The design of a twin-float reconnaissance seaplane, to supersede the E13A1 in service, was initiated by Aichi in October 1940. This had the company designation AM-22, and in early 1941 the Imperial Japanese navy drew up a specification based upon this design. The first of three prototypes was flown for the first time during May 1942, but the resolution of stability problems, and of buffeting from the dive brakes occupied 15 months, the navy ordering the E16A1 into production in August 1943 as the Navy Reconnaissance Seaplane Zuiun Model 11.
Of low-wing monoplane configuration, the E16A1 had wings that incorporated trailing-edge flaps, and which could be folded for shipboard stowage. Basic structure was of metal, but the tailplane and wingtips were of wood, and all control surfaces were fabric covered. The single-step floats each included a controllable rudder to assist in on-water operation, and the forward mounting strut of the floats incorporated by hydraulically-actuated dive brakes to allow the E16A1 to operate as a dive-bomber. Accommodation for the crew of two was provided in tandem cockpits, enclosed by a long transparent canopy. Powerplant of the prototype and of early production Zuiun (auspicious cloud) aircraft consisted of a 1,300-hp (969-kW) Mitsubishi Kinsei 51 radial engine, driving a three-blade propeller. A single prototype of an improved E16A2 was being flight tested at the time of the Japanese surrender, powered by a 1,560-hp (1163-kW) Mitsubishi MK8P Kinsei 62 radial engine.
Production totalled 193 by Aichi and 59 by Nippon. Unfortunately for the navy, by the time the E16A1 entered service the Allies had gained air superiority and in consequence these aircraft, allocated the Allied codename 'Paul', suffered very heavy losses during 1944. The majority which survived were used for kamikaze operations in the Okinawa area.
Aichi E16A1 (late production)
Type: long-range reconnaissance floatplane
Powerplant: one 1,300-hp (969-kW) Mitsubishi MK8D Kinsei 54 14-cylinder radial piston engine
Performance: maximum speed at 18,045 ft (5500 m) 273 mph (440 km/h); cruising speed at 16,405 ft (5000 m) 208 mph (335 km/h); service ceiling 32,810 ft (10000 m); maximum range, 1,504 miles (2420 km)
Weights: empty 6,4931b (2945 kg); maximum take-off 10,038 lb (4553 kg)
Dimensions: span 42 ft 0 ¼ in (12.81 m); length 35 ft 6 ½ in (10.83 m); height 15 ft 8 ½ in (4.79 m); wing area 301.40 sq ft (28.00 m2)
Armament: two 20-mm wing-mounted Type 99 Model 2 cannon and one 13-mm (0.51-in) Type 2 machine-gun on flexible mount in aft position, plus one 551-lb (250-kg) bomb on under fuselage mounting
Operator: Japanese navy
Main production version.
Single prototype with Kinsei 62 piston engine.