What is CALIB on Boeing 737? (Calibrator)

If you have ever wondered about the intricacies of an aircraft, you may have come across the term “calibrator” during your research. On a Boeing 737, the calibrator, also known by its abbreviation CALIB, plays a crucial role in ensuring the accuracy and reliability of various systems onboard. In this article, we will delve deeper into what a calibrator is, its functions, and its significance in the operation of a Boeing 737 aircraft.

The Role of the Calibrator

The calibrator on a Boeing 737 is a specialized device that is responsible for measuring, testing, and adjusting various electrical and mechanical systems. It acts as a reference tool to validate the readings and performance of different instruments and systems present on the aircraft. By ensuring precise and accurate measurements, the calibrator plays a vital role in ensuring the safety and efficiency of the aircraft.

One of the key functions of the calibrator is to measure and calibrate the aircraft’s temperature, pressure, and fuel quantity sensors. These sensors are critical for providing accurate data to the flight instruments, autopilot system, and other onboard systems. By regularly calibrating these sensors, the calibrator ensures that the readings displayed to the pilots and other systems are reliable, enabling them to make informed decisions during flight.

Additionally, the calibrator is responsible for testing and adjusting various electronic and electrical components, including voltage regulators, amplifiers, and transducers. By verifying the performance of these components, the calibrator helps maintain the overall integrity of the aircraft’s electrical system. It ensures that the electrical signals transmitted and received by the aircraft’s systems and instruments are accurate and within the desired parameters.

The calibrator also plays a crucial role in calibrating the aircraft’s flight instruments, such as altimeters, airspeed indicators, and attitude indicators. These instruments provide critical information to the pilots, allowing them to navigate and control the aircraft safely and efficiently. Regular calibration of these instruments ensures that the displayed readings are precise, enabling the pilots to make accurate judgments and respond to any changes or anomalies effectively.

Overall, the calibrator acts as a vital tool in ensuring the accuracy, reliability, and safety of the systems and instruments onboard a Boeing 737 aircraft.

Calibrator Maintenance and Calibration Process

Maintaining and calibrating the calibrator itself is crucial to ensure its accuracy and effectiveness. Boeing follows strict maintenance and calibration procedures to ensure the calibrator is in optimal condition for use.

The typical maintenance schedule for the calibrator involves regular inspections, cleaning, and functional tests. During inspections, technicians examine the calibrator for any physical damage, signs of wear, or malfunctions. Cleaning is performed to remove any dirt, dust, or contaminants that may affect the calibrator’s functionality. Functional tests ensure that the calibrator meets the required specifications and performs accurately.

In terms of calibration, the calibrator itself needs to be calibrated periodically to ensure its measurements are accurate. This calibration process involves comparing the readings of the calibrator against known standards or reference devices with higher accuracy. Any deviations or discrepancies are then adjusted and corrected to align the calibrator’s measurements with the reference standards. This ensures that the calibrator provides reliable measurements when used for testing and adjusting the aircraft’s systems and instruments.

The calibration process for the calibrator also includes verifying its performance across various operating ranges and environmental conditions. This ensures that the calibrator maintains its accuracy and reliability under different scenarios encountered during flight operations.

The Importance of Calibrator in Aviation Maintenance

The calibrator plays a crucial role in aviation maintenance, especially during scheduled inspections and troubleshooting. By using the calibrator, technicians can assess the performance and accuracy of various sensors, instruments, and systems onboard the Boeing 737.

The calibrator enables technicians to measure parameters such as temperature, pressure, fuel quantity, voltage, and current. By comparing these measurements against specified limits and known standards, technicians can identify any deviations or anomalies that may indicate a system failure or malfunction. This allows for timely maintenance and repairs, preventing potential issues from escalating and compromising the aircraft’s safety and performance.

Furthermore, the calibrator facilitates troubleshooting activities by providing accurate reference measurements. When a system or instrument is suspected to be faulty, technicians can use the calibrator to simulate specific inputs and compare the outputs with the expected values. This helps pinpoint the root cause of the problem and expedite the troubleshooting process, minimizing aircraft downtime.

Overall, the calibrator is an essential tool in aviation maintenance, enabling technicians to ensure the accuracy, reliability, and functionality of the various components and systems on a Boeing 737 aircraft.


The calibrator, or CALIB, plays a crucial role in the operation and maintenance of a Boeing 737 aircraft. It is responsible for measuring, testing, and adjusting various sensors, instruments, and systems onboard. By ensuring precise and accurate measurements, the calibrator contributes to the safety, efficiency, and reliability of the aircraft. Regular maintenance and calibration of the calibrator itself are essential to maintain its accuracy and effectiveness. In aviation maintenance, the calibrator enables technicians to assess and troubleshoot various components and systems, ensuring the overall integrity of the aircraft. With its vital functions and significance in the aviation industry, the calibrator remains an integral part of the Boeing 737 aircraft.

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