Strand 2: Safety, Tools, and Maintenance for Unmanned Aircraft Systems

Hazard

A condition that can cause harm, such as exposed propellers or swollen batteries.

Risk

The likelihood of harm occurring and the severity of that harm.

Safety Mindset

A disciplined way of thinking about risk to consistently prevent injuries and damage.

Risk-management loop

A process involving identification, assessment, mitigation, and reassessment of hazards.

Identifying hazards

The first step in the risk-management loop, determining what could cause harm.

Assessing risk

Evaluating how likely harm is and how severe it would be.

Mitigation

Actions taken to reduce the likelihood or severity of a hazard causing harm.

Reassess

Evaluating if mitigation measures effectively lowered the risk.

Situational Awareness

Understanding the environment and current conditions to prevent chain reactions of errors.

Normalization of Deviance

Accepting unsafe practices because they previously didn’t lead to negative outcomes.

Get-there-itis

The pressure to complete a mission that can lead to overlooking safety.

Confirmation Bias

The tendency to interpret evidence in a way that confirms pre-existing beliefs or assumptions.

Personal Protective Equipment (PPE)

Gear worn to minimize exposure to hazards leading to injury.

Rotating Machinery Hazards

Risks associated with spinning components, such as propellers.

Lithium Battery Hazards

Risks associated with using and handling lithium batteries.

Electrical and Thermal Hazards

Risks of burns and shorts due to high current and heat.

Workspace Setup

Organizing the work environment to reduce hazards and enhance safety.

Battery Basics

Understanding lithium-based packs and their configuration (cells in series).

Nominal Voltage

The standard operating voltage of a lithium polymer (LiPo) cell, approximately 3.7 V.

Watt-Hours (Wh)

A measure of energy calculated as $E = V \times Ah$.

Charging Safety

Ensuring safe practices while charging batteries to avoid overcharging and fires.

End-of-Life Indicators for Batteries

Signs like swelling, imbalance, and overheating that signal batteries should be replaced.

Torque Control

Applying the correct amount of force when tightening screws to avoid damage.

Vibration Control

Minimizing vibration that can affect sensor accuracy and overall aircraft performance.

Preflight Inspection

A safety check conducted before takeoff to identify critical failures.

Postflight Inspection

Reviewing the aircraft after flight to catch issues that developed during operation.

Scheduled Inspections

Regularly planned checks to manage wear and lifecycle of components.

Troubleshooting Method

Systematic approach of identifying and solving aircraft issues.

Mechanical Play in Motors

Movement of motor shafts that indicates wear or damage, leading to potential failures.

Calibration

Aligning sensor outputs with physical realities to ensure stable flight performance.

Firmware Update Safety

Steps taken to ensure safe and proper updates to the flight controller’s software.

Failsafe Testing

Verifying that the failsafe systems work correctly under controlled conditions.

Maintenance Logs

Records documenting inspections, maintenance actions, and component conditions.

Handling Damage

Damage to the aircraft that occurs during handling, potentially leading to failures later.

Environmental Exposure Hazards

Risks from dust, moisture, and temperature extremes impacting UAS performance.

Tool Maintenance Importance

Ensuring tools are well-kept to prevent maintenance-induced failures.

Field Kit Organization

Keeping spares and tools organized to minimize risks of foreign object debris.

Handling Guidelines

Best practices to lift and transport UAS to avoid structural damage.

Transport Safety

Ensuring UAS is secured and components are protected during transport.

Chain of Events

The sequence of actions that can lead to an incident, often preventable by early interventions.

Small UAS Risks

Understanding the unique hazards associated with operating small unmanned aircraft.

Prop Inspection

Checking propellers for damage and proper installation before operation.

Electrical Tools Best Practices

Using proper tools to ensure reliable electrical connections.

Using Multimeters

Applying multimeters to test voltage, continuity, and diagnose issues.

Recognizing Defective Props

Identifying minor defects in propellers that could lead to major failures.

Safety in the Workshop

Maintaining a safe environment when conducting UAS maintenance and repairs.