Status of NavPac Software
The release dates of the different versions of the NavPac software, for both
are given below as well as any relevant patches and the status of support for
- 3.1.6 – Original release on CD in NavPac and Compact
- 3.1.7 – Not released
- 3.1.8 – Released for download: 15/06/2010
- 3.1.9 – Released for download: 06/12/2011
- 3.1.10 – Released for download: 04/03/2014
- 3.4.0 – Released on CD in NavPac and Compact Data
- 3.1.x – Support ended for NavPac 3.1 versions:
- 4.0.12 – Agreed release for download: 12/01/2017
- 4.1.1 – Release on CD with NavPac and Compact Data
- 3.4.0 – Support ended for NavPac 3.4.0: 01/01/2021
- 4.0.12 – Support ended for NavPac 4.0.12: 01/01/2021
- 4.1.2 – Release of patch to update
NavPac 4.1.1 to NavPac 4.1.2: 29/03/2021
- 4.2.0 – Agreed release for
- 4.1.x – Support ended for
NavPac 4.1.x with the release of 4.2.0: 22/04/2022
- With the release of an upgrade from
NavPac 4.1.x to 4.2.0, users should upgrade to 4.2.0 with immediate
- All versions of NavPac 3.1, 3.4, 4.0
and 4.1 are unsupported.
Log of Changes / Bug Fixes
This update makes the following changes:
Across the application:
- Resolved an issue where the screen would continually attempt to resize
itself at certain screen resolutions.
- Resolved an issue where the maximum temperature in Fahrenheit that could
be entered was 60 (new limit is 140).
- Resolved issues where NavPac issued incorrect error messages, went
unresponsive, or crashed due to Windows Regional Settings regarding separator
- Resolved star icon issues due to Windows Regional Settings.
- Resolved an issue where the map did not update displayed material when
in Mercator setting at high latitudes.
- Resolved a display issue in angle entry boxes where the decimal arcminute
resolved to 60.0 rather than corresponding whole degree.
- Resolved a display issue in course entry boxes where the bearing resolved
to 360.0 rather than 0.0.
- Improved Night Mode for entry boxes, list borders etc.
- Improved star magnitude labelling in the Key for star charts.
In Sight Reduction:
- Resolved an issue where the aesthetic position lines did not function as
expected when operating close to the 180th Meridian.
- Added the additional function to allow the user to change the Product Key
being used prior to Unlock.
In the background:
- Several issues regarding security and installation have been resolved.
- Several maintenance issues have been resolved or upgraded in order to keep NavPac 4
supportable. These include:
- Updated digital signatures on all executable files (.EXEs and .DLLs).
- All executable files (.EXEs and .DLLs) now target the .NET 4.8 Framework.
Before running the NavPacInstaller.exe file:
The NavPac installer for version 4.2 will uninstall a NavPac 4.1 installation if one is present
(does not include the desktop shortcut or user generated files).
It is recommended that any existing NavPac version number is checked before running the Installer
by clicking the “About” button from the “Home” screen. If it begins 4.2, there is no need to run the
NavPac Installer for 4.2.
Running the NavPacInstaller.exe file
If NavPac 4.1 was installed on the system previously, the installer will run without asking for a
Product Key or activation information.
If NavPac was not installed on the system previously, the installer will require a Product Key to
be entered and the normal activation process to be followed.
After running the NavPacInstaller.exe file
Run NavPac 4.2 and click the “About” button. Near the bottom of the “About” window you should see
that NavPac is now running as version 4.2.0.
Several changes were made to address issues reported with Navpac version
4.1.1. The patch made the following changes:
- Fixed a bug that caused NavPac to go unresponsive/crash when
transferring high latitude values into certain functions.
- Updated a constant used to calculate GHA Aries.
- Fixed a bug which prevented Time Zones being saved to and loaded
from preferences files.
- Fixed a bug which prevented buttons in the top right of the
screen being displayed when using additional functionality
- General improvements to file access.
A number of internal changes have been made to this version to improve
performance and support for future updates.
