Aichi AB-6
# Aichi AB-6

The Aichi AB-6, or Aichi Experimental 7-Shi Reconnaissance Seaplane, was a prototype Japanese reconnaissance floatplane. It was a single-engined, three-seat biplane intended for the Imperial Japanese Navy, but only one was built, the rival aircraft from Kawanishi, the E7K being preferred.

## Design and development

In 1932, the Imperial Japanese Navy raised a specification for a long-range floatplane reconnaissance aircraft to replace its Yokosuka E1Y and E5Y operating from its seaplane tenders and battleships, requesting prototypes from Aichi and Kawanishi. Aichi's entry, the Aichi AB-6 or Aichi Experimental 7-Shi Reconnaissance Seaplane, designed by Tetsuo Miki, was based on the Heinkel He 62, one example of which had been imported by Aichi the previous year for evaluation against a similar requirement. The AB-6 was a biplane with folding wings for storage aboard ship, of all-metal construction with fabric covering, and powered by a single Hiro Type 91 W12 engine. Its crew of three, pilot, observer and radio operator/gunner were accommodated in an enclosed cockpit.

## Operational history

The prototype was completed in February 1933 and made its maiden flight from Nagoya harbor. While it had good handling in the air, its speed, take-off, and landing performance was disappointing, and the aircraft was modified to try to improve matters. It was fitted with revised wings, of different aerofoil section and with full-span leading edge slats. The original Hamilton-Standard two-bladed metal variable-pitch propeller was first replaced by a two-bladed wooden propeller and then a four-bladed wooden unit. Despite these changes, Kawanishi's design remained superior, and in 1934, was ordered into production as the Navy Type 94 Reconnaissance Seaplane, or Kawanishi E7K.

## Specifications (final configuration)

Data from Japanese Aircraft 1910–1941

General characteristics

* Crew: 3
* Length: 10.44 m (34 ft 3 in)
* Wingspan: 12.98 m (42 ft 7 in)
* Height: 4.80 m (15 ft 9 in)
* Wing area: 40.61 $m^2$ (437.1 sq ft)
* Empty weight: 1,920 kg (4,233 lb)
* Gross weight: 3,020 kg (6,658 lb)
* Max takeoff weight: 3,300 kg (7,275 lb)
* Powerplant: 1 × Hiro Type 91 water-cooled W12 engine, 470 kW (630 hp)

Performance

* Maximum speed: 230 km/h (140 mph, 120 kn) at sea level
* Cruise speed: 150 km/h (92 mph, 80 kn) at 1,000 m (3,300 ft)
* Stall speed: 81 km/h (50 mph, 44 kn)
* Endurance: 11.9 h
* Service ceiling: 4,850 m (15,910 ft)
* Time to altitude: 3,000 m (9,840 ft) in 14 min 54 s

Armament

* Guns: 1× fixed, forward firing 7.7 mm machine gun, 1 flexibly mounted in rear cockpit and 1× under fuselage
