Junkers Ju 390
The Junkers Ju 390 was a German six-engined long-range aircraft of the Second World War, a stretched derivative of the Ju 290 built for the Amerikabomber programme, which sought a bomber able to strike New York from bases in Europe. The first prototype flew on 20 October 1943 and performed well, but the production contracts were cancelled in mid-1944, and whether the second prototype was ever completed is disputed. The type is best known for the claim that one of its flights reached to within 12 miles of New York in 1944: the story traces to wartime prisoner interrogations, and later research has rejected it.
Why It Mattered
The Ju 390 was Junkers' entry in the Amerikabomber competition, Germany's search for a bomber that could reach New York from bases in Europe. The Air Ministry's request set the scale of the ambition: a range of 7,450 miles. Of the designs submitted, Junkers' was judged the easiest to produce, because it simply stretched the Ju 290. Only the first prototype is known to have flown, the follow-on orders were never built, and the type never entered service. What made the Ju 390 famous came afterwards: a claim, repeated for decades, that one of its flights had reached to within 12 miles of New York. That claim is contested: it traces back to wartime prisoner interrogations, and the aircraft's documented test programme, spent in Germany and Prague, contains no such flight.
Design Notes
The Ju 390 was a lengthened, six-engined development of the Ju 290, created by inserting extra inner-wing segments into the earlier aircraft's wing and new sections into its fuselage. The first prototype was not even a new airframe: it was converted from the Ju 90 V6, which had earlier flown with a civil registration. Six BMW 801E radials, rated at 1,970 hp each for take-off, gave the aircraft two more engines than the Ju 290. Published figures for the planned production version, the Ju 390 A-1, give a span of 50.32 metres and a length of 34.20 metres, though reference works disagree on the type's exact size, and these are figures for a version that was never built. The A-1 was to have had a fuselage 2.5 metres longer than the first prototype's, maritime-search radar, and cannon armament; published accounts differ on the gun fit, one giving five 20 mm cannon, another four cannon and three machine guns.
Operational History
The first prototype was largely assembled at Junkers' Dessau plant, and it flew for the first time on 20 October 1943. The aircraft performed well enough to win an order in early 1944 for six further prototypes, V2 to V7, and 20 examples of the intended A-1 production version. On 26 November 1943 the V1 had been shown to Adolf Hitler at Insterburg, East Prussia, among many other new aircraft. Test pilot Hans-Joachim Pancherz's logbook then places the V1 at Prague, where its test flights continued until March 1944 and included trials of aerial refuelling. Some accounts say a Ju 390 was delivered in January 1944 to Fernaufklärungsgruppe 5 at Mont-de-Marsan, in France, for trials over the Atlantic; Kössler and Ott state that no Ju 390 was assigned to that unit, so the delivery is contested. The contracts for the V2 to V7 and the production aircraft were cancelled on 20 June 1944, all work ceased that September, and that summer a decree cancelled work on bomber aircraft in favour of fighters. The second prototype's fate is disputed: History of War judges it probably completed, but Heinrich Hertel, Junkers' chief designer, told British authorities in 1945 that it had never been completed. Pancherz stated in 1980 that only the first Ju 390 flew, which contradicts Friedrich Georg's claim that the V2 was flown at Rechlin in February 1945. The V1 returned to Dessau in November 1944, was stripped of parts there, and was destroyed in late April 1945 as the US Army approached.
Afterlife
No Ju 390 survives: the V1 was destroyed at Dessau, and both aircraft were scrapped before the war ended, in History of War's account. The New York story entered print in November 1955, when a letter in RAF Flying Review claimed that two Ju 390s had flown to America, including an hour over New York City; the magazine's editors were sceptical of the claim. In the version William Green published, a single Ju 390 delivered to Fernaufklärungsgruppe 5 in January 1944 had made a 32-hour reconnaissance flight to within 19 km (12 miles) of the coast north of New York. British authorities had already rejected the story just after the war, yet it was repeated in many books after the Flying Review account, generally without sources, and later authors cited Green's books in turn. Aviation historian Kenneth P. Werrell traced the story to two British intelligence reports from August 1944, based in part on prisoner interrogations, and the Long Island photographs those reports claimed have never been found. Kössler and Ott reached the same conclusion from the aircraft's movements: at the time of the alleged flight the only Ju 390 was in Prague, not France, and in their judgement it could not have lifted the fuel the flight required.