2D profile illustration of the S-31 Kurowashi fictional aircraft, as featured in a 1944 or 1945 issue of “Sora” magazine. Ronnie Olsthoorn Aviation Art.
2D profile illustration © Ronnie Olsthoorn Aviation Art
In April 1941 “Sora” magazine from Japan published an article about several future aircraft designs, which subsequently ended up in allied intelligence reports at the start of WW2 as potential opponents! However none of the designs were real, and soon forgotten. Late in the war “Sora” magazine published an article about the S-31 Kurowashi (Black Eagle) heavy bomber, which was so fantastical it apparently failed to attract allied attention. The Kurowashi was to be a heavy bomber, powered by four 2500 hp engine in tandem push-pull arrangement, driving contra-rotating propellers. With a top speed of 690 kph it could carry no less than 8000 kgs of bombs and had a defensive armament of eight 7.7 mm machine guns and four 23 mm cannon, arranged in wing-mounted remote-operated turrets.
Ronnie notes: In 2009 I was commissioned to create a profile of this aircraft for the propaganda aircraft section of Midland Publishing’s “Japanese Secret Projects” by Edwin Dyer. I’ve given it the colours of the 2nd Chutai, 62nd Sentai, Japanese Army Air Force, which in reality flew Ki-21 ‘Sally’, Ki-49 ‘Helen’ and Ki-67 ‘Peggy’ bombers during WW2.
Type: Heavy Bomber
Crew: Five
Powerplant: Four 24-cylinder, liquid-cooled X-engines, each developing 2,500hp, each pair driving two, metal, 3-bladed contra-rotating propellers
Dimensions
Span: 32.82m/107.7ft
Length: 21.09m/69.2ft
Height: 5.88m/19.3ft
Wing Area: 133.00 sq.m/1,431.6 sq.ft
Weights
Loaded: 17,850kg/39,352lb
Performance
Max speed: 690km/h/429mph
Cruise speed: 589km/h/366mph
Landing speed: 145km/h/90mph
Range: 5,900km/3,666 miles
Ceiling: 15,100m/49,540ft
Fuel Weight: 8,000kg/17,636lb
Armament
Eight 7.7mm machine guns and four 23mm cannons; up to 8,000kg (17,636lb) of bombs
The plane had a novel defensive armament scheme, using remote fired ball turrets in the leading and trailing edge of the wings.
Japanese Secret Projects: Experimental Aircraft of the IJA and IJN 1939-1945
Japanese Secret Projects: Experimental Aircraft of the IJA and IJN 1939 – 1945, Book 2