Single Pilot Operations: Automation and Workload Management

Introduction

The number of aviation pilots has been decreasing over the past few years as technology has assumed most cockpit functions to reduce workload. Over the preceding three decades, the standard crew complement in commercial aviation aircraft has been two pilots (Boy, 2014); however, debate continues about whether further reductions should be considered — replacing additional human functions with automated systems. This paper investigates the high workload tasks in aviation aircraft that could be identified and automated so that workload management for one pilot is more manageable and single-pilot operations (SPO) can be safely supported.

Problem Statement and Research Goals

Recently, efforts have been made to reduce the number of crew members in air carrier transport airlines from two to one. The rationale is that automating most tasks would allow a single pilot to manage workload safely. However, it is essential to identify the high workload tasks so that appropriate automation can be provided for better aviation management and reduced costs. Research efforts and resources would be directed toward determining these workloads in order to formulate effective technologies, procedures, and pilot training. The required automation for safely achieving single-pilot operations is attainable only when equipment and training are well-established.

The central question guiding this research is: what workload tasks require automation to enable single-pilot operations? This question facilitates the search for information leading to an understanding of which workloads could be handled safely by a single pilot instead of two.

The research question for this study is as follows:

What tasks are considered "high workload tasks" such that their automation could ease workload management for a two-pilot crew and support a reduction to a single pilot?

If the high workload tasks are specified, then automation would improve workload management by a single pilot, and the transition to SPO would be more feasible and convenient.

Literature Review

Research has demonstrated various benefits of having at least two pilots in passenger or cargo aircraft, as they share the management of workload. The human factor must be addressed when automating workload tasks, since final decisions remain with the pilot — even in critical situations and emergencies. Where the human factor is present, there exists the potential for error, as situations may arise in which a rule or procedure is not followed, resulting in an unwanted emergency.

A study was conducted to evaluate the effectiveness of LOSA (Line Operations Safety Audit), a multi-crew management system, and its feasibility for application in single-pilot operations (Earl et al., 2012). The study investigated errors that pose threats to flights and found that errors such as intentional non-compliance, communication failures, procedural mistakes, and aircraft mishandling were prominent. The associated threats included weather management, aircraft automation issues, operational pressures for environmental handling, loss of control in air traffic, and adverse conditions at the airport.

Another study indicated that risk factors for aircraft accidents include fatigue, high workload, distraction, automation confusion, insufficient training in automation, pressure during emergencies, and unsatisfactory situational awareness (Yan, 2014). Effective communication can reduce many of these risks — managing distraction, mitigating low performance during high-workload tasks, and providing support particularly in emergencies such as fire or severe weather conditions. Like high workload, fatigue is a human factor capable of causing catastrophe in aviation, and it is difficult to monitor through automated systems alone.

Interviews with pilots have revealed that they value the presence of a co-pilot, as interpersonal bonding plays a meaningful role in releasing mental pressure (Vu et al., 2018). A co-pilot helps maintain situational awareness and relieves the boredom of flying alone, while also helping manage stress. One study concluded that even as automation sophistication increases in modern aviation, the presence of a lone pilot would likely lead to boredom and adversely affect attention levels — even in managing automated systems (Bhana, 2010).

Generally, the two-pilot operations in a commercial aircraft encompass aviation tasks, navigation, communication and coordination, and management of system state (Lim et al., 2017). Specific criteria must be considered before reducing crew members from two to one. The workload factors and functions central to these criteria include controlling the flight path, preventing collisions, communicating with the ground crew, controlling aircraft systems and monitoring the engine, making decisions about commands, and navigation (Sulzer, Cox & Mohler, 1981).

The factors that contribute to increased workload for a minimum crew include maintaining constant power and engine controls, managing emergencies such as fire or severe weather, addressing system or device malfunctions, managing the complexity of multiple simultaneous functions, the urgency required to fulfill those functions, the mental and physical pressure on a single pilot to normalize flight operations, and the likelihood of a further increase in workload during an emergency.

According to the NASA Task Load Index (TLX), six workload subscales were identified: mental demand, physical demand, temporal demand, frustration, performance, and effort (Casner & Gore, 2010). This model's advantage is that it captures pilots' perceptions of their own workload, enabling a more accurate assessment of tasks that could be automated for single-pilot operations. Although the method carries some risk of personal bias in workload identification, it remains effective in identifying tasks based on personal experience.

To address the shortcomings of the TLX method, the Bedford method can be employed. Its primary advantage is the inclusion of ratings with corresponding interpretations — when a pilot assigns a rating to a workload, the relevant interpretation provides sufficient explanation. However, the same limitation applies: pilot judgment is involved in assigning ratings, which introduces subjectivity.

Additionally, concern has been raised that if the number of pilots is reduced from two to one, and greater reliance is placed on the human factor alongside automation, the single pilot must be thoroughly qualified and trained for the role. A study with a high reliance on NASA simulation data (Bailey et al., 2017) found that single-pilot operations increased workload compared to two-pilot crew arrangements, as all decisions had to be made by a lone pilot — decisions that can be subjective based on that pilot's individual assessment of safety. Though pilots are well-trained, they must be in a state capable of addressing emergency threats in air transport operations.

Additional flight factors have been assessed as contributors to pilot workload. Research examining human errors as major drivers of workload stress and reduced performance found that flying over a populated area and maintaining a suitable gliding angle are significant concerns (Lee, 2010). New procedures and compliance with those procedures in such demanding conditions further compound pilot workload challenges.

Conclusion and Recommendations

The hazards of single-pilot operations must be weighed against their potential benefits. If the advantages outweigh the risks, SPO would represent a feasible cost-reduction strategy for the future. A one-time investment in advanced automated systems could yield higher long-term profits, provided those systems are accurately managed and rigorously verified, and that only highly experienced, well-trained pilots occupy the cockpit.

Certain risks are inherent in high workload management: a single pilot may misjudge a situation or experience communication breakdowns under pressure. Communication distortion can occur when the pilot's attention is consumed by an emergency — such as severe weather or an onboard fire — leaving insufficient capacity to process details communicated from the ground crew. Automation of workload tasks can relieve a single pilot from some of these pressures; however, challenges such as boredom, reduced attention, non-compliance during periods of low focus, and fatigue require careful management, as they are difficult to monitor through automated means alone.

Following a detailed analysis of the literature and the themes derived from secondary data, it is recommended that high levels of communication be maintained between the single pilot and the ground crew if single-pilot operations are to be adopted. Even the most advanced machine cannot be fully trusted; automated systems can malfunction at any time, particularly during emergencies such as onboard fires — when all automated systems may cease to function at precisely the most critical moment. In such scenarios, the lone pilot would rely solely on personal judgment and subjective decision-making skills.

Uninterrupted communication would help keep a single pilot attentive throughout a flight if reduced crew operations are implemented. Certain functions are well-suited for automation — such as flight path navigation, collision avoidance, regulation of aircraft systems and engine monitoring, and decision-making regarding system commands. However, the challenge of pilot boredom, reduced attentiveness to automated alerts, and diminished compliance with system prompts must also be addressed. Increased human errors can be mitigated through uninterrupted communication with the ground crew and through robust, ongoing training programs tailored to the demands of single-pilot operations.

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