Reports
Beyond ‘Time on Task’
Flight Attendant Fatigue, Part I: National Duty, Rest, and Fatigue Survey
Avers, Katrina Bedell; King, S. Janine; Nesthus, Thomas E.; Thomas, Suzanne; Banks, Joy. U.S. Federal Aviation Administration (FAA) Civil Aerospace Medical Institute (CAMI). Report no. DOT/FAA/AM-09/24. December 2009. 23 pp. Figures, references.
At the instigation of the U.S. Congress, CAMI has been studying flight attendant fatigue in connection with six research topics recommended in an initial report in 2007. A report on the sixth topic, fatigue countermeasures, was published previously (ASW, 11/09, p. 55), while the first of those recommendations, a “national survey of flight attendant field operations,” led to this report.
To frame its findings, the report says, “It is important to recognize that fatigue is more than sleepiness or tiredness. Fatigue has psychological, physiological and emotional implications that can impact the performance of safety-related duties, particularly during non-routine and emergency events.”
Results were tallied from 9,180 cabin crewmembers who voluntarily and anonymously completed the survey. Among those who reported experiencing fatigue while on duty, 71 percent believed that their safety-related performance was affected, the report says. “Of those, 60 percent believed [that] their ability to respond to passenger needs — including service and safety-related items — was compromised, 36 percent reported cabin safety performance — e.g., arming/disarming doors, verifying seatbelts fastened — was affected, 34 percent felt their vigilance regarding cabin security … was impeded and 14 percent indicated [that] preflight safety briefings were affected.”
Current U.S. regulations require that flight attendants receive a minimum rest period of nine consecutive hours after a scheduled duty period of 14 hours or less, or 12 consecutive hours of rest following up to 20 duty hours. These rest periods, however, can be adjusted downward as a trade-off for longer subsequent rest periods. The report says that those rest periods, however, “do not take into account a number of operational issues that affect fatigue, such as time-zone transitions, layover and recovery, duty day start or end times, and the individual’s actual sleep need.” It adds that disruption of circadian rhythm — the body’s physiological “internal clock” — is a more important consideration in fatigue than “time on task.”
Duty time may involve unusually fatiguing situations not accounted for by the regulations. These situations can include ill or disruptive passengers, malfunctioning cabin or galley equipment, passenger luggage not easily stowed in the available bins, and severe turbulence.
This survey was conducted “to identify the specific operational factors that may contribute to fatigue in cabin crew operations.” Distributed to flight attendants representing 30 operators, the survey addressed each of the fatigue-related factors identified in a previous literature review. The factors were grouped into seven main topics: work background, workload and duty time, sleep “demographics” such as sleep at home and away from home, health, fatigue — including perceptions of fatigue, fatigue factors, fatigue effects and coping strategies — and demographic information about the flight attendants.
Although getting enough sleep is far from the only factor affecting fatigue, it is critical. The survey compared flight attendants’ sleep at home and away from home. The flight attendants rated sleep-interfering factors on a five-point scale from “not at all” to “great extent.” The average scores were higher for every factor in the “away” category. For example, “random noise” averaged 3.35 away, 1.89 at home. “Fear of oversleeping” averaged 3.21 and 2.06, respectively.
When asked to rate their overall quality of sleep away from home on a five-point scale from “very poor” to “very good,” 18 percent reported “good” or “very good,” 48 percent reported “fair” and 34 percent reported “poor” or “very poor.”
Asked if they experienced fatigue while on duty, 84 percent said they had been fatigued during their previous bid period, a work period that often accounts for one month of assignments. Slightly more than half acknowledged that they had “nodded off” — experienced a brief sleep or semi-sleep — during a flight segment.
The study delved into the subjective side of the fatigue experienced — what factors the flight attendants associated with the fatigue and how it affected them.
Among those who reported being fatigued, 44 percent identified workload as a contributing factor, 42 percent mentioned work pace and 83 percent said that their work schedule was associated with fatigue.
