Part 1 – Human Factors in Unmanned Operations


To gain an understanding of the impacts of human factors, the relation of these to unmanned operations, and the associated safety precautions.


At the end of this briefing you will be able to:

  • Define the terms threat, error, undesired aircraft state and countermeasure.
  • Identify potential threats and errors applicable to UAV operations and propose appropriate countermeasures.
  • State personal safety precautions to be taken when engaged in UAV operations.

Threats & Errors

What is a Human Factor?

What: Application of scientific knowledge (mostly from the human sciences of psychology, anthropology, physiology and medicine) to the design, construction, operation, management and maintenance of products and systems.

Why: To reduce the likelihood of human error and therefore the likelihood of negative outcomes while operating or using products or systems.

How Accidents Occur

Defenses in depth model (source: Reason, 1997)

Key points to note:

  • Multiple defenses / layers of failure:
    • Orgsanisational.
    • Supervisory.
    • Personnel and operating environment.
    • Rules and procedures.
  • Downward gradient:
    • Each layer is sequential – failures at the top compromise defenses below.
    • The pilot (you) could be the last line of defense.

Threat & Error Management


  • Occurs outside the influence of the crew.
  • Increases operational complexity of a flight.
  • Requires crew attention and management to maintain safety margins.
  • Example: change of wind direction likely during duration of mission.


  • Crew action or inaction that leads to a deviation from crew or organisational intentions or expectations.
  • Reduces safety margins.
  • Increases probability of adverse operational events.
  • Example: operating crew does not check wind direction before setting the landing rally.

Undesired Aircraft State:

  • Position, speed, altitude or configuration of an aircraft that results from crew error.
  • Clearly reduces safety margins.
  • Example: UAV approaches with a tailwind, overshoots and crashes into a fence.

Refer to reference material (Defensive Flying for Pilots: An Introduction to Threat and Error Management) for full document. Accessed 18 Sep 2013:


Conflict / breakdown of separation between UAV and transiting traffic– Lookout – multi-pilot crew
– Listen out
– Communicate
Personnel other than those of the operator coming within 30 m– Lookout – multi-pilot crew
– Physical barriers
Airframe / component failure-Design & Testing Program
– Maintenance program
– Pre-flight checks
– Post flight checks
UAV launched with insufficient battery voltage– Pre-flight checklist includes battery voltage test
Pilot functioning adversely affected by fatigue, hunger or dehydration– Appropriate rest before mission
– Suitable area to take breaks
– Bring sufficient food and water for extended deployment
Pilot functioning adversely affected by alcohol or drugs– Minimum 8 hours between alcohol consumption and flying
– Sufficient time between consumption and flying to be free of effects of alcohol / drugs
– Check medications with DAME
Example breakdown of threats and potential countermeasures.

Human Operators

Situational Awareness

  • Perception of the current environment
  • Interpretation of the immediate situation
  • Anticipation of what will happen next


Use all available senses (sight, hearing, smell, feel etc):

  • Direct observation of vehicle
  • Direct observation of terrain
  • Direct observation of airspace / traffic (lookout)
  • GCS data
  • Radio
  • NOTAMs / weather


Converting perception into reality!

Perception illusion #1 (source: accessed 19 Sep 2013)
Perception illusion #2 (source: accessed 19 Sep 2013)
Perception illusion #3 (source: accessed 19 Sep 2013)

Hazardous Attitudes

AttitudeBehavioural Marker
Anti-AuthorityRefusal to listen to advice Contempt for the rules
DeferenceWhatever goes wrong is someone else’s fault Defers to opinion of others above using own initiative
ImpulsivenessCommits to action without considering consequences Acting on the spur of the moment
Invulnerability‘It will never happen to me’ syndrome
Macho‘There’s nothing I can’t do and there’s nothing I won’t try’
ResignationUnwillingness to take control of a situation Giving up


Cross-section of a human eye (source: accessed 19 Sep 2013)
  • Light enters through pupil.
  • Ciliary muscles shape the lens.
  • Image (upside-down) projected onto retina (part of the brain connected by the optic nerve) to interpretation.

Refractive Errors

Common types of vision issues:

  • Hyperopia (farsightedness)
    • Distant objects clear
    • Near objects blurry
    • Convex lens to correct
  • Myopia (nearsightedness)
    • Distant objects blurry
    • Near objects clear
    • Concave lens to correct
  • Astigmatism
    • Distortion of the image
    • Different parts unequally focused
    • Cylindrical lens to correct

Blind Spot

A “blind spot” occurs when image focused on the retina falls across the optic nerve.

Humans always have a blind spot, but our brains learn to ignore it. This can be very dangerous if we’re not aware!


  • Draw circle with cross in it on left side of paper.
  • Draw square on right side of paper.
  • Cover left eye.
  • Hold paper at arm’s length.
  • With right eye, look at the circle.
  • Move the paper closer to you while focusing on circle.
  • Square will disappear when image falls on optic nerve.

Safety during Outdoor Operations

The sun.
  • Don’t look directly at the sun
  • Personal Protective Equipment (PPE):
    • Hat
    • Sunglasses
    • Sunscreen
    • Long-sleeved shirt

Real-World Operations

Crew Coordination

 Basic principles of crew coordination:

  • Verbal and non-verbal communication factors
  • Barriers to communication
  • Listening skills
  • Assertion skills
  • Factors affecting decision-making processes
  • Communication:
    • Attitude
    • Personality
    • Judgement
    • Leadership style
  • Leadership
  • Qualities
  • Poor crew coordination
  • Other human factors

Effective Communication Techniques

Effects of stress on personal performance, ways of managing, and controlling stressors:

  • Concepts of fatigue
  • Environmental stress symptoms, causes and effects
  • Ergonomics of control systems and instruments
  • Principles of stress management
  • Short- and long-term stressor effects on performance
  • Stress and arousal interaction

Operational Considerations

  • Error management, including:
    • Error types.
    • Causes.
    • Consequences.
  • Human factors that may influence personal performance during RPAS operations.
  • Human performance and limitations, including:
    • The senses
    • Memory
    • Situational Awareness
  • In a “defense context“:
    • Relevant defense orders.
    • Commanded instructions.
  • Relevant Work Health & Safety (WHS), Occupational Health & Safety (OHS), and other procedures and regulations.

Regulations & Orders

Relevant Sections of Civil Aviation Safety Regulations (CASRs) and Civil Aviation Orders:

  • Human factors limitations.
  • Physical examination requirements.
  • Medical clearances.

Requirements for reporting and documenting safety incidents and safety critical errors that may have occurred during an RPAS Mission:

  • RPAS flight instruments visual scanning techniques
  • Undesired RPAS states:
    • Incorrect RPAS configuration associated with a reduced margin of safety.
    • Inappropriate RPAS flight mode awareness and selection.
    • Misapplication of flight controls.
    • RPAS pilot induced aircraft position.
    • RPAS pilot induced speed deviation.