Luftwaffe, abandoning most of his designs and turning others into tactical bombers. Literally the next morning RLM issued a new requirement for the so called type A bomber, including a demand for dive bombing capability. Ultimately the troubled Heinkel He-177 won the new competition.

Upon the advice of Kesselring, Udet and Milch, Reichsmarshal Herman Goering ordered the Ju89 project to be abandoned. Kesselring was a vocal supporter of twin engine bombers and backed up Udet who preferred dive bombers. This was why a foolhardy decision was made to convert the Ju88 into a dive bomber. Milch on the other hand being more pragmatic wanted the project cancelled simply because at that stage the German aero industry was incapable of mass producing a large fleet of heavy bombers. Later in the war however Heinkel with the help of slave labour disproved Milch's concern.

Milch argued that Dural Aluminum production did not seem sufficient to use in such a large aircraft. The Ju89 consumed twice as many engines and three times as much Dural Aluminum as Ju 88 or He 111 light bombers. In addition, large airplanes were much easier to shoot down than smaller ones. In the Grand Bomber design, there seemed no decisive advantage, except that it had a greater range.

Goering shelved the Ural Bomber project. He later said, "The Fuhrer will never ask me how big our bombers are, but how many we have."


Only two Ju-89 prototype bombers were flown, but it set several payload/altitude records reaching 7,242m (23,750ft) with a payload of 10,000kg (22,000lb) demonstrating a range of 2,980km (1,862 miles). The relatively under-powered Ju-89 was powered by four 750 hp Daimler Benz DB 600A engines. The Ju-89's performance was roughly comparable, but inferior to the British Short Stirling bomber designed much later.
One could speculate that such a bomber aircraft in German hands by 1939 would have changed the War.

On 11th April 1937, Ju89 prototype D-AFIT (V1, c/n 4911) was first flown by Peter Hesselbach. Two weeks after the first flight, on April 29th 1937 all further development of strategic bombers was cancelled by RLM.

The
second Ju89 prototype D-ALAT was finished in July 1937, but the third prototype V3 was stopped after the program was cancelled. Both flying  prototypes were used by Junkers for extensive flight tests to get experience about the stability and flight controls of large aircraft.


Ju-89 V2 General Data:

Crew: Five
Length: 26.49 m (86 ft 11 in)
Wingspan: 35.25 m (115 ft 8 in)
Height: 7.60 m (24 ft 11 in)
Wing area: 184 m² (1,979 ft²)
Empty weight: 17,000 kg (37,480 lb)
Loaded weight: 20,800 kg (50,266 lb)
Max. takeoff weight: 27,800 kg (61,160 lb)
Powerplant: 4 × Daimler-Benz DB 600A, 560 kW (750 hp) each


Performance Data

Maximum speed: 386 km/h (241 mph)
Range: 2,980 km (1,862 mi)
Service ceiling: 7,000 m (22,960 ft)



On June 4th 1938 the Ju89 achieved a new Payload/Altitude World Record with the second prototype D-ALAT with 5000 kg payload at an altitude of 9312 m. ( 4000 meters more than a Short stirling with the same payload) On June, 8th 1938 he reached with the same aircraft an altitude of 7242 m with 10000 kg. In late 1938 both aircraft were transferred to Luftwaffe, where they were used as heavy transport aircraft until summer 1939, after which they were probably scrapped. Some sources however also mention, that both aircraft were still used during 1940 in Norway with the special  transport unit KGrzbV 105.


Ju89 V1 and V2 prototypes were abandoned by 1940, then scrapped. The original V3 prototype was rebuilt as a transport aircraft in 1938, becoming the Ju90 fore runner to the Ju290.
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