NASA/TM--2000-209610

Crew Factors in Flight Operations XIII: A Survey

of Fatigue Factors in Corporate/Executive

Aviation Operations

Mark R. Rosekind, Elizabeth L. Co, Kevin B. Gregory, and Donna L. Miller

Alertness Solutions, Inc., Cupertino, California

September 2000
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NASA/TM--2000-209610

Crew Factors in Flight Operations XIII: A Survey

of Fatigue Factors in Corporate/Executive

Aviation Operations

Mark R. Rosekind

Alertness Solutions Inc., Cupertino, California

Elizabeth L. Co

Alertness Solutions Inc., Cupertino, California

Kevin B. Gregory

Alertness Solutions Inc., Cupertino, California

Donna L. Miller

National Aeronautics and

Space Administration

Ames Research Center

Moffett Field, California 94035

September 2000
Available from:

NASA Center for AeroSpacelnformation

7121StandardDrive

Hanover, MD 21076-1320

301-621-0390

National Technical Information Service

5285 Port Royal Road

Springfield, VA 22161

703-605-6000

This report is also available in electronic form at: http//human-factors.arc.nasa.gov/zteam/
1.0 Operational Overview

This report is the thirteenth in a series on

physiological and psychological effects of

flight operations on flight crews, and the

operational significance of these effects.

Corporate/executive flight operations face

unique challenges in the aviation industry.

Most corporate flight crews operate under Part

91 of the Federal Aviation Regulations (FARs),

which does not limit flight or duty periods as

do other Parts that regulate commercial operations. Corporate aviation is often characterized

by unscheduled flights, quickly changing

schedules, time zone changes, and extended

duty days, sometimes with long periods spent

"'on-call." Additionally, corporate pilots'

workload may include non-flight -related

duties such as baggage handling or refueling.

Due to rapid industry growth in recent years,

there are numerous anecdotal reports of

fatigue-related problems experienced by corporate flight crews in both long- and shorthaul operations. However, this is the first scientific examination of fatigue issues in this

operational environment. This study was

designed to identify operationally significant

factors that may influence fatigue, alertness,

and performance in corporate flight

operations.

A survey was developed, consisting of 107

questions in varied format, which targeted six

main areas: demographics, home sleep habits,

flight experience, duty/rest patterns, fatigue,

and the work environment. In collaboration

with the National Business Aircraft Association

(NBAA) and the Flight Safety Foundation,

NASA investigators targeted a representative

sample of corporate/executive operators by

mailing surveys to all U.S.-based member

companies of NBAA that operated business

aircraft at the time. Approximately 11,000

surveys were distributed to 2,100 selected

companies. A cover letter accompanied each

survey explaining the study and emphasizing

that all information provided by subjects was

anonymous and confidential. An enclosed

postage-paid envelope ensured that data were

returned directly to the NASA investigators.

A total of 1,488 corporate flight crewmembers

responded. The sample was 99% male and

averaged 45.2 years of age. Responses from

55 individuals (4%) over age 60, reflect that

Part 91 FARs do not regulate retirement age as

does Part 121. Subjects reported an average of

14.9 yr. of corporate flying and an average

total flight time of 9,750 h.

Describing off-duty sleep at home, the group

reported an average sleep duration of 7 h. 17

min., and 89% characterized themselves as

"good" or "very good" sleepers. More than

half (60%) reported that they snore and about

8% reported having a sleep problem. The most

commonly reported sleep problems were

insomnia, disturbed sleep, and apnea. Only

16% of these problems were diagnosed by a

physician.

Most of the respondents (91%) identified their

flight deck position as captain, and the

group's average salary was $65,500. The

majority (68%) reported flying jet aircraft,

20% turboprops, 7% reciprocating-engine aircraft, and 5% helicopters. Most (82%) indicated that they were required to wear pagers or

were subject to call for duty but reported that

they were rarely "called out" (mean = 1.8

times/mo.). They reported that, within the last

year, they flew an average of 13.8 days/mo.

and logged 35.2 h./mo, of flight time. On

average, they described typical duty days of

9.9 h. that included 3.2 flight segments.

While Part 91 FARs provide minimal guidance

on the issue, many corporate aviation departments set their own flight and duty time limits.

About two-thirds of the respondents reported

having a daily duty time limit, which averaged

14.8 h./day, yet most have no monthly (96%)

or annual (98%) duty limits. Over half (57%)

of the group reported having a daily flight

time limit, which averaged 9.7 h., and again

the majority reported no monthly (89%) or

annual (91%) limits. More than 60% reported
havingapolicy on minimum rest time, which

averaged 9.4 h./24 h.

Almost three-quarters of the group (74%)

described fatigue as a "moderate" or

"serious" concern, and a majority (61%)

characterized it as a common occurrence in

corporate operations. A large majority (85%)

identified fatigue as a "moderate" or

"serious" safety issue, and approach/landing

was the most commonly cited flight phase

affected by fatigue (53%).

