Gyrodata’s new GCAAT combines purpose built sensors, a new mechanization and advanced processing. Compared to IFR corrected MWD surveys GCAAT is 200% more precise.


GCAAT (Gyro Compassing All-Attitude Tool) combines purpose built sensors, a new mechanization and advanced processing enabling accurate surveying to horizontal and beyond. An additional benefit of the new mechanization is the virtual elimination of the notorious East/West no-go zone. Initially developed for use in the GWD90™ system, the instrument can now be deployed as a drop survey tool.

GCAAT graphFeatures

  • The tool can be dropped and pumped down to land in the BHA on any planned trip out of hole.
  • Survey data is recorded to memory at each connection.
  • BHA sag and Multi-station corrections are applied at the rig site.
  • Immediate comparison to previous surveys will detect possible gross errors.
  • Reduced uncertainty and increased safety factors as drilling progresses.
  • Closer approach to other wells is possible and better positioning in the reservoir results.
  • New mechanization eliminates East/West no-go zone.



  • Double the accuracy of IFR corrected MWD
  • Gross error detection
  • No degradation of accuracy in East/West directions
  • Each survey is independent resulting in no propagation of errors
  • Robust QC
  • Definitive survey generated as drilling progresses
  • Complete survey/re-survey of entire wellbore on each deployment
  • Little or no rig time used to record a highly accurate survey


Type Gyro Compassing All-Attitude Tool (GCAAT)
Environment 1.875" OD Probe: 150°C/300°F, 22K psi
Sensor performance ±0.05° Inclination, ±0.1° Azimuth, ±0.05° Tool face (1 sigma)
Inclination Range 0°-180°
Delay Setting 1-255 minutes
Survey station interval 15-30 seconds
Battery operating time 70 hours
Memory storage 30 hours of survey time
All specifications listed are for guideline purposes. Upon request, the tool performance can be obtained by applying the industry approved Gyrodata performance model to the wellbore profile.

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