What are the responsibilities of a directional driller assistant?

Directional Driller Assistant — Role Profile

Entry-to-intermediate field role supporting the Directional Driller in executing the well plan, monitoring drilling parameters, maintaining tools/telemetry, and ensuring trajectory control, data quality, and operational safety.

I. Core Responsibilities

• I.1 Trajectory execution support: Track inclination/azimuth, slide/rotate sequences, and build/hold/drop against plan and anti-collision rules; flag deviations.
• I.2 Real-time parameter monitoring: Watch WOB, RPM, ?P, flow, torque, ROP, ECD; recommend adjustments to maintain steering effectiveness and toolface control.
• I.3 Toolface and slide management: Set/hold toolface; manage slide sheets, slide yield, and micro-doglegs; document slide footage and outcomes.
• I.4 MWD/LWD data quality control: Validate gamma, inclinometry, azimuth, shock/vibe; trigger surveys at programmed intervals; perform survey QC and apply corrections per procedure.
• I.5 Survey computations and reporting: Calculate dogleg severity (DLS), closure distance, and TVD; maintain survey database, tally sheets, and daily DD reports for the wellsite.
• I.6 Pre-job preparation: Review well plan, BHA schematics, motor yields, RSS settings, jar placement, and expected build/turn rates; verify tool calibrations and offsets.
• I.7 BHA handling and rig-up oversight: Assist with bottomhole assembly makeup, motor bend verification, stabilizer placement checks, and surface system hook-up (sensors, WITS/WITSML).
• I.8 Operational communications: Log and relay trajectory status, slide instructions, and risk alerts to the driller, Directional Driller, and Company Representative.
• I.9 HSE conformance: Participate in toolbox talks, permit-to-work, dropped-object and pressure control protocols; enforce exclusion zones during rig-up/down.
• I.10 Troubleshooting support: Assist diagnosing loss of signal, pulser stalls, stick–slip, whirl, high shocks/vibrations, or motor stalls; recommend mitigation steps.
• I.11 Post-run close-out: Compile end-of-run summaries, lessons learned, BHA performance metrics (build rate, sliding efficiency, shock/vibe exposure), and handover packs.
• I.12 Inventory and logistics: Track downhole tool serials, batteries, subs, and spares; request resupply; ensure redress/inspection paperwork is current.

I.A Relevant formulas used on tour

• I.A.1 Dogleg Severity (DLS): $ \text{DLS}\ (\degree/100\ \text{ft}) = \dfrac{\arccos\!\left(\cos I_1 \cos I_2 + \sin I_1 \sin I_2 \cos \Delta A\right)}{\Delta MD}\times 100 \times \dfrac{180}{\pi} $ (angles in radians; use 30 m for metric).
• I.A.2 Minimum Curvature position update: $ RF = \dfrac{2}{\theta}\tan\left(\dfrac{\theta}{2}\right),\ \theta = \arccos\!\left(\cos I_1 \cos I_2 + \sin I_1 \sin I_2 \cos \Delta A\right) $; apply for $ \Delta N, \Delta E, \Delta TVD $ over $ \Delta MD $.
• I.A.3 Motor RPM (approx.): $ \text{Motor RPM} \approx \text{rev/gal} \times Q $; torque scales with $ \Delta P $ across the motor stages.
• I.A.4 Slide efficiency: $ \text{Slide eff.} = \dfrac{\text{Actual build (or turn)}}{\text{Expected build (or turn)}} \times 100\% $.

II. Required Skills and Physical Demands

• II.1 Technical skills:
  • Survey computation, anti-collision awareness, magnetic/gyro survey fundamentals.
  • Understanding of motor yields, RSS steering modes, and BHA dynamics (stability, bit walk, HFTO/LFTO).
  • Data acquisition and QC for MWD/LWD; telemetry (mud pulse/EM) fundamentals and troubleshooting.
  • Hydraulics basics (ECD, pressure drops), torque & drag concepts, slide/rotate optimization.
  • Field documentation: slide sheets, DD daily reports, end-of-section recaps.
• II.2 Soft skills:
  • Clear radio/comms, concise reporting, adherence to chain of command.
  • Situtational awareness, risk recognition, and stop-work authority usage.
  • Teamwork under rotation; calm, procedural approach during upsets.
  • Numeracy and attention to detail; disciplined record-keeping.
• II.3 Certifications (estimated):
  • Well control for drilling (Level 2–3) – assistant-level competency.
  • H2S, confined space, working at height, rig access, basic first aid.
  • Electrical/pressure safety awareness for downhole tools.
• II.4 Physical demands:
  • 12-hour tours; extended standing; ladder/stair climbing; handling tools/subs with proper lifting aids.
  • Exposure to noise, vibration, heat/cold, and hazardous atmospheres; PPE compliance.
  • Night-shift work; rapid response to alarms and operational changes.

