Modern aircraft are increasingly dependent on automation for safe and efficient operation. However, automation also has the potential to cause significant incidents when misunderstood or mishandled. In addition to that, automation may result in an aircraft developing an undesirable state from which it is difficult or impossible to recover using traditional hand flying techniques.
Automation Advantages
- Increases passenger comfort;
- Improved flight control;
- Systems monitoring displays coupled with diagnostic assistance systems support enhanced pilots’ and maintenance staff’s understanding of aircraft system states.
- Automation can relieve pilots from repetitive tasks for which humans are less suited, though it invariably changes the pilots’ active involvement in operating the aircraft into a monitoring role, which humans are particularly poor at doing effectively or for long periods. As an example, pilots who fly with Autothrottle (AT) engaged can quickly lose the habit of scanning speed indications.
- Automation reduces workload, and pilots can focus on other tasks.
Flight Crew - Automation Interaction Problems
- Basic manual flying skills can decline because of lack of practice and feel for the aircraft.
- Unexpected automation behavior: uncommanded disengagement caused by a system failure resulting in mode reversion or inappropriate mode engagement by the pilot may lead to adverse consequences;
- Pilots interacting with automation can be distracted from flying the aircraft;
- Flight crews may spend too much time trying to understand the origin, conditions, or causes of an alarm or of multiple alarms, which may distract them from other priority tasks and from flying the aircraft;
- Short notice changes by ATC requiring reprogramming of a departure or landing runway are potentially hazardous due to the possibility of incorrect data entry and crosschecking in a time critical situation.
- Situations requiring manual override of automation are difficult to understand and manage, can create a surprise or startle effect, and can induce peaks of workload and stress.
- For highly automated aircraft, problems may occur when transitioning to degraded modes (e.g. multiple failures requiring manual or less automated flight);
- Errors may be more difficult to prevent and detect;
- In critical situations following disconnection or failure of the automation, the alarm system only indicates the condition met but not the action to take;
- It may be difficult to understand the situation and to gain/regain control when automation reaches the limit of its operation domain and disconnects or in case of automation failure;
Automation Dependency
Automation Dependency has commonly been described as a situation in which pilots who routinely fly aircraft with automated systems are only fully confident in their ability to control the trajectory of their aircraft when using the full functionality of such systems. Such a lack of confidence usually from a combination of inadequate knowledge of the automated systems themselves;
Safety Issues
Two problems arise directly from automation dependency:
Firstly, affected pilots are reluctant to voluntarily reduce the extent to which they use full automation capability to deal with any situation - routine or abnormal - which arises.
Secondly, if the full automation capability is for some reason no longer available or it is considered that it is no longer capable of delivering the required aircraft control, then the tendency is to seek to partially retain the use of automated systems rather than revert to manual aircraft trajectory control. The effect is often a loss of situational awareness triggered by Excessive workload for both pilots. The consequence of this is frequently a reduction in the extent to which the PM is able to effectively monitor the actions of the PF.