METROLOGY IN THE SERVICE OF AIR TRAFFIC SAFETY

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In aviation, there is no room for inaccuracies. Every instrument, sensor, and measuring tool must be calibrated with utmost care — because passenger safety and flight reliability depend on precise measurements.

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Aircraft are complex systems that rely on hundreds of different measurements. Altimeters, airspeed indicators, and pressure sensors provide pilots with data without which flight would be impossible. If measurements are inaccurate, even an error of just a few percent can mean the difference between a safe and a dangerous manoeuvre.

(Visual 1: Aircraft cockpit with measuring instruments / Source: Public domain)

 

Precise and accurate air-pressure measurement is essential for determining flight altitude. This is why aircraft pressure sensors are regularly calibrated against reference instruments, as even the smallest deviation can lead to misjudging the distance from the ground or nearby aircraft. Equally important is accurate measurement of tyre pressure — which means regular calibration of pressure gauges.

(Visual 2: Calibration of a pressure gauge in an ISO/IEC 17025 accredited calibration laboratory / Source: Metroteka d.o.o.)

 

Torque measurements used during aircraft maintenance are just as crucial. Torque wrenches are used to tighten bolts on engines and wings to an exact torque value. If a torque wrench is inaccurate and delivers too low a value, a bolt may remain insufficiently tightened and come loose during flight. If it delivers too high a value, a bolt may be overstressed and break.

(Visual 3: Wheel bolt tightening on a C-5M Super Galaxy aircraft at Dover Air Force Base, Delaware, United States / Photo: 1st Lt. Remoshay R. Nelson, 436th Airlift Wing Public Affairs, via DVIDS, Public Domain)

 

In practice, torque wrenches are used, for example, when tightening bolts that secure aircraft wheels. Every bolt must be tightened equally and precisely. Typical torque values range from 200 to 400 Nm, far higher than those used for car wheels. Even small deviations in this range can affect stability and safety during takeoff and landing. A calibrated torque wrench ensures that all bolts are tightened exactly according to technical specifications.

From the cockpit to the maintenance hangar, metrology is the invisible guardian of air travel safety.