- Improvements have been made to the night mode, particularly
to some of the buttons.
NavPac 4.0 is a complete update of the NavPac software from previous
versions. The user interface has been completely redesigned and new tools
added. However, many of the features of earlier versions remain and will
be recognisable to existing users.
The following is a list of improvements and new features that have been
incorporated into NavPac 4.
- A 'Night Mode' has been added. Clicking the Day/Night View button
allows for switching between the standard colour scheme and one designed for
use at night or in twilight conditions.
- A Print Preview option has been added.
- Transferring values between functions now requires explicit
confirmation by the user. Transferring of values will only happen if, for
the majority of functions, the Transfer Values button is clicked. The Use
Values button must be clicked when Preferences is altered and there are a
number of buttons that can be used when using Sight Reduction.
- Preferences: A default pressure and temperature can now be
- Route Planner: The algorithm for calculating routes close to the
poles has been improved, allowing great circle routes to pass through the
- Find It: Two new star plot views have been included, Sweep and
- Route Planner and Sight Reduction: Plots showing results of
calculations along with coastal outlines have been added.
- Sight Reduction: The time of the fix can now be different to the
time of the base position.
- Sight Reduction: A function has been added to find the next
phenomena that occurs after the time of fix, based on the base position and
the legs entered into the log.
- Sight Reduction: The formula for calculating the position on a
leg when using the non-WGS84 option has been improved. It now differs from
that given in the book NavPac and Compact Data (NCD).
- An online-help-file is provided, which is displayed whenever the
keyboard's F1 key is pressed.
- Almanac, Find It and Sight Reduction: Magnitudes of the planets
have been included and are tabulated.
The following are a list of operating differences between previous versions
of NavPac and NavPac 4 resulting from the fully redesigned user interface.
- The NavPac functions are now accessed from a menu of icons
located at the top of all screens, unlike in NavPac 3 where a main screen
had to be returned to in order to access a different function.
- Each individual function is now contained on one screen, unlike
the multiple screens used in NavPac 3.
- Preferences: The Options screen found in NavPac 3 has been
- Preferences: The file extension for the saved options has changed
from .ini to .npp.
- Preferences: The default path for the ephemerides used can no
longer be altered.
- Rise and Set: Results are now shown all in one list, unlike in
NavPac 3 where, for multiple objects, only one day was shown at a time.
- Find It: The altitude and azimuth range can now be altered
continuously while the results are shown on screen. NavPac 4 also shows
objects outside the selected range, but above the horizon, on the plot,
although they cannot be selected.
- Find It: Function no longer automatically adds selected stars to
Sight Reduction, but they can instead be added by clicking the Add Selection
to Sight Reduction button.
- Find It: The added choice of plots in NavPac 4 means the user
must choose which to show by clicking the appropriate button. All plots now
have a key that can be displayed and the Ship's View plot has the option to
add constellation stars and lines, as well as a focus aid to help with
manipulation of the plot using the mouse.
- Find It: Some symbols have been altered for the plots.
- Find It: Function no longer has an option to save the objects
- Route Planner: The options to choose the parameters that will be
calculated have been simplified to one list, clearly stating the
- Route Planner: The input boxes that show calculated results,
rather than inputs, are made unavailable for user input. Therefore the
Calculate option that defines which parameters are inputs and which are
calculated should be chosen before entering user inputs.
- Route Planner: The waypoint to be transferred can now be chosen
directly from the route report. Whether the time zone is included in the
transfer can be selected before clicking the Transfer Values button.
- Sight Reduction: The log is now shown on the screen at all times,
and from it observations can be selected or deselected for use. Observations
can now be edited or deleted using the appropriate buttons and, when
editing, other user interactions are locked until editing has been
- Sight Reduction: The details of the observations and calculated
fix can be shown by expanding the Details results box.
- Sight Reduction: The plot of position lines has been altered from
a 20-nautical mile square in NavPac 3 to a zoomable plot with a choice of
projections in NavPac 4.
- Sight Reduction: The file extension for the saved values has
changed from .dat to .nps.