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Predict Turbine Failures from Sensor Data

EDFMediumMachine Learning00:00
EDF
Your interviewer · Research Scientist
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Interviewer

Welcome to your interview for the Research Scientist role at EDF.

The question is on your right: Predict Turbine Failures from Sensor Data. Take a moment with it first.

Talk your thinking through with me if you like - when you're confident, submit your answer and I'll grade it like a real screen. You have three graded attempts to score 7/10 or better.

Only Submit answer is graded - discussion is free practice.

Problem

Business Context

AeroGrid operates 1,200 industrial gas turbines across power plants in North America. Unplanned turbine downtime is expensive, so the reliability team wants a model that predicts whether a turbine will require a maintenance intervention within the next 7 days, using historical sensor and maintenance data.

Dataset

The training data is built at the turbine-day level from SCADA logs, alarm events, and maintenance records.

Feature GroupCountExamples
Sensor aggregates28avg_bearing_temp_1h, max_vibration_24h, exhaust_temp_std_6h, oil_pressure_min_12h
Operating context9ambient_temp, load_pct, startup_count_7d, runtime_hours_since_overhaul
Alarm/event features7alarm_count_24h, critical_alarm_flag, trip_events_30d
Asset metadata6turbine_model, site_id, fuel_type, turbine_age_years
Maintenance history5days_since_last_service, prior_failure_count_180d, replaced_component_type
  • Size: 410K turbine-days across 36 months, 55 features
  • Target: Binary label indicating whether a turbine has a failure or maintenance-triggering fault within the next 7 days
  • Class balance: Highly imbalanced, about 4.6% positive
  • Missing data: 12% missing in some sensor windows due to telemetry gaps; 6% missing in maintenance-history fields for newly onboarded turbines

Success Criteria

A production-ready model should achieve strong early-warning performance: PR-AUC above 0.45, recall above 75% at precision of at least 35%, and top-decile lift above 4x versus random ranking.

Constraints

  • Predictions run every hour in batch and must score all active turbines in under 5 minutes
  • Reliability engineers need interpretable drivers behind each alert
  • Data leakage from future maintenance actions or post-failure signals is not allowed
  • Model retraining should be feasible monthly on standard cloud CPU instances

Deliverables

  1. Build a binary classification pipeline to predict 7-day turbine failure risk.
  2. Explain feature engineering choices for time-windowed sensor data.
  3. Justify model selection and validation strategy for temporal data.
  4. Evaluate the model with metrics appropriate for rare-event prediction.
  5. Describe how you would set an alert threshold for maintenance operations.