“Flight attendants were given a list of 44 specific events … believed to contribute to fatigue in aviation operations,” the report says. “They were asked to identify the frequency with which each event occurred [on a scale from 1 = never to 5 = always] and the extent to which each event contributed to their perceived fatigue [on a scale from 1 = not at all to 5 = very great extent].”
The 10 reported factors that most contributed to fatigue were a 14-hour or longer duty day; shift turnaround of less than nine hours; a 10- to 13-hour duty day; 14 or more consecutive duty days; short layovers; no breaks; missed meals; delays of three or more hours; and eight to 13 consecutive duty days.
“Examining the fatigue effect rating in conjunction with the frequency of occurrence, four of the top 10 factors received frequency ratings greater than ‘occasionally,’ including 10- to 13-hour duty day, missed meals, no breaks and short layovers,” the report says.
Among fatigue factors associated with the work environment, flight attendants rated lack of crew rest highest in how much it affected them, though not highest in frequency. In terms of effect, lack of crew rest was followed in decreasing order by contaminated cabin air, weather conditions, malfunctioning cabin equipment and high cabin temperature.
The breakdown of factors associated with scheduling patterns showed that a duty day of 14 hours or more had the greatest effect on fatigue, although not the greatest frequency. But a 10- to 13-hour duty day was rated high both on effect and frequency.
“The amount of time between flight legs, including short layovers, was identified as one of the top 10 contributors to fatigue that occurred frequently,” the report says. “Interestingly, two issues seem to be associated with layover length: first, short layovers that do not allow for meals or breaks; and second, extended waits between flight segments may contribute to long duty days with little flight time.”
Flight attendants had suggestions for reducing their fatigue while on duty. “Three changes were recommended more often than the others: Begin the rest period on arrival at the hotel, avoid multiple-hour breaks between flights and provide food and drink on flights,” the report says.
Starting the clock for rest periods when the airplane arrives at the gate is unrealistic, according to many flight attendants. “There are times when we are waiting for almost an hour for transportation and it’s completely out of our hands,” one wrote.
The report’s recommendations for fatigue reduction primarily concern scheduling and physiological factors.
“An overall review of scheduling practices may be an important part of any attempt to address fatigue,” the report says. “An examination of duty duration, continuous-duty overnights, reserve practices, reduced rest, breaks, rest periods and duty report times may be warranted.
“Missed meals accounted for the other key fatigue factor that was commonly identified by flight attendants. To some extent, this issue may be addressed by both flight attendants and by airlines. For example, airlines might provide fresh, healthy meals when flights have food service. Flight attendants, in turn, could plan ahead and generally bring healthy snacks aboard, although this is difficult during reduced-rest conditions with limited access or time to purchase food.
“Similarly, airlines could provide beverages, or flight attendants could bring some bottled water or other non-caffeinated beverage, but the issue of missed meals seems to be inherently tied to missed breaks or no breaks. In other words, preparation of a healthy meal can only be beneficial if the flight attendant has the opportunity to eat the meal.”
— Rick Darby
At the Accident Site
Civil and Military Aircraft Accident Procedures for Police Officers and Emergency Services Personnel
Australian Transport Safety Bureau and Australian Directorate of Defence Aviation and Air Force Safety. Edition 5, June 2010. 41 pp. Photographs, illustrations.
Police and emergency personnel have their own established procedures when they are first responders to an aircraft accident, but those procedures might not be optimal for a subsequent accident investigation or even for their own safety. “As a rescue officer you should be careful to avoid becoming a casualty yourself,” the guide says. “In the heat of the moment and the desire to alleviate suffering and minimize casualties, individuals sometimes place themselves at considerable personal risk of injury or death.”
This is the latest edition of a guide to best practices at the scene of a crash, which will be, for many, an unusual and distressing task. Although the instructions about notification and formal reporting are specific to Australia, many of the guidelines will be applicable in other countries.
