Land XML US Foot

Problem:
Some applications that are set to use US survey Foot will honor the “foot” value in the LandXML. The application will convert the coordinates when reading the file from International Foot to US Survey Foot, which results in the coordinates having a different value as to the original coordinates. The application may or may not warn it is going to convert the coordinates.

This is not a wide spread issue because CAiCE, InRoads, SurvCE and Trimble currently does not convert the coordinates when reading LandXML files. Known applications that do honor the “Foot” value in LandXML file is Leica Office Geomatics and Land Desk Development.

One should always check coordinate values when importing data to verify the coordinates have not change.

Solution:
Edit LandXML file with text editor and modify the linearUnit="foot" to linearUnit="ussurveyfoot”. Be very careful not to change anything in the file except to modify the text “foot” to “ussurveyfoot”.

If you are working with external customers I would suggest always modifying the LandXML file and set the units to US Survey Foot. Currently InRoads XM allows you to set the linear units when you create the LandXML file. Make sure to always check the setting because it defaults to International Foot.