Human Performance & Limitations

The PPL lesson was about the individual pilot: hypoxia, vision, illusions and fitness to fly. As a commercial pilot you will usually work in a crew, on schedules that cross time zones and the night. This lesson is about working well with other people and managing fatigue, workload and automation.

1. Crew resource management (CRM)

CRM is using all the resources available – people, information and equipment – to fly safely. It grew out of accidents where a working aircraft was lost because the crew did not communicate or share the workload. Its main skills:

• Communication: clear, complete and checked – say what you mean, confirm you were understood.
• Leadership and teamwork: the captain leads, but every crew member speaks up.
• Situational awareness: knowing what is going on around you and what will happen next.
• Workload management: planning, sharing tasks and setting priorities.
• Decision making: gathering information, considering options, deciding and reviewing.

The flight-deck gradient

The authority gradient between captain and first officer should be neither too steep (the first officer is afraid to speak) nor too flat (no one takes charge). A junior pilot who sees a problem must speak up, using escalating steps if needed: state the concern, the problem, a proposed solution, and finally take action if safety demands it.

2. Situational awareness

Situational awareness has three levels: perceiving what is happening, understanding what it means, and predicting what will happen next. It is lost through distraction, fixation on one problem, high workload and complacency. Warning signs: confusion, nobody flying the aircraft, deviations from the plan that nobody explains, and the feeling that "something isn't right". When that happens, return to the basics: aviate, navigate, communicate.

3. Threat and error management (TEM)

Element	Examples	Response
Threats (outside the crew's control)	Weather, terrain, a late runway change, a technical fault, a difficult airport	Anticipate them in briefings
Errors (crew actions or omissions)	A wrong altitude set, a missed checklist item, a misheard clearance	Detect them with cross-checks and checklists
Undesired aircraft states	Wrong speed, unstable approach, wrong taxiway	Recover: go around, stop, correct

4. Briefings and standard operating procedures

Briefings turn individual plans into a shared one. A good departure or approach briefing is short and covers what is different today: the threats, the plan, and what each pilot will do if something goes wrong. SOPs make every crew work the same way, so two pilots who have never met can fly together smoothly.

5. Sleep, fatigue and the body clock

• The body runs on a circadian rhythm of about 24 hours. Alertness is lowest around 02:00–06:00 body time – the "window of circadian low" – with a smaller dip in the early afternoon.
• Adults need about 7–9 hours of sleep. Sleep debt accumulates: several short nights add up.
• Jet lag: the body clock adjusts by about one hour per day; flying east (advancing the clock) is usually harder than flying west.
• Fatigue slows reactions, narrows attention and makes people accept poorer performance. Being awake for 17–19 hours affects performance about as much as a blood alcohol level of 0.05%.
• Countermeasures: protect sleep before duty, strategic naps (keep them under about 30 minutes to avoid grogginess, or a full 90-minute cycle), controlled rest on the flight deck where the operator allows it, light, caffeine used wisely, and reporting fatigue honestly.

6. Stress

• Some stress improves performance; too much leads to tunnel vision, poor memory and rushed decisions.
• Sources: the flight itself (weather, failures), the organisation (schedules, pressure to be on time) and life outside work.
• Coping: preparation and training, sharing the workload, slowing down ("wind the clock"), and talking about it.

7. Automation

• Automation reduces workload but can cause complacency, mode confusion ("what is it doing now?") and loss of manual skills.
• Always know what mode the autopilot is in: read the flight mode annunciator aloud when it changes.
• Choose the right level of automation: if the automation is not doing what you want, go down a level – to selected modes, or to hand flying.

8. Personality and attitudes

People differ in how they lead, communicate and react to pressure. Recognising your own style helps you work with others. The hazardous attitudes from the PPL lesson – anti-authority, impulsivity, invulnerability, macho and resignation – matter even more in a crew, where one person's attitude affects everyone.

Flying it at Levant

Group flights and shared cockpit sessions on IVAO are a good place to practise CRM: brief each other, call out deviations, run checklists challenge-and-response. When flying alone, still brief yourself, read the FMA changes aloud, and stop a long session before fatigue makes the decisions for you.

Check yourself

1. What are the three levels of situational awareness? Perception, comprehension, projection (predicting).
2. When is alertness at its lowest? Around 02:00–06:00 body time.
3. Is a late runway change a threat or an error? A threat.
4. What should you do when the automation does something unexpected? Go down a level of automation and fly the aircraft.
5. Which direction of travel is usually harder for jet lag? Eastbound.

Simulation training material based on standard commercial human performance theory. It is not medical advice.