Human Factors and The Dirty Dozen

The PEAR model analyzes human factors influencing safety and performance. 'People' focus on individuals' characteristics. 'Environment' considers the physical workplace. 'Actions' analyze the tasks and processes involved. 'Resources' encompass tangible and intangible assets necessary for task completion.

Lack of communication during a maintenance task can lead to errors, delays, and potential safety hazards.

Overconfidence due to repeated task performance can lead to complacency, increasing the risk of overlooking hazards or making mistakes.

Inadequate training, information, or skills can hinder a maintenance technician's ability to perform a task successfully, posing risks.

Anything that distracts a maintenance technician from the task at hand can cause errors or accidents. Distractions may come from external sources or internal thoughts.

The front of the airfoil, where the air first meets the wing.

The rear end of the airfoil, where the air leaves the wing.

An imaginary line connecting the leading and trailing edges of the airfoil.

The curvature of an airfoil's upper surface.

Distance measured from one wingtip to the other.

The area of the wing, calculated by multiplying its average length and width.

The shape of the wing as seen from above.

Ratio of wing span to wing chord.

Used on aircraft for landing on water surfaces. Replaces wheels with floats for water operations.

Aircraft landing gear designed for landing on snow or ice surfaces.

Landing gear that combines floats and retractable wheels, allowing aircraft to operate on both water and land.

Landing gear used on helicopters instead of wheels, providing stability for takeoff and landings on uneven terrain.

Rotation around the longitudinal axis of the aircraft, controlled by ailerons or spoilers.

Rotation around the lateral axis of the aircraft, controlled by elevators or a moving tailplane.

Rotation around the normal axis of the aircraft, controlled by the rudder.

The field of study focused on monitoring and controlling the movement of a craft from one location to another.

The act of transmitting information between entities using shared signs and symbols.

The process of observing and monitoring behavior or activities, often for control or management purposes.

An instrument that uses a canted internal gyro to show both the initial roll rate and stabilized rate of turn around the longitudinal (roll) axis. It displays how fast the aircraft is turning.

An instrument that uses a rotating gyro to display the current compass rose direction (heading) that the aircraft is flying.

An instrument that uses an internal pressure differential to visually indicate how fast the aircraft is climbing or descending.

A device that counts and displays the revolutions per minute (RPM) of the engine.

An instrument that measures the pressure of oil in the engine, indicating if the engine is getting enough lubrication.

An instrument that measures the temperature of the engine oil. It has a green area that indicates normal operating range, and a redline that signifies the maximum allowable oil temperature.

Indicates how the engine is performing by measuring air pressure.

Provides a clear picture of the engine's power output by displaying the airspeed.

A document providing detailed instructions for maintaining a specific aircraft component. It covers off-a/c maintenance tasks and helps return the component to a serviceable condition.

A collection of steps used to troubleshoot a problem in an aircraft system by replacing parts one at a time until the faulty one is found.

This document lists items in an aircraft that can be deferred without significantly affecting its safety. It's prepared by the aircraft manufacturer during certification.

A document prepared by an airline or operator, based on the MMEL, that specifies the minimum equipment required for their specific operations.

This document lists approved non-structural external parts that can be missing without affecting the aircraft's airworthiness.

This document includes information about modifications that can be incorporated into an aircraft. It informs owners and operators about safety, maintenance, or product improvement.

A mandatory notification to aircraft owners and operators about known safety deficiencies or hazards that need to be addressed on a specific model.

This document provides guidance and suggestions for demonstrating compliance with aviation regulations and standards.

A force that tends to stretch a structural member, like a tie.

A force that tends to shorten a structural member, like a strut.

A force that tends to slide one face of a material over its adjacent face, often seen in riveted joints.

Internal force per unit area inside a structural part due to external loads. Tensile loads create tensile stress, compressive loads create compressive stress.

The change in structural dimensions (deformation) caused by an external force.

A phenomenon that occurs in thin sheet materials when subjected to end loads or ties when subjected to compressive forces, resulting in the material bending or collapsing.

Forces that build up quickly, like those experienced during changes in flight conditions.

Constant forces that build up slowly, like those experienced by an aircraft on the ground.

The main structure or body of an aircraft.

A type of fuselage construction used for light, non-pressurized aircraft. It uses welded light gauge steel tubes covered with aluminum or fabric skin.

A type of fuselage construction used for light aircraft. All loads are carried by the skin with light internal frames to provide shape.

A fuselage construction where stressed skins are reinforced with structural members called stringers and longerons.

Beams in the fuselage that are fitted longitudinally from nose to tail, often placed below the floor to take the main bending loads.

Vertical structures in the fuselage that are open in the center, designed to take major loads and give the aircraft its shape.

Similar to frames but usually solid, designed to give the fuselage its shape and take some of the main loads.

Partitions separating the flight deck and cabin from the engine, protecting the crew and passengers in case of an engine fire.