R.Mikesh, A.Shorzoe Japanese Aircraft, 1910-1941 (Putnam)
Nakajima Type 1 Biplane
A sign of Chikuhei Nakajima's independence in manufacture and design of aircraft was his intention that the company's first aeroplane design be directed toward sale to the Army. This aeroplane was designated Nakajima Type 1 Landplane. Design and draughting were mostly accomplished by Sakuma and Okui under Nakajima's close supervision. Tooling responsibility for aeroplane fittings was that of Kurihara. When fabrication was begun an additional fifteen to sixteen new craftsmen were hired for the project.
The Army showed early interest in the aeroplane by releasing to Nakajima two of its US-built 125hp Hall-Scott engines. When this first aircraft was completed in july 1918, it was described as the Nakajima Type 1-1, meaning Type 1, No.1. In configuration, it had a strong resemblance to the first Boeing aeroplane, the B & W of 1916. The Type 1-1 was flown for the first time by Yozo Sato from the Tone river-bed near Ohta which eventually became the Ojima Airfield. However, on that first flight, poor control caused it to crash immediately after take off. Sato survived, but the airframe was badly damaged.
In the meantime, design work had begun on the Nakajima Type 2. This was to be a seaplane intended to interest the japanese Navy. Materials were on hand for the first Type 2 but the aeroplane was never completed because they were diverted to repairing the damaged Type 1-1. After repair taking about twenty days, the aeroplane emerged as the Type 1-2. The second flight was made, again from Ojima Airfield, on 25 August, 1918, this time piloted by Army Cavalry Capt Naranosuke Oka, and three flights, each of several minutes, were made that day. Upon landing the third time, however, a wingtip touched the bank of the river-bed and the aeroplane was damaged once again.
This time, repairs took about a week. In making the repairs some changes were made in the design, as recommended by Capt Oka. This also called for a change in designation to Type 1-3. To avoid repeating the mishap because of the narrow take-off strip at Ojima, further flights were transferred to the Army's test base at Kagamigahara Airfield, north of Nagoya, a considerable distance away. On 13 September the aeroplane flew again, piloted by Capt Oka. After approximately 17 minutes in the air, the Nakajima Type 1-3 made a safe landing. However, while taxi-ing to the starting point, one of the wheels skidded into a ditch near the corner of the flying field, and yet again the airframe was damaged. The aeroplane was returned to the factory.
Again repairs, including more modifications suggested by Capt Oka, were made, making it necessary to change the designation to Type 1-4. For the next test flights, the long trip back to Kagamigahara was avoided by using the nearby Ojima Airfield. Becoming airborne on 9 November, once again at the hands of Nakajima's pilot Yozo Sato, structural failure occurred and the aeroplane crashed into the rushing waters of the river, destroying the aeroplane and severely injuring Sato.
It was later learned that centre of gravity problems plagued the aircraft from the very beginning, it being tail-heavy. Coupled with this, tractor-type aircraft were thought to be extremely difficult to control, since at that time most of the Army and Naval aircraft were pusher types. In truth, the failings of the Type 1 were due to inexperience on the part of those who designed it. Although built to serve Army needs, it was never delivered because of its total destruction. Thus came the unhappy ending to the first Nakajima aircraft.
Single-engine unequal-span biplane. Wooden structure with fabric covering. Crew of two in open cockpits.
125-130hp Hall-Scott A-5 six-cylinder water-cooled inline engine, driving a two-bladed wooden propeller.
Span 14m (45ft 11 1/2in); length 8m (26ft 3in); height 3m (9ft 10in); wing area 40sq m (430.57sq ft).
Empty weight 800kg (1,763lb); loaded weight 1,200kg (2,645Ib); wing loading 30kg/sq m(6.1Ib/sq ft); power loading 9.6kg/hp (21.llb/hp).
Maximum speed 65kt (75mph) at sea level; landing speed 32.5kt (37.5mph); service ceiling 3,000m (9,843 ft); endurance 4hr.
One built in July 1918.