E16A Zuiun
A E16A1 Yo-53 of the Yokosuka Kōkutai (Naval Air Group), as can be seen by its tail markings.
Role	Reconnaissance Floatplane Type of aircraft
Manufacturer	Aichi Kokuki
First flight	22 May 1942
Introduction	February 1944
Primary user	IJN Air Service
Produced	1944–1945
Number built	256[1]

The Aichi E16A Zuiun (瑞雲 "Auspicious Cloud", Allied reporting name "Paul") was a two-seat reconnaissance seaplane operated by the Imperial Japanese Navy during World War II.

Design and development

The Aichi E16A originated from a 1939 specification for a replacement for the Aichi E13A, which at that time had yet to be accepted by the Imperial Japanese Navy Air Service (IJNAS).^[2] Disagreements about the requirements in the 14-Shi specification prevented most manufacturers from submitting designs, but in 1941 a new 16-Shi specification was drafted by the IJNAS around the Aichi AM-22 design which had already been made by Aichi engineers Kishiro Matsuo and Yasuhiro Ozawa.^[2] The first AM-22, which first got the experimental designation Navy Experimental 16-Shi Reconnaissance Seaplane and later the short designation E16A1, was completed by May 1942 and was a conventional, low-wing monoplane equipped with two floats and had the unusual (for a seaplane) feature of being equipped with dive brakes, located in the front legs of the float struts, to allow it to operate in a secondary role as a dive bomber.

Variants

^[3][4]

E16A1 Experimental Type 16 reconnaissance seaplane (16試水上偵察機, 16-Shi Suijō Teisatsuki)

Initial named Experimental Type 14 two-seat reconnaissance seaplane (14試2座水上偵察機, 14-Shi 2-Za Suijō Teisatsuki). 3 prototypes produced. Mounted 1,300 hp (970 kW) Mitsubishi MK8A Kinsei 51 engine, 2 × forward-firing 7.7 mm (.303in) Type 97 machine guns, 1 × rearward-firing 7.7 mm Type 92 machine gun.

E16A1 Zuiun Model 11 (瑞雲11型, Zuiun 11-gata)

General production model. Mounted 1,300 hp (970 kW) Mitsubishi MK8N Kinsei 54 engine, 2 × forward-firing 20 mm Type 99-2 cannons, 1 × rearward-firing 13 mm Type 2 machine gun.

E16A2 Provisional name Zuiun Model 12 (仮称瑞雲12型, Kashō Zuiun 12-gata)

Initial named Zuiun Model 22. Single prototype with a 1,560 hp (1,160 kW) Mitsubishi MK8P Kinsei 62 radial engine. One plane converted from E16A1, incomplete.

Operators

 Japan^[1][3][4]

• Imperial Japanese Navy Air Service
• Naval vessel
  • Battleship Ise, supplied from 634th Kōkūtai.
  • Battleship Hyūga, supplied from 634th Kōkūtai.
• Air unit
  • Kitaura Kōkutai
  • Yokosuka Kōkutai
  • 634th Kōkutai
  • 801st Kōkutai
  • 301st Reconnaissance Hikōtai
  • 302nd Reconnaissance Hikōtai

Specifications (E16A1 Zuiun Model 11)

Data from Japanese Aircraft of the Pacific War^[1]

General characteristics

• Crew: 2
• Length: 10.833 m (35 ft 6 in)
• Wingspan: 12.81 m (42 ft 0 in)
• Height: 4.791 m (15 ft 9 in)
• Wing area: 28 m² (300 sq ft)
• Empty weight: 2,945 kg (6,493 lb)
• Gross weight: 3,900 kg (8,598 lb)
• Max takeoff weight: 4,553 kg (10,038 lb)
• Powerplant: 1 × Mitsubishi MK8D Kinsei 54 14-cylinder air-cooled radial piston engine, 970 kW (1,300 hp) for take-off

895 kW (1,200 hp) at 3,000 m (9,800 ft)

820 kW (1,100 hp) at 6,200 m (20,300 ft)

• Propellers: 3-bladed constant-speed propeller

Performance

• Maximum speed: 439 km/h (273 mph, 237 kn) at 5,500 m (18,000 ft)
• Cruise speed: 333 km/h (207 mph, 180 kn) at 5,000 m (16,000 ft)
• Range: 1,176 km (731 mi, 635 nmi)
• Ferry range: 2,420 km (1,500 mi, 1,310 nmi)
• Service ceiling: 10,000 m (33,000 ft)
• Rate of climb: 10 m/s (2,000 ft/min)
• Time to altitude: 3,000 m (9,800 ft) in 4 minutes 40 seconds
• Wing loading: 139.3 kg/m² (28.5 lb/sq ft)
• Power/mass: 0.25 kW/kg (0.15 hp/lb)

Armament

• Guns:
  
  • 2 fixed forward-firing 20 mm (0.787 in) Type 99 Mark 2 machine guns in the wings
  • 1 flexible rearward-firing 13 mm (0.512 in) Type 2 machine gun for the observer
• Bombs:
  
  • 250 kg (551 lb) of bombs