Why is calibration important when selecting a torque wrench?

• A. To extend the wrench's lifetime
• B. To calibrate cutting oils
• C. To ensure the wrench applies the indicated torque accurately
• D. To set the wrench to maximum torque

Answer: (C)

Calibration is essential because a torque wrench must deliver the exact torque it indicates. Without calibration, drift from wear, temperature, or misuse can make the indicated value inaccurate, so you might tighten a fastener to more or less than the spec. In aviation, applying the correct torque is critical for joint integrity and leak prevention, so you can’t rely on a gauge that isn’t verified. Calibration uses a certified reference to compare the wrench’s readings to actual torque and adjust the wrench so the indicated torque matches the real value. This ensures consistent performance across the tool’s range and among different tools in the shop. Regular calibration (and after impacts or heavy use) is part of proper maintenance. It’s not about changing cutting oils, extending tool life, or simply setting the wrench to a maximum torque.