BlackStar II MWD Tools

Flexible options for your MWD data acquisition needs


NOV’s BlackStar™ II MWD product line expands on the capabilities of the original BlackStar tools using lessons learned from more than a decade of drilling operations. The system has been reconceived to further enhance functionality and cost-effectiveness using advanced electronics that enable additional measurement capabilities and increased performance.

BlackStar II MWD tools are available in two configurations:

BlackStar II EM MWD tool

The BlackStar II electromagnetic (EM) measurement-while-drilling (MWD) tool sends information to the surface through the earth’s crust using low-frequency EM waves. Information is received at a surface antenna, decoded, and then processed by a computer and distributed to the driller’s readout display without the encumbrance of mud or wire transmission. Electromagnetic tools have no moving parts, enabling use in air-drilling conditions or high lost-circulation material environments where mud-pulse tools are rendered inoperable. In addition, surveys can be transmitted during connections, minimizing the nonproductive time associated with conventional mud-pulse tools.

BlackStar II dual-telemetry MWD tool

The BlackStar II dual-telemetry MWD tool combines the capabilities of both electromagnetic and mud-pulse data transmission to provide continuous drilling in the most challenging of conditions. The BlackStar II tool’s modular design allows flexibility in configuring the toolstring to maximize operational capabilities. Directional, drilling, and formation data are measured downhole and transmitted to surface as either EM waves or pressure pulses, where they are processed and displayed on the drilling console.


  • Downlinking options—EM and RPM
    • Provides flexibility
  • Diverse power management capabilities
    • Enables increased power output (up to 40 watts)
    • Offers the ability to shut down the transmitter while rotating
    • Enables modules to operate from a single 28-V battery stack
    • Provides dual-battery support 
  • User-configurable options
    • Offers multiple user-programmable frames: survey, steering, and rotation
    • Enables multiple open-circuit voltages in step increments
    • Enables additional measurement channels: axial, radial, and total vibration
  • Gamma and pressure modules
    • Integration of gamma (360° and DRG) module, with optional annular and internal pressure
  • On-board memory logging
    • Directional module—surveys stored in memory
    • Gamma module—gamma ray stored in memory
  • BlackStar II Dual Telemetry MWD Flyer

  • BlackStar II EM MWD Tool Flyer

  • Blackstar II EM MWD Tool Spec Sheet

  • Blackstar II Dual Telemetry MWD Tool Spec Sheet

Related Products

Tektonic Drill Bits

Achieve maximum drilling efficiency with the latest generation of polycrystalline diamond cutter (PDC) drill bit technology.

Learn more

BlackStar EM MWD Tool

Combining the latest in EM technology with the most durable and efficient design on the market.

Learn more