Airborne Gravity

Introduction - System Development & Operations - Data Processing - Resolution and Accuracy - Conclusion

The Fugro airborne gravity system was developed, and continues to evolve, in accordance with five unique design criteria:

Develop a reliable and aircraft independent gravity system.
Measure geodetic quality GPS velocities, rather than using less accurate velocities computed from GPS positions.
Use exhaustive gravity sensor and platform modeling along with rigorous processing corrections in order to minimize filtering – "model, measure and correct – don’t over filter".
Provide clients with open access to all aspects of their data including in-field and final data processing and QC methods.
Evaluate the system resolution and accuracy using three independent analysis methods on data acquired in real world exploration conditions.

Aircraft independence required that the gravity system not be dependent on the flight characteristics of any specific aircraft, nor that the aircraft required any extensive aircraft airframe or system modifications. The Fugro system has been installed on six different aircraft all of which have been used to fly successful gravity airborne gravity surveys:

Cessna 208
Cessna 404
Cessna 421
Rockwell Aero-Commander 500 Shrike
Piper Aztec
Airship Industries R-300 airship (blimp)

This aircraft versatility and ease of gravity system installation, typically requiring less than one day, simplify mob/demob operations and reduce survey costs. Measuring geodetic quality GPS velocities required the use of state-of-the-art dual frequency GPS receivers and the development of customized post-mission GPS processing software. The Fugro system tracks aircraft kinematics with extreme accuracy, thus reducing the demands for extreme flight stability. The motto of the Fugro gravity system is "model, measure and correct - don’t over filter". Filtering is minimized by applying an extensive suite of corrections derived from GPS velocities, sensor and platform modeling measurements prior to filtering. Clients are provided open access to all aspects of their data including in-field and final data processing and QC methods. System resolution and accuracy is evaluated by three independently measured analysis methods on data acquired in real world exploration conditions.

Airborne Gravity Services are offered by Fugro-LCT in conjunction with Fugro Airborne Surveys.