Scale = Model dimensions / Full scale dimensions
Using wingspan:
Scale = 65 inch / 37 feet = 65 inch / 444 inch = 1/6.8 = 1/7 approximately
Copied from
http://en.wikipedia.org/wiki/P-51_Mustang
P-51D Mustang
General characteristics
• Crew: 1
• Length: 32 ft 3 in (9.83 m)
• Wingspan: 37 ft 0 in (11.28 m)
• Height: 13 ft 8 in (4.17 m)
• Wing area: 235 ft² (21.83 m²)
• Empty weight: 7,635 lb (3,465 kg)
• Loaded weight: 9,200 lb (4,175 kg)
• Max takeoff weight: 12,100 lb (5,490 kg)