Stress is a bodily response to a stimulus that disturbs or interferes with the “normal” physiological equilibrium of a person and, in the context of aviation, refers to a state of physical, mental or emotional strain due to some external or internal stimulus.
Understanding the factors that lead to stress, as well as how to cope with stressful situations, can greatly improve a individual's performance. Also, understanding that colleagues may react differently to the same stressor is important and can help you control a situation that can quickly get out of hand if an individual is having a negative reaction.
Accidents & Incidents
Events on the SKYbrary database which list stress as a significant contributory factor:
On 12 September 2020, during a largely autopilot-controlled ILS glideslope capture from above and despite being unstabilised after the crew had intentionally ignored required approach management procedures, a flight was continued without hesitation to a landing. The Investigation found that the operator’s oversight of operating standards relating to unstabilised approaches was systemically flawed and also insufficiently supportive of their ‘Evidence Based Training’ method used for pilot training. It was also noted that the Captain involved had stated to the Investigation that “he considered this flight as a non event”.
On 18 July 2018, an Airbus A330-300 failed to reject its night takeoff from Brisbane despite the absence of any airspeed indication for either pilot. A PAN call was made as a climb to FL110 continued. Once there, preparations for a somewhat challenging return were made and subsequently achieved. The Investigation noted multiple missed opportunities, including non-compliance with several procedural requirements, to detect that all pitot mast covers had remained in place and was extremely concerned that the takeoff had been continued rather than rejected. Flawed aircraft operator ground handling procedures and ineffective oversight of contractors were also deemed contributory.
On 15 August 2018, a Boeing 737-300SF crew concerned about a small residual pressure in a bleed air system isolated after a fault occurred en-route then sought and were given non-standard further troubleshooting guidance by company maintenance which, when followed, led directly and indirectly to additional problems including successive incapacitation of both pilots and a MAYDAY diversion. The Investigation found that the aircraft concerned was carrying a number of relevant individually minor undetected defects which meant the initial crew response was not completely effective and prompted a request for in-flight assistance which was unnecessary and led to the further outcomes.
On 2 September 2019, a Boeing 777-300 failed to continue climbing following a night takeoff from Shanghai when the autopilot was quickly engaged. When it began to descend, inaction after several EGPWS DON’T SINK Alerts was followed by an EGPWS ‘PULL UP’ Warning. Recovery then followed but only after autopilot re-engagement led to another descent did the crew recognise that a single character FMS data input error was the cause. The Investigation was concerned that both pilots simultaneously lost situational awareness of the low aircraft altitude during the event and noted both procedural non-compliance and sub-optimal crew interaction.
On 23 February 2018, an Embraer 195LR and an Airbus A320 on SIDs departing Brussels lost separation after the 195 was given a radar heading to resolve a perceived third aircraft conflict which led to loss of separation between the two departing aircraft. STCA and coordinated TCAS RA activations followed but only one TCAS RA was followed and the estimated minimum separation was 400 feet vertically when 1.36 nm apart. The Investigation found that conflict followed an error by an OJTI-supervised trainee controller receiving extended revalidation training despite gaining his licence and having almost 10 years similar experience in Latvia.
On 23 February 2019, a Boeing 767-300 transitioned suddenly from a normal descent towards Houston into a steep dive and high speed terrain impact followed. The Investigation found that after neither pilot had noticed the First Officer’s inadvertent selection of go around mode during automated flight, the First Officer had then very quickly responded with an increasingly severe manual pitch-down, possibly influenced by a somatogravic illusion. He was found to have had a series of short air carrier employments terminating after failure to complete training, had deliberately and repeatedly sought to conceal this history and lacked sufficient aptitude and competency.
On 19 December 2008, an Aeroflot Airbus A320 descended significantly below its cleared and acknowledged altitude after the crew lost situational awareness at night whilst attempting to establish on the ILS at Oslo from an extreme intercept track after a late runway change and an unchallenged incorrect readback. The Investigation concluded that the response to the EGPWS warning which resulted had been “late and slow” but that the risk of CFIT was “present but not imminent”. The context for the event was considered to have been poor communications between ATC and the aircraft in respect of changes of landing runway.
On 10 February 2011, control of a Spanish-operated Fairchild SA227 operating a scheduled passenger flight from Belfast UK to Cork, Ireland was lost during an attempt to commence a third go around due to fog from 100 feet below the approach minimum height. The Investigation identified contributory causes including serial non-compliance with many operational procedures and inadequate regulatory oversight of the Operator. Complex relationships were found to prevail between the Operator and other parties, including “Manx2”, an Isle of Man-based Ticket Seller under whose visible identity the aircraft operated. Most resultant Safety Recommendations concerned systemic improvement in regulatory oversight effectiveness.
