I'm thinking of it with a hull form more like the Dornier Do-216 (though without the side bulges, and using larger stabilizing floats), not the huge sides like the historical Coronado. Given the height of the somewhat larger Do-216 at 26 feet with tail, and a somewhat oval shape (taller than it is broad), a diameter of 12 feet might be OK (15 feet high, 9 feet wide).
Aircraft Type or Name:
Consolidated PB2Y-1 Albatross
General Type:
Airplane = 1
Airship = 2
Orbiter = 3
1
Year of First Flight: 1939
Description
Flying Boat / Seaplane
Monoplane
Conventional Fuselage
A large seaplane patrol bomber, using the P&W RD-1650-32 diesel radial, the Pratt & Whitney produced version of the Junkers Jumo-208D. Armed with 7 0.50 machineguns (two each in dorsal, and tail turrets, with 1 each in nose and beam positions), and equipped with crew armor (+1500 lbs), self-sealing fuel tanks (+3500 lbs), and with radio-direction finding gear (+400 pounds). Can carry up to 10 500 pound bombs or depth bombs in cells in the inner wings.
Characteristics:
Weight (maximum) 72,000 lbs
Weight (empty) 41,241 lbs
Length 75 ft
Wingspan 140 ft
Wing Area 2,200 sq ft
Sweep 0 degrees
Engines 4
P&W RD-1650-32
Piston
1,521 hp
at 12,000 ft
Crew 10
Typical cost $0.149 million in 1939
Total number procured 2000
Performance:
Top Speed 227 kts = 261 mph
at 12,000 ft
Mach N/A
Operational Ceiling 28,000 ft
Range 3,200 nm = 3,685 miles
with 4,901 lbs payload
5,962 lbs released at halfway point
Climb 1,062 fpm
Cruise 180 kts = 207 mph
at 18,000 ft
Corner Speed 127 KIAS =
151 kts at 12,000 ft
Mach N/A
Turning Rate 15.0 deg/sec
Radius 1,953 ft
Internal Data:
Intake / Fan Diameter 10.75 ft
Bypass Ratio 100
Engine Weight 1875 lbs
Overall Efficiency 27 percent
Structural Factor 1.00
Number of Wings 1
Number of Fuselages 1
Limiting Airspeed 250 kts
Wing Ultimate g Load 3.00 g
Wing Taper 0.1
Wing Thickness at Root 3 ft
Tail / Canard Factor 0.4
Number of Nacelles 4
Length 6 ft
Diameter 4.5 ft
Fullness 0.5
Fuselage Diameter 12 ft
Fuselage Fullness 0.45
Pressurized Volume 0 percent
Cargo Decks 0
Cleanness 65 percent
Unstreamlined section 12.7 sq ft
User equipment 9,400 lbs