Nearly three-quarters (71%) of the pilots

reported that they have "nodded off" during

a flight. Thirty-nine percent reported having

made arrangements for one pilot to nap in the

cockpit seat during flighd. Thirteen percent of

the crewmembers reported that at some time

fatigue had prevented them from flying a

scheduled trip. Fewer than a quarter (21%)

reported that their flight departments offer

training on fatigue issues.

Crewmembers identified factors that influence

fatigue in responses to several questions. In

one question, subjects rated 34 items for their

effects on fatigue level. The highest rated factors, on average, were scheduling issues

(including multiple flight segments, time of

day of operation, late night arrivals, and early

morning departures); operational factors

(including weather, turbulence, and workload);

and sleep loss. Additionally, crewmember

responses to other questions identified long

duty days, short rest periods, extended waits

between flight segments, consecutive duty

days, and crossing time zones as factors that

contributed to fatigue.

Overall, data from this survey indicate that

corporate pilots perceive fatigue as a significant issue in flight operations. These experienced corporate flight crews, who rated themselves as good sleepers at home, identified

specific problems with fatigue in their operational environment. The finding that a vast

1Current FARs do not specifically sanction or prohibit

napping in the cockpit seat.

2

majority of subjects reported "nodding off'

in flight is further evidence of the fatigue

issues facing corporate operations. Yet

according to the pilots, relatively few organizations address these issues through either

comprehensive flight and duty limits or education. More widespread education on alertness management strategies combined with the

application of scientifically-based scheduling

and flight/duty time considerations would provide a strong foundation for an approach

through which corporate flight departments

may address fatigue issues and enhance

corporate aviation safety.

2.0 Introduction

2.1 Fatigue in Corporate/Executive Flight

Operations

Modern commercial aviation requires 24-hour

operations. While sophisticated technology is

utilized in aircraft, air traffic control, maintenance, and other parts of the system, the

human operator remains central to all of these

activities. Therefore, human physiological

capabilities and limitations are critical factors

in maintaining safety and productivity in the

air transport industry.

Corporate/executive flight operations are

defined as the use of aircraft owned or leased

and operated by a corporate or business firm

for the transportation of personnel or cargo in

furtherance of the firm's business, and which

are flown by professional pilots who receive

direct compensation for piloting (ref. 1). Corporate operations encompass a broad range of

activities. An operation may consist of a single

pilot who flies one reciprocating-engine aircraft or an extensive flight department that

manages over 50 aircraft with hundreds of

associated personnel. Duty days can entail several short "hops" or all-night transoceanic

crossings. Flights terminate at small, uncontrolled airstrips, offshore oil platforms, or busy

international airports. Many corporate operations are characterized by a long wait at the

destination, during which business is conducted, followed by a return flight. Other
commonfeaturesareunscheduled flights,

rapidly changing schedules, and extended

duty days. Frequently, corporate pilots have

additional pre- or post-flight responsibilities,

such as baggage handling or refueling.

The primary objective of this study was to

identify operationally significant factors that

may influence fatigue, alertness, and performance in corporate/executive flight operations.

Because corporate operations are so diverse,

they may incorporate many of the challenges

that face other flight environments, including

short-haul, long-haul, overnight cargo,

regional, and rotorcraft operations. Studies of

these other commercial flight operations have

established that crewmembers routinely face

long or irregular duty schedules, rapid multiple time-zone changes, sleep disturbances, circadian disruption, and other challenges unique

to the specific operational demands (ref. 2-6).

These factors can result in fatigue, cumulative

sleep loss, decreased alertness, and degraded

performance. The potential effects on flight

safety and operational effectiveness substantiate fatigue as a safety concern.

Many sources validate this concern. Numerous

studies have shown fatigue-effects in commercial flight crews, including accumulated sleep

loss, alertness and performance decrements,

and unintended episodes of falling asleep

during flight (e.g., refs. 2-8). The NTSB

identified fatigue as a probable cause in an

aircraft accident involving a DC-8 in Guantanamo Bay, Cuba in 1993, and as a contributing factor in the 1997 Korean Air accident

in Guam (refs. 9 and 10). Incidents reported

to the NASA Aviation Safety Reporting System (ASRS), a confidential reporting system

for flight crews and others who operate in the

National Airspace System, have identified

fatigue as a significant safety issue (ref. 11).

Corporate and business aviation operations

have increased steadily since 1992, and projections indicate that they will continue to

grow substantially in the coming years

(refs. 1 and 12). Further, while more corporate

operations are conducted, the National

Airspace System continuously becomes more

crowded and more complex, and business

aircraft performance capabilities improve,

making longer flights possible. As corporate

aviation grows, the industry's concern with

fatigue and alertness issues as they relate to

safety in corporate operations may increase as

well.

