Accuracy and Calibration Failures in Science and Engineering

4Calibration Drift in Action: Industry-Specific Failures

Abstract

Thermocouple drift in aerospace and power generation industries, notably impacting Type K and Type N sensors, led to undetected temperature deviations in jet engines and turbines during the 1980s-1990s. High-temperature oxidation and unstable metallurgy caused signal drift, undermining reliability. Corrective actions included mandatory recalibration schedules, adoption of AMS 2750 standards, and use of drift-resistant materials. Enhanced sensor design with protective sheaths and redundancy systems improved reliability. Lifecycle tracking and documentation of thermal exposure became essential, elevating calibration to a critical function for ensuring accurate temperature data in mission-critical applications. Several other case studies are explored.

Keywords: Thermocouple drift, pressure transducers, pH electrodes, CT scanner dosimetry, mass standards, gas chromatography (GC), optical emission spectrometry (OES)

There have been a few notable incidents across various industries where calibration standards changed or drifted without timely communication or detection, leading to significant consequences. These examples are often used in metrology and quality training to highlight the importance of traceability, communication, and oversight. Here are some documented cases:

Thermocouple Drift in Aerospace and Power Industries

Industry: Aerospace, Power Generation

• Timeframe: 1980s–1990s (still periodically an issue) ...