How can I convert inches to UK nautical miles?
Divide by 72,960. A UK nautical mile – the old Admiralty mile – is exactly 6,080 feet, and 6,080 × 12 gives 72,960 inches.
So 1,000,000 inches comes to about 13.71 UK nautical miles. The numbers get long fast; if the inch figure has too many digits to handle, divide by 12 first to get feet, then by 6,080.
The international nautical mile is slightly shorter, at exactly 1,852 m, so check which one the chart means.
What is an inch?
An inch is a length unit normally used in the United States and, occasionally, in the United Kingdom. It is defined as a twelth (1/12th) of a foot. The inch is normally subdivided into fractions of an inch such as the ½, ¼ and ⅛.
An inch was originally the width of a man's thumb. It is still the everyday length unit in the United States, and TV and computer screens are sold by their size in inches worldwide.
Inches are used in combination with other units of imperial measurement such as feet and yards. For example, a standard door in the United States a football field is 100 yards long or 300 feet or 3,600 inches.
What is a UK Nautical Mile?
The UK nautical mile was based on one minute of latitude, ie 1/60th of a degree. The Earth is not a perfect sphere, so a minute of latitude varies slightly with latitude, which is why a fixed length had to be chosen.
The UK nautical mile, also called the Admiralty mile, was fixed at 6,080 feet, which is 1,853.184 meters. That is 1.184 meters longer than the international nautical mile of 1,852 meters (6,076.11549 feet), which the UK adopted in 1970.