NavPac 4: Free Software Upgrade for Users of NavPac 3.4

HM Nautical Almanac Office

January 10
12:29 2017

We are delighted to announce the release of the much anticipated NavPac 4, HMNAOs celestial navigation software package. This is available as a free optional upgrade for existing registered users of NavPac and Compact Data 2016-2020. NavPac 4 can be used alongside NavPac 3.4. However, continued support will be available for NavPac 3.4 until 2020. NavPac 4 provides a much improved user interface and several new tools and features designed to make celestial navigation easier for the navigator.

These include:

  • new star chart displays in the Find It function
  • a new feature called Find Next in the Sight Reduction function that calculates when and where a vessel will be for the next Sun rise/set/meridian passage and civil/nautical/astronomical twilight based on the vessels position, dead reckoning course and speed
  • a night mode which makes NavPac convenient to use in situations which require the user to retain their night vision

Further details can be found on HMNAOs NavPac web pages.

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