III. Typical Tools/Software/Equipment Used

• III.1 Downhole systems: Mud motors (adjustable/fixed bent); rotary steerable systems; MWD inclino/azimuthal probes; pulser or EM transmitters; LWD gamma/resistivity/sonic/density where applicable.
• III.2 Surface sensors and acquisition: Hookload, SPP, flow-in/out, pit volume, RPM, torque, depth tracking; rig-floor encoders; surface decoding units; WITS/WITSML gateways.
• III.3 Software (estimated examples): Survey/anti-collision and well planning tools (e.g., COMPASS, WellPlan), hydraulics/torque & drag calculators, real-time WITSML viewers, spreadsheet templates, plotting utilities.
• III.4 Calibration and inspection: Inclinometer stands, magnetometers checks, gamma calibration pads, pressure test pumps, torque-turn monitors.
• III.5 Communications: Rig EDR, radio systems, satellite data links for real-time ops centers.

IV. Work Environment

• IV.1 Location: Land rigs, offshore jack-ups, platforms, or floaters; remote sites with limited amenities.
• IV.2 Shifts/rotation: 12-hour tours; common rotations 14–14, 21–21, or 28–28; nights often assigned to assistants.
• IV.3 Travel: Mobilization to/from rig; occasional base/shop days for tool prep and training.
• IV.4 Conditions: Weather exposure on land/offshore; motion on floaters; strict HSE and permit systems.

V. Reporting Lines and Cross-Functional Interfaces

• V.1 Reports to: Directional Driller (wellsite). Functional oversight by the Operator’s Wellsite Representative for program adherence.
• V.2 Direct interfaces:
  • Driller and Toolpusher: execution of slide/rotate, parameter changes, and connection procedures.
  • MWD/LWD Engineer: survey timing, telemetry health, battery/pulser management, and LWD QC.
  • Mud Engineer: rheology, density, and flow adjustments impacting telemetry/ECD and motor/RSS performance.
  • Wellsite Geologist/Geosteering: target updates, structural dips, and landing adjustments.
  • Service Specialists: motors, RSS, bits, jars; BHA inspection and redress coordination.
• V.3 Handoffs: Provides end-of-tour and end-of-run updates to the incoming DD team, EDR data annotations, survey databases, and daily trajectory summaries to the Operator’s team.

VI. Career Ladder

• VI.1 Next-step roles: Directional Driller; Senior MWD/LWD Engineer; RSS Specialist; Field Supervisor (directional services).
• VI.2 What’s needed to move up (estimated):
  • Demonstrated independent handling of surveys, slide planning, and real-time decisions under DD oversight across multiple hole sizes and lithologies.
  • Completion of company competency modules for trajectory control, anti-collision, and BHA design basics.
  • Well control certification (Level 3), advanced survey/anti-collision training, and documented performance KPIs (on-depth/on-azimuth, low NPT).
• VI.3 Typical timeframe (estimated): 18–36 months with 10–20 wells, including landings and curve sections, before stepping into full DD responsibilities.

VII. Deliverables & Interfaces

• VII.1 Key deliverables:
  • Accurate and validated survey sets with QC notes and corrections applied per policy.
  • Slide sheets with expected vs. actual build/turn, slide footage, and efficiency metrics.
  • Daily DD report: trajectory status, DLS trends, shocks/vibrations, parameter changes, and risk register updates.
  • End-of-run and end-of-section summaries with BHA performance statistics and lessons learned.
• VII.2 Upstream inputs: Approved well plan and anti-collision rules, BHA programs, motor/RSS settings, and geosteering targets.
• VII.3 Downstream handoffs: Operator’s subsurface/drilling team, real-time operations center, and next tour DD; data packages to MWD/LWD data processing for final well files.

VIII. Toolchain Snapshot

• VIII.1 Planning/QC: WellPlan, COMPASS (survey/anti-collision), torque & drag and hydraulics calculators, spreadsheet templates.
• VIII.2 Real-time: EDR/WITSML viewer, surface decoding systems, shock/vibe dashboards, parameter trend charts.
• VIII.3 Hardware: MWD/LWD toolstring, mud motor/RSS, jar/accelerator, stabilizers, subs, calibration fixtures, and pressure test equipment.

IX. Progression Trigger

Typically promoted after (estimated): 12–24 hitches or 10–20 wells completed with documented competency sign-offs, consistent survey/data quality, successful curve/landing assistance, plus current Level 3 well control and passing internal DD assessment.