Flight Path Monitoring

Flight Path Monitoring

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Definition

Flight path monitoring means the observation and interpretation of the flight path data, aircraft-configuration status, automation modes and on-board systems appropriate to the phase of flight. It involves a cognitive comparison of real-time data against the expected values, modes and procedures. It also includes observation of the other pilot and timely intervention in the event of a deviation.

This definition covers anytime the aircraft is in motion, including during taxi. It also includes continuous awareness of both the trajectory and energy state of the aircraft.

Description

Monitoring covers an extensive behavioural skill set that all pilots are expected to apply in the cockpit. The designated Pilot Flying (PF) is responsible for flying the aircraft in accordance with the operational brief and for monitoring the flight path. The Pilot Monitoring (PM) will have an explicit set of activities designated by the Standard Operating Procedures (SOPs) , and as such will have a specific and primary role to monitor the aircraft’s flight path, communications and the activities of the PF. Both pilots are responsible for maintaining their own situation awareness gained through cross-checking each other’s actions, communication of intent and diligent observation of the PF selections, mode activations and aircraft responses. Predictive monitoring supports anticipation of expected threats and the mitigation of consequences. Reactive monitoring enables the identification of unexpected/pop-up threats and mitigation of consequences; the detection and correction of errors; and the recognition of and recovery from undesired aircraft states.

Techniques

The cognitive processes engaged during monitoring are complex and involve the selective application of mental resources to encode the sensory inputs whilst performing a goal directed task. The senses relating to flight path monitoring are mainly visual and auditory, but tactile inputs from the flight controls (e.g. stick shaker, aeroplane buffet, etc.) can influence the monitoring task particularly in the event of a stall. Similarly, the smell and taste senses can alert the flight crew to fumes in the cockpit and therefore also perform a monitoring stimulus. Intent also forms an important part of monitoring and provides a baseline against which to monitor. Intent relates to system behaviour (what it is going to do), aircraft handling (predicted flight path/aircraft manoeuvrability) and Pilot Flying’s intent (the plan). Timely, accurate monitoring activities will result in outputs that, following crew judgement and decision making, can take the form of:

  • Verbalization to other pilot or self;
  • Non-verbal communication in the form of gesture/eye contact;
  • Note-taking in the case of auditory monitoring;
  • Reinforcement of collective situation awareness; and,
  • Maintenance of the mental model of the aircraft state.

Regarding physical ergonomics, pilots must be able to see and hear all information relevant to their monitoring tasks. Their seat positions must be adjusted to the design eye position to enable each pilot to view the internal displays and controls whilst maintaining an adequate view of the external scene. The optimal seat position is usually set by reference to two small balls on the central windscreen pillar. The balls appear aligned only when the pilot’s eye is at the design position.

Vision is a very complex subject and involves the ability of the eye to adapt to different lighting levels (called adaptation), focus on the information (normally referred to as accommodation) and to perceive information, such as texts and graphics, as legible at the required viewing distance (called visual acuity). Adaption, accommodation and acuity all vary with, and are affected by, age. Pilots need to be aware if they are experiencing any difficulty with focus, adaption or legibility of the displayed information as this will certainly compromise the monitoring task. Medical professionals will be able to advise on correction or treatment if necessary.

Hearing can be impaired by accumulation of wax in the outer ear (which is easily remedied), a head cold which blocks the Eustachian tube and prevents equalization of pressure or by infections in the middle ear. Hearing can be expected to deteriorate with age particularly with the higher frequencies. In addition, high ambient noise environment or distractions/interruptions in the cockpit can impact the clarity of aural messages. Under all circumstances, if there is any ambiguity related to information received aurally then ask for it to be repeated.

New technologies such as electronic flight bags (EFBs) allow for greater situational awareness both on the ground and in flight. Many navigational apps such as Jeppesen FliteDeck Pro can show aircraft position displayed against relevant charts and airport diagrams. This capability provides at-a-glance monitoring at any point from engine startup to completion of flight and engine shutdown.

Barriers to Monitoring

Many factors hamper monitoring, including system and ergonomic design, organisational factors and external environment. But the biggest concern relates to human vulnerabilities, such as complacency/inattention, distraction, low attentional resource, low arousal, disorientation, tiredness etc, and stressors (i.e., workload, etc.). These concerns arise from some relatively recent accidents and incidents.

Safety experts emphasize that it can be difficult for humans to effectively monitor for errors and deviations on a continuous basis when errors and deviations rarely occur, particularly in a highly automated environment. This holds true over the range of workload conditions experienced by the flight crew members. Monitoring during high-workload periods is critical because these periods present situations in rapid flux and because high workload increases vulnerability to error. However, studies show that poor monitoring performance can be present during low-workload periods as well. Lapses in monitoring performance during lower-workload periods are often associated with boredom, complacency, or both.

