We all know that the Mavis was mass-produced so no thought as to if was at least squadron size.
The Kawanishi H6K 'Mavis' was a long range flying boat that demonstrated that Kawanishi could complete with the best in the world, and that despite its lack of protection remained in front line service throughout the Second World War.
The H6K was designed as a result of a 8-Shi specification for a large flying boat issued by the Japanese navy in 1933. Kawanishi proposed two designs in response to this aircraft, the Type Q and Type R. Neither satisfied the Navy, and in 1934 a modified 9-Shi specification was issued. The new aircraft was to have a range of 2,500 nautical miles and a cruising speed of 120 knots.
Engine: Four Mitsubishi Kinsei 43 or 46
Power (Kinsei 43): 1,000hp at sea level, 990hp at 9,185ft
Power (Kinsei 46): 930hp at sea level, 1,070hp at 13,780ft
Crew: 9
Wing span: 131ft 2 23/32in
Length: 84ft 0 27/32in
Height: 20ft 6 27.32
Empty Weight: 25,810lb
Loaded Weight: 37,479lb
Max Speed: 211mph at 13,125ft
Cruising Speed: 138mph at 13,125ft
Service Ceiling: 31,530ft
Range: 2,981 miles
Armament: One 20mm cannon in tail, 7.7mm machine guns in bow, dorsal and two beam positions
Bomb-load: Two 1,764lb torpedoes or 2,205lb of bombs
http://www.wwiivehicles.com/japan/aircraft/flying-boat/kawanishi-h6k-mavis.asp (not the link above)
Crew: 9
Length: 25.63 m (84 ft 3 in)
Wingspan: 40.00 m (131 ft 2 in)
Height: 6.27 m (20 ft 6 in)
Empty weight: 11,707 kg (25,755 lb)
Loaded weight: 17,000 kg (37,400 lb)
Max. takeoff weight: 21,500 kg (47,300 lb)
Powerplant: 4 × Mitsubishi Kinsei 43 or 46 14-cylinder, air-cooled, radial engines, 746 kW (1,000 hp) each
Performance
Maximum speed: 331 km/h (211 mph)
Cruise speed: 138 mph
Range: 6,580 km (4,112 mi)
Service ceiling: 9,610 m (31,520 ft)
Rate of climb: 370 m/min (1,213 ft/min)
Wing loading: 100 kg/m<sup2 (20 lb/ft<sup2)
Power/mass: 0.17 kW/kg (0.11 hp/lb)
Armament
1× 7.7 mm (0.30 in) Type 97 machine gun in nose
1× Type 97 machine gun in spine
2× Type 97 machine guns in waist blisters
1× 20 mm Type 99 cannon in tail turret
2× 800 kg (1,764 lb) torpedoes or 1,000 kg (2,205 lb) of bombs