R.Mikesh, A.Shorzoe Japanese Aircraft, 1910-1941 (Putnam)

Ozaki Soga-go Aeroplane

   This all-new aeroplane was built in the hangar at Tokorozawa almost in parallel with the Ozaki Tractor Biplane. As a result of accidents with the Kaizo Rumpler Taube belonging to the Imperial Flying Association, it re-equipped with Type Mo-4 trainers as an interim type until deciding in 1916 to have a new trainer designed and built. A major finance contributor was Ichiro Soga, a rice speculator in Dojima, Osaka, and therefore the Association named the new biplane the Soga-go. Chief engineer for the project was Yukiteru Ozaki with guidance from Army Lt Morikichi Sakamoto.
   Based on the Christofferson biplane, ailerons were installed on the upper wing only, originally extending from the trailing edge but later to be inset. A steel-tube frame was used for the forward part of the fuselage, and the undercarriage was taken from the Kaizo Rumpler Taube. When completed in April 1917 at Tokorozawa, it was not only larger than the Ozaki Tractor Biplane, but nearly twice the weight, yet with only 10hp more.
   At the request of Ichiro Soga the aeroplane was taken to Osaka where it was to make its first flight from the Joto Parade Grounds, following ceremonies for the occasion to be held on 22 April, 1917. But defects were discovered in the carburettor, the location of the fuel tank was faulty, and the undercarriage structure was felt to be inadequate. As a result, flying at Osaka was limited to one flight, and the aeroplane was returned to Tokorozawa for modifications.
   On 3 June, 1917, Ozaki participated in a flying exhibition in the 300th Year Fair at Nagaoka City, Niigata Prefecture, sponsored by the Association. Immediately after take off, the engine lost power and an emergency landing had to be made on a sand bank along the Shinano River, causing the aeroplane to turn over and sustain heavy damage. When repaired, a number of major modifications were made to the Soga-go, which included the fitting of smaller wings. It was then used by the Association exclusively under the name No.2 Soga-go.

   Single-engine biplane trainer. Mixed wooden and steel-tube fuselage and wooden framed wings with fabric covering. Pilot in open cockpit.
   90hp Austro-Daimler six-cylinder water-cooled inline engine, driving a two-bladed wooden propeller.
   Span, upper 12.98m (42ft 7in), lower 10m (32ft 9 1/2in); length 7.98m (26ft 2 1/4in); wing area 35sq m (376.75sq ft).
   Loaded weight 760kg (1,675Ib).
   Maximum speed 61 kt (71 mph); endurance 5 1/2hr.
   One built in April 1917.
   Data for the original Soga-go.

   Having limited success with these two aircraft, Ozaki retired from aviation and followed his father's political activities as his secretary. After 22 years and still highly respected in aviation circles, he flew in the ole remaining Type Mo-6 biplane at the First Aviation Day Pageant at Haneda Airport, on 28 September, 1940, making this the commemorative last flight of this early aircraft. In 1947, he was elected a member of the House of Counsellors, and when aviation activities resumed in Japan following the Pacific War he was appointed an advisor to Japan Air Lines, and vice-chairman to Japan Aviation Association. He died in june 1964 aged 76.