Chart Work

Using the GPX utility and the Chart Work family of programs is it possible to do on an electronic nautical chart the work you do in a traditional way.
The three programs are:

  1. Lines of position and Great Circle sailings (orthodromic).
  2. Piloting: Currents and coastal fix.
  3. Search & Rescue search patterns.
GPX output includes:

Coastal navigation LoP

  • Bearing
  • Range
  • Horizontal angle
Celestial navigation LoP
  • Marcq St. Hilaire Line of Position
  • Circle of Position
Radionavigation LoP
  • RDF bearing
Route
  • Great Circle
  • Composite
Piloting and coastal fix
  • Currents Drift and Set
  • Lasheras
  • Ciclonic method
  • Fix by simultaneous Distance and Bearing of same object. Geographic Range, D( waterline, top of object )
  • Fix by 2 simultaneous Horizontal Angles
SAR search patterns – Patrones de búsqueda SAR
  • Expanding Square
  • Sector Search
  • Parallel Search for one ship
Resources:

Chart Work - Lines of Position & GC sailing

 

Chart Work - Traditional paper chart work on an ECS.

Coastal navigation

the three types of lines of position used are:

  • Bearing
  • Range
  • Horizontal angle

 


Fix by three simultaneous bearings.

Fix by three simultaneous bearings. Detail.
 

Celestial navigation

Offshore navigators use celestial navigation,sextant observations, as a backup for the GPS. Use a sextant for taking the altitude of a celestial body and OpenCPN to plot the celestial circle of position instead the LoP -Line of Position-. Repeat this and take at least three sights. You easily can check if any danger is near your fix, and the uncertainty in your position.


Parameters of a circle of position in astronavigation.


Route using the three types of sailings

  • Rhumb Line. Direct with OpenCPN (And also using Plugin Route_pi).
  • Great Circle(Direct in OpenCPN using using Plugin Route_pi).
  • Composite(Direct in OpenCPN using using Plugin Route_pi).
The three types of sailing are also available in ChartWork

Composite Route.


Composite Route plot with OpenCPN.

Radionavigation

RDF or radiogoniometer provide a bearing. Its line of position may be plot using GPX input. Two options:

  • RDF onboard
  • RDF on station
 

Fix by two RDF bearings with OpenCPN.

Chart Work - Piloting

Using the OpenCPN GPX utility and the Chart Work - Piloting program is it possible to do on an electronic nautical chart the work you do in a traditional way.


Piloting and coastal fix

Advanced piloting techniques - Currents

  • Currents Drift and Set
  • Lasheras
  • Ciclonic method (820. Determining Track Made Good by Plotting Running Fixes. Bowditch-American Practical Navigator.)

Coastal navigation
 

  • Fix by simultaneous Distance and Bearing of same object. Distance by:
Geographic Range
D( waterline, top of object ) 
  • Fix by 2 simultaneous Horizontal Angles

Chart Work - SAR search patterns

Search & Rescue utility that generates a GPX file for OpenCPN or Google Earth.



Search Pattern:
  • Expanding Square
  • Sector Search
  • Parallel Search for one ship
  • Parallel Search for two ships

Orientation as an input to takes into account tide, wind and drift.
Number of legs and its length may be configurable.



Free software to create the GPX file that serves as an input to OpenCPN is available at http://sites.google.com/site/navigationalalgorithms/ (Only for Windows®)