12.1 Human Performance, IMSAFE & Crew Resource Management

Human Performance, IMSAFE & Crew Resource Management

Quick Summary: Human error contributes to over 70% to 80% of civil aviation occurrences. In remotely piloted aviation, physical separation from the aircraft creates sensory decoupling, making pilots reliant on visual monitoring and cognitive discipline. Under CAR 901.19, flight crew members must adhere to strict fitness-to-fly rules, including a mandatory 12-hour alcohol abstinence window. Using tools like the IMSAFE checklist, the Swiss Cheese accident model, and Crew Resource Management (CRM) principles ensures RPAS operators prevent human-factor failures before flight.

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Human Factors & Aviation Safety Philosophy

The field of Human Factors in aviation optimizes the relationship between human operators, technological interfaces, operational environments, and procedures. Unlike crewed aircraft pilots who receive continuous vestibular and tactile cues, RPAS pilots operate under sensory decoupling—they lack physical motion sensations and engine vibrations, relying entirely on visual line-of-sight (VLOS), telemetry displays, and cognitive discipline.

The Swiss Cheese Model of Accident Causation

Developed by psychologist James Reason, the Swiss Cheese Model explains how complex systems fail. Aviation safety relies on multiple defensive layers (regulations, standard operating procedures, pilot training, and aircraft fail-safes):

• Defensive Layers: Each defense acts as a slice of cheese designed to prevent hazards from turning into accidents.
• Latent Conditions: Inherent, dormant weaknesses within the organization or system (e.g., poor maintenance schedules, vague SOPs, commercial time pressure, or inadequate training).
• Active Failures: Unsafe acts committed directly by the operational flight crew (e.g., omitting a pre-flight check, flying while fatigued, or misreading telemetry).
• Trajectory of Accident Causation: An accident occurs when holes in each defensive layer momentarily align, allowing a hazard vector (such as a sudden gust or battery failure) to pass through unobstructed, causing a crash or flyaway.

Situational Awareness (Endsley Model)

Situational Awareness (SA) is defined by Dr. Mica Endsley as the perception of environmental elements, comprehension of their meaning, and projection of their future status. Loss of situational awareness is a primary root cause of RPAS accidents.

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Fatigue & Workload Management

Fatigue impairs alertness, motor reflexes, and decision-making. RPAS operations demand intense concentration, making operators particularly vulnerable to workload-induced fatigue.

Acute Fatigue vs. Chronic Fatigue

Physical and Cognitive Degradation

Fatigued pilots suffer from attention tunneling (fixating on a camera monitor while ignoring airspace), slowed reflexes (delayed response to wind shear or obstacles), complacency (skipping pre-flight walkarounds), and impaired risk calculation (flying beyond line-of-sight or inside bystander buffers).

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The IMSAFE Self-Assessment Checklist

Transport Canada promotes the standardized IMSAFE checklist for pre-flight pilot fitness evaluation:

• I — Illness: Are you suffering from an active illness, viral infection, or sinus congestion? Head congestion impairs visual tracking and spatial orientation. If unwell, do not fly.
• M — Medication: Have you taken prescription or over-the-counter (OTC) drugs? Common medications like sedating antihistamines (e.g., diphenhydramine) or cold remedies induce extreme drowsiness and blurred vision. Always verify medication is flight-approved.
• S — Stress: Are personal, financial, or workplace pressures clouding your judgment? Stress induces cognitive distraction, rushing, and impulsive decision-making.
• A — Alcohol: CAR 901.19 mandates that no person shall act as an RPAS crew member within 12 hours of consuming an alcoholic beverage. Furthermore, CAR 901.19(2)(b) and (c) prohibit acting as a crew member while under the influence of alcohol, or while using any drug that impairs the person's faculties to the extent that aviation safety or the safety of any person is endangered. There is no numeric blood-alcohol limit in Part IX — zero residual hangover impairment is the operative test, and the TC AIM adds a 28-day abstinence expectation for cannabis.
• F — Fatigue: Have you had adequate, restorative sleep? Operating during circadian lows (02:00–06:00 or post-lunch) significantly degrades vigilance.
• E — Eating / Emotion: Are you properly hydrated and nourished? Low blood sugar causes shakiness, irritability, and poor judgment. Are you emotionally agitated or rushing?

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Crew Resource Management (CRM) in RPAS Operations

Crew Resource Management (CRM) optimizes the use of personnel, hardware, and operational procedures to maximize safety.

Single-Pilot vs. Multi-Crew CRM

• Single-Pilot Operations: The lone pilot must manage flight control, airspace scanning, telemetry monitoring, and navigation. Single-pilot CRM relies on strict checklist discipline, automated battery alarms, and deliberate pacing to avoid task saturation.
• Multi-Crew Operations: Complex missions utilize a Pilot-in-Command (PIC), a Visual Observer (VO), and a Sensor Operator (SO). Under CAR 901.28(b), each crew member must be instructed on the duties they are to perform and on the location and use of any emergency equipment before acting as a crew member, and under CAR 901.23(3) the normal and emergency procedures must be reviewed before the flight by, and be immediately available to, every crew member. The PIC retains ultimate legal authority.

Communication Protocols & Sterile Cockpit

• Standardized Verbal Callouts: Concise, clear phrases eliminate confusion (e.g., "Airspace clear," "Takeoff committed," "Battery 50 percent," "Traffic, left 9 o'clock").
• Closed-Loop Communications: Using a readback-hearback protocol ensures critical commands are understood. When the PIC calls "Descend to 100 feet," the crew member reads back "Descending to 100 feet," followed by the PIC's confirmation ("Affirmative").
• The "Sterile Cockpit" Rule: During critical flight phases—system checks, motor arming, takeoff, landing approach, and transit near obstacles—all non-essential conversation, phone calls, and distractions must cease completely.

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Practical Exam Scenarios & Common Traps

• The Morning Hangover Trap: A pilot consumed beer 13 hours ago, but wakes up with a severe headache and nausea. Even though the 12-hour abstinence period has passed, flying violates CAR 901.19(2)(b) due to residual physiological impairment.
• The Non-Drowsy Decongestant Trap: A pilot with severe allergies takes a cold medicine containing sedating antihistamines. Flying while experiencing medication-induced drowsiness violates Canadian aviation fitness requirements.
• The Multitasking Visual Observer Trap: Diverting the Visual Observer to ground photos or client questions breaks the reliable, timely lookout and communication that CAR 901.20 depends on. TC AIM RPA 3.2.8 tells the pilot to use a second visual observer or land until the task is complete.