Potential challenges and barriers to effective monitoring include:

  • Time Pressure – Time pressure can exacerbate high workload and increase errors. It can also lead to rushing and “looking without seeing."
  • Lack of Feedback – When monitoring lapses occur, pilots are often unaware that monitoring performance has degraded.
  • Design of SOPs – Procedures may fail to explicitly address monitoring tasks.
  • Automation – Pilots’ inadequate mental model of autoflight system modes. Pilots may not have a complete or accurate understanding of all functions and behaviours of the autoflight system. Some aspects of automated systems for flightpath management are not well matched to human information processing characteristics.
  • Training – Training may overlook the importance of monitoring and how to do it effectively. Lack of emphasis on monitoring may occur in training and evaluation.

Solutions

While different types and levels of pilot training may involve pilots with differing levels of competence, the training of flight path monitoring should include uniform objectives and standards. Therefore, because the same monitoring concepts apply to all pilots, course content should not differentiate between different types of training courses. A graduated approach should be taken in developing an integrated pilot monitoring training program. It should start with solid grounding in theoretical knowledge, followed by instructor-led case studies. This should include videos and finally line-oriented flight training (LOFT), progressively building on each layer of content:

  • Knowledge – Without proper knowledge of systems and automation, the flight crew will not be able to understand nor predict the aircraft’s behaviour.
  • Skill – Without the necessary skills to operate the aircraft effectively, a flight crew will be overwhelmed by the flight path monitoring tasks.
  • Discipline – Discipline is a foundation for monitoring. Adherence to division of duties is essential for managing workload.
  • Attitude – Developing the right attitude often is the most important aspect of a training program.

Monitoring requires motivation and discipline and must be a continuous effort. The primary aim for flight crew members should be to effectively monitor the flight path, but first, flight crews must be well-trained in flying skills, discipline and behaviours . Without these, effective monitoring may not be possible.

Accidents & Incidents

DH8C, Sandy Lake ON Canada, 2022

On 19 October 2022, an unstable approach to Sandy Lake by a de Havilland DHC8-300 was followed by a mishandled landing attempt by the First Officer involving excessive pitch up and a tail strike and when the Captain recognised a go-around was intended, he took over and completed the landing. The Captain had recently been promoted after 3,000 hours as a First Officer and the First Officer had just been released on his first two-pilot aircraft type after over 70 hours line training. Regulatory oversight appeared not to have detected that the operator’s safety management system was comprehensively unfit for purpose.

B772 / B739, New York JFK USA, 2023

On 13 January 2023, in good night visibility, an augmented crew Boeing 777-200 failed to comply with its departure taxi clearance and with its Captain taxiing crossed a runway in front of a 737 taking off. ATC responded to an automated conflict warning by cancelling the takeoff clearance and a high speed rejected takeoff was initiated from approximately 105 knots with minimum separation as the 777 cleared the edge of the 737 takeoff runway approximately 300 metres. The Investigation concluded that the 777 operator’s risk controls and the airport’s methods for detecting and preventing dangerous runway conflicts were both inadequate.

AT76, Jabalpur India, 2022

On 12 March 2022, an ATR76-600 Captain made an unstabilised approach to Jabalpur before a first bounce more than half way along the runway and a final touchdown 400 metres from the runway end. The First Officer took control but did not commence a go-around and the aircraft overran the runway before stopping. The Captain had just over four months command experience and had made six similar ‘high-severity long-flare’ approaches in the previous five days but these had gone undetected because although such exceedances were supposedly being tracked by company flight data monitoring, this event was not being tracked.

B737, Las Vegas USA, 2023

On 16 February 2023, a Boeing 737-700 took off from Las Vegas in excellent night visibility aligned with the right hand runway edge lights instead of the unlit centreline without pilot awareness during or after the takeoff. Minor nosewheel tyre damage found after flight did not trigger an operator investigation and the airport only discovered the runway edge lighting damage two days later and did not identify and advise the operator until over a week had passed. The very experienced Captain had misaligned the aircraft whilst the extremely inexperienced First Officer was too busy to monitor the Captain’s actions.

A320, Copenhagen Denmark, 2022

On 8 April 2022, an Airbus A320 made a multiple bounce touchdown at Copenhagen followed by thrust reverser deployment. The Captain rejected the landing and began a go-around but as the left main gear had bounced and was not on the ground when thrust was set, the left engine reverser did not stow. Full aircraft control was briefly lost and a runway excursion narrowly avoided before a recovery to a single engine MAYDAY circuit and landing followed. Engine software design prevented thrust reverser stowage without weight on wheels which was why rejected landings after reverser deployment were prohibited.

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