Spatial Services has used computer programs for the least squares adjustment of geodetic survey observations since 1961.

HAVOC (Horizontal Adjustment by Variation of Coordinates) was first compiled in 1972, and although developed primarily for in-house use, it has been widely distributed amongst the Australian survey industry. Some important features of this software are:

  • 2-dimensional adjustment only
  • all input / output data are text files
  • handles 8,000 observations and 1,000 stations
  • numerous observation types available
  • computes provisional and adjusted MGA coordinates
  • transforms ISG and AMG coordinates to MGA
  • provides full statistical analysis (error ellipses etc.)
  • computes rigorous scale factors and geodetic corrections automatically
  • applies geoid (AUSGeoid09) corrections where required

The current version 3.6 (11 November 2015) is available for download as an executable program (EXE 498.6 KB) only. To run in Windows, use a Command Prompt window or double click.

The documentation (PDF 440.2 KB) 3.6.10 (April 2014) is also required to assist with data formats and the use of the many options available.

Sample data files (ZIP 7.3 KB) are provided to illustrate the formats for various observation types.

Please note, that while all effort is made to ensure the accuracy and currency of this application, Spatial Services does not accept responsibility for any actions arising from its use.