Data Fliers


Fliers are anomalous soundings that misrepresent depths. Their detection is based on the threshold depth values that consider average depth recordings from adjacent data. In QAX, values that exceed the threshold are flagged as suspicious and require the operator to inspect their legitimacy.  



  1. Use QAX QA/QC tool to scan for fliers. Apply appropriate threshold values of the Laplacian and Gaussian operators that determine anomaly locations (see QAX SOP). In QAX, these are output as a series of raster files that can be imported to any geospatial applications project for overlay and confirmation.

  Pass Requirements  

  1. Fliers identified in the QAX scan have been identified and cleaned.  

  2. A scan of the data using QAX parameters as advised/calibrated by the operator results in a ‘Pass’ for flier identification. 




Test results   

Figure 1. QAX result for fliers check has passed. Flier check for dataset is cleared. 




This dataset is free of fliers. 


© Commonwealth of Australia (Geoscience Australia) year of publication.

With the exception of the Commonwealth Coat of Arms and where otherwise noted, this product is provided under a Creative Commons Attribution 4.0 International Licence.