Aviation maintenance professionals rely on force measurement equipment to complete work on aircraft. To make sure that these tools are performing as expected, force measurement calibration is required. This includes testing for equipment such as load cells, tensiometers, and dynamometers. Force measurement equipment testing uses processes that determine direction and magnitude.
The International System of Units (SI) is used for force measurement. SI was adopted to avoid conversion errors. When looking at a force measurement calibration test results, readings will be expressed in Newtons. One Newton is the unit of force required to accelerate a 1 kg mass a distance of 1 meter per second. The abbreviation is N. Force measurement calibration uses newton reading to ensure accurate readings.
Testing for Accuracy
When considering force measurement calibration, the technician is testing to ensure repeatability. Each measurement should have equivalent output given the same amount of applied force. The environment has an effect on output. Calibration technicians will mirror conditions as closely as possible during testing. Many types of force measurement equipment use dynamic force, which varies. Equipment can become fatigued, leading to a higher uncertainty rate. The fatigue life of equipment refers to the amount of times the specified force can be applied while meeting the uncertainty standard. Fatigued equipment can also be considered out of calibration.
Reliability & Calibration
To ensure that measurement instruments are still performing correctly, they must be checked periodically. Most force measurement equipment has a manufacturer recommended calibration interval. For example, most load cells have an annual calibration cycle. Force measurement calibration can be adjusted over time to reflect usage, equipment that is used more frequently can be calibrated on a shorter cycle.
If force measurement equipment is altered in any way or has sustained damage, the readings may become inaccurate. Depending on equipment sensitivity, it may not take much damage to significantly alter performance. To ensure reliability, these instruments should be set aside until they are checked for accuracy.