“The first people to arrive at an aircraft accident site can significantly help minimize injury and loss of life, reduce property loss through damage and fire, and prevent loss of clues and evidence as to the factors that contributed to the accident,” the guide says. “To preserve evidence for an effective investigation, it is essential to appropriately manage and control the accident site.”
Site control includes observing standard hazardous materials (HAZMAT) procedures, the guide says. The area should be sealed off to unauthorized persons for at least 50 m (164 ft) around the wreckage.
The guide goes into considerable detail about the rescue of any survivors from crashed aircraft. Among the points listed are these:
- “Approach the site from upwind (with the wind at your back) and downhill, if possible, to avoid inhalation of burning materials, some of which are toxic, others of which can be very irritating to the breathing tract. Look around the crash site, along the crash path, and maintain a clear observation of the accident site and associated hazards;
- “Render first aid and care to survivors until medical personnel arrive;
- “Attempt to account for all occupants. If the aircraft disintegrated in flight, the wreckage, survivors and casualties may be scattered over a large area;
- “Summon medical assistance if required and verify that this assistance has been sought. Consider shelter for casualties if the accident site poses potential hazards;
- “If you see evidence of a spreading post-accident fire or possible explosion from fuels or armaments, move survivors a safe distance from the scene; [and,]
- “Stay clear from wing-mounted tanks, armor, landing gear struts (oleos) and pressure vessels (gas bottles). These assemblies can explode with devastating violence if disturbed following impact damage and particularly if fire is present.”
Although emergency services take precedence, the guide says, “It is important that wreckage, ground scars and the accident site are disturbed as little as possible. This will ensure that investigators are able to determine the factors that contributed to the accident.”
Once the immediate needs are met, and if accident investigation authorities have not yet arrived, first responders should try to locate witnesses and obtain statements from them. Taking eyewitness statements might seem best left to experienced investigators for later. But, says the guide, “Preliminary eyewitness recollections detailing first reactions can be valuable to investigators. They will normally be untainted by reflection, rumor or exposure to the news media.”
Among the witness recollections sought should be “the position from which the eyewitness observed the event; the time of the accident; weather conditions at the time of the accident; the direction the aircraft was heading and what it appeared to be doing; an estimate of the aircraft’s height, using trees and buildings as a reference where appropriate; if the aircraft was on fire in flight; what sounds were heard; what the impact angle of the aircraft was; if any objects fell from the aircraft before impact, and if so, what the flight path of the aircraft was at the time.”
— Rick Darby
Books
Visualize Safe Flying
Aviation Visual Perception: Research, Misperception and Mishaps
Gibb, Randy; Gray, Rob; Scharff, Lauren. Farnham, Surrey, England and Burlington, Vermont, U.S.: Ashgate, 2010. 311 pp. Figures, tables, references.
“Eyes that have evolved for bipedal hunting and gathering have some catching up to do to handle the three-dimensional variations of manned flight,” says Tony Kern, a retired U.S. Air Force pilot, in the foreword. “Comprehending the complexities and limitations of human vision in aviation is essential to operators of all types of aircraft. In the past, the importance of this subject has been understated, neglected or overlooked altogether by most aviators. …
“Currently, aviators learn to adapt their ground-based vision to the aviation environment through trial and error, using techniques offered by their instructors or shared pilot-to-pilot. Vital topics such as composite crosscheck, see-and-avoid scanning and visual illusions are informally passed along generation to generation, evolving nearly as slowly as we are. It is not that the scientists aren’t doing their jobs; they certainly are. Each year there are dozens of advances made in key areas regarding the human-machine interface. However, up until now you had to comb through dozens of scientific journals to find these studies. Even then, the relevant material was not always user-friendly or easily understood.”
This book is an attempt to rectify the situation. It covers the physiology and psychology of vision in piloting applications, including what Kern calls “the finest compilation and discussion of visual illusions I have ever read, and pilots who internalize this information will be immediately safer.”
— Rick Darby