Monitored approaches

Principles underpinning these procedures can be successfully applied throughout all flight phases in new ways which lead to safer, more efficient and less costly operations.

By Don Van Dyke
ATP/Helo/CFII, F28, Bell 222
Pro Pilot Technical Editor, Canada

A common practice with many corporate flight departments and airline pilots, the monitored approach consists in having the FO/copilot as the heads-down pilot on the low-viz approach all the way to touchdown, while the seasoned captain monitors the approach and makes sure that the runway environment is clear and in sight.

Like learning a new language, the secret to mastering advanced airmanship is immersion in an operational environment in which we build on the foundation of high-fidelity training. Traditionally, a single pilot is assigned all aircraft handling for instrument approach, go-around and landing phases, as well as decision-making and overall flight management.

Pilot monitored approach (PMA) procedures were introduced in the 1970s to improve the transition from instrument to visual conditions, and to improve decision-making under high workloads. Early PMA procedures assigned one pilot (generally the captain) responsibility for overall management, decision-making, communicating, monitoring instrument flight during approach and go-around, and handling during visual landing. The other pilot (the FO) was made responsible for aircraft handling during instrument flight.

The absence of related ICAO Standards and Recommendations (SARPs) has allowed PMA implementation to vary widely among operators internationally. This article discusses the evolution of PMA procedures and proposes a number of amendments which may serve to extend and transform their application.

Monitoring and critical flight phases

In 1981, FAA enacted the sterile cockpit rule (FAR 121.542 and FAR 135.100) prohibiting crew member performance of non-essential duties or activities during critical phases of flight (taxi, takeoff, landing, and all other flight operations conducted below 10,000 feet MSL, except cruise flight).

EASA regulations on air operations (EU Regulation No. 965/2012 Annex I) do not specify the taxi phase as critical (except for helicopters) but do permit inclusion of any other phases of flight as determined by the PIC or commander. New Zealand includes pushback as a critical flight phase.

The sterile cockpit rule, while well-intentioned, complicated implementation of PMA procedures during critical flight phases by not clearly defining appropriate communication. The concept of sterile flight deck procedures is also introduced to some extent in ICAO Doc 9870 Manual on the Prevention of Runway Incursions (2007) which concluded that it is generally accepted that the need for a sterile cockpit commences as follows:

1. Departure: when the aircraft engine(s) start and ceases when the aircraft reaches 10,000 feet elevation above the departure aerodrome.
2. Arrival: when the aircraft reaches 10,000 feet elevation above the arrival aerodrome until engine(s) shut down after landing.
3. At any other times determined and announced by the flightcrew including inflight emergency and security alerts.

A 1994 NTSB study of crew-related accidents noted the problem of inadequate monitoring and challenging by FOs, particularly regarding captains' tactical decisions, concluding that eliminating this authority gradient is fundamental to PMA procedures. By 1997, British Airways implemented PMA procedures on all approaches, including full role reversal at the captain's discretion, thus avoiding or eliminating the authority gradient so vexing in earlier PMA implementations.

In 2009, NTSB noted that despite FAA not requiring operators to modify their procedures, carriers increasingly adopted PMA techniques. However, a reverse trend was also identified among merged operations involving North American carriers using PMA procedures with others which did not. The resulting merged carrier standardized, for various reasons, on use of traditional pilot flying (PF)/pilot monitoring (PM) procedures.

What is monitoring?

This simplified flightpath monitoring (FPM) model identifies the flow of management, observation, evaluation and intervention tasks to be performed in order to achieve agreed flight goals. The model also provides for inflight replanning to accommodate goals with agreed modifications.

Monitoring is the observation of crew, flight (aircraft systems, energy state, configuration, environment, etc) and automation components and their evaluation based on agreed values, modes and procedures. Monitoring promotes continuous situational awareness (SA), correct decision-making, and appropriate aircraft maneuvering to achieve planned goals.

Humans are inherently poor at detecting infrequent events and the human mind is fallible. Fatigue depresses arousals levels, often resulting in complacency and a general malaise. Resulting errors may include misheard messages, incorrect appreciation of conditions or situations, memory slips and many other consequences.

The potential to make mistakes, to be wrong or to fail is a trait commonly shared by aviation infrastructure and aircraft systems as well as the flightcrew which they serve. Ineffective monitoring is compounded by poor workload management, fixation on other tasks, and failing to interleave multiple tasks adequately. Other barriers to effective monitoring may include lack of knowledge, poor situational awareness, confusion, time pressure, flight deck designs and SOPs, inadequate mental models of autopilot modes, and corporate cultures that do not emphasize monitoring.

A 2013 Flight Safety Foundation (FSF) study of line operations safety audit (LOSA) observations from over 14,000 flights revealed that flights with poor or marginal monitoring had 2-3 times more mismanaged errors and as many undesired aircraft states than flights with outstanding monitoring.

Reports from the FAA Aviation Safety Action Program (ASAP) and NASA Aviation Safety Reporting System (ASRS) reveal specific errors associated with ineffective monitoring — from altitude busts (deviations) to rare but potentially fatal stalls and runway incursions.

Accepting that errors are commonplace on the flight deck, the immediate objective is to detect, recognize and resolve them before the aircraft is placed in jeopardy or an undesired state. Combined studies from ICAO, FAA, UK CAA, Transport Canada and industry groups such as FSF conclude that flightpath monitoring (FPM) procedures can significantly improve fault tolerance through:


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