Nakajima-Fokker Ambulance Aircraft

The Japanese army first became interested in the potential of ambulance aircraft during the Manchurian incident of 1931, resulting in the modification of a Kawasaki-built Dornier Merkur passenger aircraft. Its publicly-funded success led to two similar conversions of Nakajima-built Fokker Super Universals, the first in 1932 and the second six years later, again publicly-funded. The cabins, which normally held six passengers, were redesigned by Army Dr Yoshinobu Teraj, a longterm advocate of ambulance aircraft. They could accommodate two stretcher and two seated patients plus a medical attendant or surgeon. Oxygen and intravenous feeding supplies were provided.[1]

Apart from the new cabin the Nakajima built Fokker Super Universals had the same design, structure and dimensions as the U.S.-built originals but differed in their engines, weights and performances. The US version had a 410 hp (310 kW) Pratt & Whitney Wasp[2] but the Nakajima Super Universal replaced this with a 420 hp (310 kW) Nakajima Jupiter early in production, then later a 460 hp (340 kW) Nakajima Kotobuki 2-kai-1. Similarly, the first ambulance had a Jupiter and the second a Kotobuki. Its greater power increased the second aircraft's cruising speed by 27% but its fuel consumption decreased the range by 14%.[1]

The individual histories of these two individual ambulance aircraft are not known but air ambulances played a vital role following the Manchurian Incident, when the first was available.[1] The Second Sino-Japanese War broke out in 1937, shortly before the donation of the second.

Data from Japanese Aircraft 1910-1941[1]

General characteristics

• Crew: two plus one medical attendant in cabin
• Capacity: two stretcher patients and two seated
• Length: 11.09 m (36 ft 5 in)
• Wingspan: 15.43 m (50 ft 7 in)
• Height: 2.82 m (9 ft 3 in)
• Wing area: 34.37 m² (370.0 sq ft)
• Empty weight: 1,720 kg (3,792 lb)
• Gross weight: 2,700 kg (5,952 lb)
• Powerplant: 1 × Nakajima Kotobuki 2-kai-1 nine cylinder radial, 340 kW (460 hp)
• Propellers: 2-bladed metal, fixed pitch

Performance

• Maximum speed: 248 km/h (154 mph, 134 kn)
• Cruise speed: 217 km/h (135 mph, 117 kn)
• Range: 1,000 km (560 mi, 490 nmi)
• Service ceiling: 6,000 m (20,000 ft)
• Time to altitude: 7 min 18 s to 1,000 m (3,300 ft)