Unlike other commercial flight environments

studied, most corporate crews operate under

Part 91 FARs 2. These operators are not regulated by flight time limitations or rest requirements, as are Part 121 and Part 135 operators.

Nevertheless, acknowledging that fatigue plays

a significant role in flight safety, some proactive corporate operators have developed and

adopted their own flight/duty/rest policies.

Anecdotal evidence of this initiative prompted

investigators to examine the extent to which

corporate operators, as a group, have taken

preventive measures against fatigue, and what

remaining areas may benefit from further

action.

2.2 Physiological Background

Fatigue, alertness, and performance are

physiologically determined. A basic understanding of two physiological factors--sleep

and the internal body clock (called the circadian clock)---are necessary background

information. Together, sleep and circadian

rhythms play a fundamental role in determining fatigue and alertness at a given time.

Therefore, factors that affect sleep or the circadian system have the potential to affect

fatigue, alertness, and performance as well.

Sleep is a vital physiological need. Most individuals require about 8 hours of sleep each

day. When a person loses sleep, essentially all

aspects of functioning can suffer, including

alertness, performance, and mood. Sleep loss

can degrade cognitive processes, vigilance,

physical coordination, judgment and decision

making, communication, outlook, and

2Some corporate departments operate under other

FAR Parts, notably Part 135.

3
countless other parameters (refs. 13-14). In

fact, research has demonstrated that 1 hour of

sleep loss can affect waking alertness, and that

2 hours of sleep loss can significantly affect

both alertness and performance (ref. 15).

Sleep loss, over time, accumulates into a sleep

debt, which can exacerbate the effects of acute

sleep loss.

Sleep is a complex process, influenced by

many factors. The quantity and quality of

sleep an individual obtains at a given time

depend on prior sleep and wakefulness, time

of day, age, and environment. Further complicating the matter, these factors interact with

one another.

The basic concept behind the influence of

prior sleep/wake patterns is the following:

when individuals don't sleep, they become

sleepy. That is, a homeostatic drive to sleep

builds from the time of awakening until the

next sleep, just as the drive to eat (hunger)

builds between one meal and the next. The

longer the period of time since sleep, the

stronger the drive to sleep. Conversely, the

homeostatic drive is weaker shortly after sleep.

A very long period of continuous wakefulness

can create an intense sleep drive and associated

sleepiness. When the drive for sleep becomes

strong enough, it can send the brain and body

into spontaneous sleep, regardless of whether

sleep is appropriate or safe under the

circumstances.

Almost every aspect of sleep changes with age.

In general, the quantity and quality of sleep

decrease with age. While older people do not

necessarily need less sleep, they tend to obtain

less sleep at night, have more nocturnal awakenings, truncate sleep in the morning, and nap

more during the day. Therefore, the age of

crewmembers may affect their experience of

fatigue and alertness.

The sleep environment also plays a large role

in the quantity and quality of sleep. Dark,

quiet surroundings and a comfortable temperature and sleep surface are key elements

for a sleep-conducive environment (ref. 16).

Because individual preferences differ widely,

the ability to adjust the environment for comfort is an important consideration.

Even with an ideal sleep environment, sleep

may be difficult due to stress, thoughts, or

worries. Long-haul commercial pilots identified thoughts and worries as one of the top

five items that interfered with their sleep in onboard crew rest facilities (ref. 17).

The ability to sleep also varies with the circadian rhythm of sleepiness. The term "circadian rhythm" (from Latin circa "about"

and dies "day") refers to the cycle of a

physiological function that repeats approximately every 24 hours. Virtually all functions

of the body (e.g., sleep/wake, digestion,

immune function) are controlled by circadian

rhythms, which are regulated by the circadian

clock in the brain. Generally, the body is programmed to sleep at night and to be awake

during the day. Additionally, humans have two

times of maximal sleepiness and two times of

peak alertness each day. At approximately 3-5

a.m. and 3-5 p.m., sleepiness peaks, and sleep

may come more easily. These times correspond to lower levels of alertness and performance. Conversely, at about 9-11 a.m. and

9-11 p.m., alertness and performance peak,

and it may be difficult to obtain sleep, even if

sleep-deprived. Time-of-day fluctuations in

performance have been observed in several

unrelated operational settings (ref. 18).

The circadian system cannot adjust immediately to changes in the work/rest schedule or

time zone. When such changes occur, the circadian system is desynchronized from the

environment for a period of time, and individual rhythms are out of sync with one another.

Circadian disruption caused by irregular

schedules or time zone changes can lead to

sleep loss, performance decrements, worsened

mood, digestive upset, and other symptoms. It

can take from days to weeks for the circadian

clock to resynchronize completely.

4
Clearly, a range of physiological factors can

influence fatigue, alertness, and performance.

