Navtools Lite is een programma voor astro-navigatie, vervaardigd door Stuurman/Programmeur Geert Sassen.
Het is bedoeld als backup voor bestaande GPS-navigatiesystemen.

Pure-Data heeft de registratie van het pakket op zich genomen. De laatste evaluatieversie is te downloaden. Een volledig overicht van de software en updates is te vinden op de site van Geert. Eventueel kunt u de evaluatie versie ook aanvragen op CD-ROM.

Functies van Navtools Lite

• Complete Nautical Almanac (61 stars, sun, moon, all planets)
• Starfinder: list of all visible stars at a certain time and location
• Times of rise, set, meridian passage for all celestial objects at a certain date and location
• Calculation of present true position after two or more sextant observations
• Calculation of compass error after azimuth bearing
• Continous calculation of the vessels dead-reckoning position
• Calculation of true course and speed after position update (either from sextant observations or GPS)
• Calculation of present current after each position update
• Waypoint-navigation, unlimited number of waypoints, either via greatcircle or rhumbline
• Continous calculation of required speed and required engine setting for a certain scheduled ETAVessels performance: calculation of average speed, engine revolutions, etc during all voyages - Calculation of average weather conditions during all voyages on a certain run and season.
• Calculation of vessels squat and true draft (based on present speed and conditions)
• Calculation of wheel over point distance (based on next course change and present speed)
• Calculation of geographical range of light or mountain top
• Calculation of distance to shore based on vertical sextant observation ('Hengeveld').
• Metric conversions: fathoms to meters, Celcius to Fahrenheit, etc, etc
• Hurricane tracking (continous calculation of hurricane position, distance, bearing, etc
• Logging (to standard text-file) of all user-actions (position updates, course/speed changes, etc