On 17 July 2011, an Aer Arann ATR 72-200 made a bounced daylight landing at Shannon in gusty crosswind conditions aggravated by the known effects of a nearby large building. The nose landing gear struck the runway at 2.3g and collapsed with subsequent loss of directional control and departure from the runway. The aircraft was rendered a hull loss but there was no injury to the 25 occupants. The accident was attributed to an excessive approach speed and inadequate control of aircraft pitch during landing. Crew inexperience and incorrect power handling technique whilst landing were also found to have contributed.
On 18 November 2009, an IAI Westwind on a medevac mission failed to make a planned night landing at Norfolk Island in unanticipated adverse weather and was intentionally ditched offshore because of insufficient fuel to reach the nearest alternate. The fuselage broke in two on water contact but all six occupants escaped from the rapidly sinking wreckage and were eventually rescued. The Investigation initially completed in 2012 was reopened after concerns about its conduct and a new Final Report in 2017 confirmed that the direct cause was flawed crew decision-making but also highlighted ineffective regulatory oversight and inadequate Operator procedures.
On 16 September 2007, an MD-82 being operated by One Two Go Airlines attempted a missed approach from close to the runway at Phuket but after the flight crew failed to ensure that the necessary engine thrust was applied, the aircraft failed to establish a climb and after control was lost, the aircraft impacted the ground within the airport perimeter and was destroyed by the impact and a subsequent fire. Ninety of the 130 occupants were killed, 26 suffered serious injuries and 14 suffered minor injuries.
On 1 September 2018, a Boeing 737-800, making its second night approach to Sochi beneath a large convective storm with low level windshear reported, floated almost halfway along the wet runway before overrunning it by approximately 400 metres and breaching the perimeter fence before stopping. A small fire did not prevent all occupants from safely evacuating. The Investigation attributed the accident to crew disregard of a number of windshear warnings and a subsequent encounter with horizontal windshear resulting in a late touchdown and noted that the first approach had meant that the crew had been poorly prepared for the second.
On 15 February 2013, an Embraer EMB-500 Phenom 100 crew lost control of their aircraft shortly before touchdown at Berlin Schönefeld when it stalled and crash-landed. The Investigation was not completed for almost six years but concluded that the stall was a result of ice accretion during an approach in icing conditions without activation of the airframe de icing system. It found poor crew awareness of both the ice and stall protection systems and, suspecting that this may be true of other type-rated pilots, accordingly made Safety Recommendations to key regulatory authorities concerning the type rating syllabus.
On 27 March 2016 an ATR 42-500 had just departed Esbjerg when the right engine flamed out. It was decided to complete the planned short flight to Billund but on the night IMC approach there, the remaining engine malfunctioned and lost power. The approach was completed and the aircraft evacuated after landing. The Investigation found the left engine failed due to fuel starvation resulting from a faulty fuel quantity indication probably present since recent heavy maintenance and that the right engine had emitted flames during multiple compressor stalls to which it was vulnerable due to in-service deterioration and hot section damage.
On 30 September 2018, an Airbus A319 Captain had to complete a flight into Glasgow on his own when the First Officer left the flight deck after suffering a flying-related anxiety attack. After declaring a ‘PAN’ to ATC advising that the aircraft was being operated by only one pilot, the flight was completed without further event. The Investigation found that the First Officer had been “frightened” after the same Captain had been obliged to take control during his attempted landing the previous day and had “felt increasingly nervous” during his first ‘Pilot Flying’ task since the event the previous day.
Related OGHFA Situational Examples
|Situational Example||Flight Phase|
|De-icing and Latent Organisational Factors (OGHFA SE)||Take Off|
|Disorientation During Vectored Go-Around (OGHFA SE)||Missed Approach|
|Fuel Leak and Confirmation Bias (OGHFA SE)||Climb, Cruise, Descent|
|Fuel Starvation, Stress, Fatigue and Nonstandard Phraseology (OGHFA SE)||Cruise, Descent|
|Landing Gear Failure (OGHFA SE)||Landing|
|Takeoff Weight Entry Error and Fatigue (OGHFA SE)||Take Off|
|Unidentified Fire On Board (OGHFA SE)||Cruise, Descent, Landing|
Related OGHFA Material
- Human Factors Module: Stress
- Managing Stress in ATM, EUROCONTROL, March 2020
- Flight Safety Australia: Fit to Fly?
- Fighting Pilot Fatigue, video by Boeing’s Fatigue Risk Management team in partnership with Delta airlines to portray the effects of fatigue on pilots. It describes technologies in the flight deck that can monitor and prevent fatigue-related events.
- Safety Behaviours: Human Factors Resource Guide for Engineers, CASA (Australia), 2013. Chapter 6 deals with stress for maintenance personnel.