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minimizing the total time needed for monitoring GNSS base 
stations in comparison to area covered. 
From the standpoint of potential for reflights, the size of the 
project area relative to the mobilization distance was small. In 
the event of any need to re-fly, the aircraft was usually still at 
the same base when any need was determine, and any 
additional flight lines could be readily added before mobilizing 
to a new base. 
ACKNOWLEDGEMENTS 
The authors wish to acknowledge the support of staff members 
at both Leica Geosystems and Northwest Group in the 
production of this paper. In particular the authors thank Russell 
Carr at Northwest Group for the effort in relating the various 
challenges in the subject project from planning, acquisition and 
processing perspectives.