Calculators

Online Calculators

• Dip of Sea Short of the Horizon
• Local Apparent Sideral Time
• UTC Time Tick
• Mercator Sailing
• Great Circle Sailing
• Conversion for Meters, Feet and Fathoms
• Speed for Measured Mile and Speed, Time, and Distance
• Length of a Degree of Latitude and Longitude
• Geographic Range
• Distance of the Horizon
• Magnetic Delcination
• True Wind Calculator

Phenomenon Calculators

• Twilight Calculator
• Rise, Set and Twilight of Sun and Moon
• Time Zone Map
• Night and Day View of the Earth

Resources

Electronic Bowditch Tables

• Pub 229
• Altitude Correction for Atmospheric Pressure
• Altitude Factors & Change of Altitude
• Compass Error from Amplitudes Observed on the Celestial Horizon
• Latitude and Longitude Factors
• Meridian Angle and Altitude of a Body on the Prime Vertical Circle
• Compass Error from Amplitudes Observed on the Visible Horizon
• Altitude Correction for Air Temperature
• Table of Offsets
• Meridional Parts
• Traverse Table

Paper Charts

• Print on demand NOAA charts
• Chart Updates

Esoteric

• Distance by Vertical Angle Measured Between Sea Horizon and Top of Object Beyond Sea Horizon
• Distance of an Object by Two Bearings
• Distance by Vertical Angle Measured Between Waterline at Object and Top of Object