While an attempt was made to distinguish

fatigue factors from one another in this study

for the purpose of clarity, they are not completely independent. Further, beyond the intricacies of physiology, the complexity of flight

operations precludes accounting for each difference in circumstance. However, while there

is no simple solution to these issues, by managing fatigue and alertness in corporate flight

operations, the industry takes an important

step in maintaining or improving the safety

margin. Identifying the specific challenges

that face corporate pilots will inform any

efforts to address fatigue in this particular

flight environment.

3.0 Methods

A retrospective survey, comprising 107 questions of varied format, targeted six main topics: demographics (10 questions), home sleep

habits (24), flight experience (28), duty/rest

patterns (19), fatigue during operations (14),

and the work environment (8). The sections on

demographics, home sleep, and flight experience were designed to provide context for

other sections. Pilots who held management

positions completed an additional section of 7

questions. See Appendix A for the complete

survey.

The demographics section included questions

on basic personal information, such as gender,

age, and height. The section on home sleep

habits requested information on a typical

night's sleep at home, including sleep duration, time to fall asleep, and sleep disturbances.

"Flying Information" targeted general flight

experience, such as total flight hours and certification, as well as specific occurrences, such as

flight delays. The duty/rest questions focused

on scheduling practices, including flight times,

duty durations, and augmentation. In the

fatigue section, subjects were asked about their

perceptions of fatigue in corporate operations.

A key question in this section presented subjects with a list of 34 factors, and asked them

to rate each as to the effect it had on

fatigue-level and how frequently they encountered the factor. The section on work environment surveyed the subjects' perceptions

of their flight departments. The additional

section for management pilots focused on the

combination of pilot and management duties.

The survey was field tested by sending 47 surveys to three corporate flight departments.

Crewmembers returned 18 completed surveys

and provided suggestions for improving clarity and relevance. Appropriate changes were

incorporated prior to full distribution of the

survey.

In collaboration with the Flight Safety Foundation and the National Business Aircraft

Association (N'BAA), a representative sample

of the corporate pilot population was targeted

by mailing surveys to all U.S.-based member

companies of the NBAA who operated business aircraft. The number of surveys sent to

each company was determined based on the

number of aircraft operated, using a common

industry estimate (i.e., 3:1 ratio of pilots to

aircraft). This calculation resulted in 10,863

surveys being to sent to 2,100 companies.

Member companies spanned a broad range of

sizes (from single aircraft to extensive departments), aircraft types (from reciprocating

fixed-wing to turbine rotorcraft), and operations (regional to worldwide). Industry members agreed that the NBAA membership

accurately represented the population with

regard to aircraft type, home base time zone,

and flight department size.

Each survey was accompanied by a postagepaid envelope addressed to the NASA investigators and a cover letter signed by them. To

encourage accurate and forthright responses,

the cover letter emphasized that participation

was voluntary, anonymous, and confidential.

Toward that end, pilots were instructed not to

identify themselves and to return surveys

directly to the NASA researchers in the

enclosed envelope.

5
Data were entered into a FileMaker Pro database and then exported onto a DEC systems

Ultrix platform on which the BMDP statistical

software (University of California, Los

Angeles) and S Plus (Statistical Sciences Inc,

Seattle, WA) packages were utilized for data

analysis.

4.0 Results

Corporate crewmembers returned a total of

1,488 completed surveys (a 14% return rate).

Subjects represented flight departments that

employed anywhere from one to 200 pilots,

and worked for companies with one to

675,000 general employees, with an average of

28,200 (N = 1172). According to respondents,

the companies operated an average of 4 aircraft, ranging from 1 to 64. A large majority

of subjects (80%) reported that their companies operated jet aircraft, while under a third

(30%) reported turboprops, 15% reported

rotorcraft, and 13% reciprocating-engine aircraft ("recips"). Of those who reported that

their companies operated jets, the average

number of aircraft per company was 3.1 jets;

those who identified turboprops reported an

average of 2.0 of those aircraft per company;

rotorcraft averaged 3.5 per company, and

recips averaged 1.8 per company. Over two

thirds (68%) of the pilots reported that their

companies flew both domestic and international routes, while almost a third (32%)

reported that their companies flew only North

American routes (see Appendix B for survey

results).

4.1 Demographics

Most (99%) of the crewmembers were male,

and the mean age was 45.2 yr. On average,

subjects were almost 71 in. tall, and weighed

185 lb. The average Body Mass Index (BMI 3)

was 25.9, with 37% of the group falling into

the "ideal" 20-25 range, over half (53%) in

the "overweight" range of 25-30, and 9% in

the "obese" range of >30.

3The BMI is calculated as follows: weight / height2 (kg/

m2).

6

The Eastern time zone was the most frequently

reported home base time zone (48%), and

Central the second (40%). Similarly, 49% of

the group identified the Eastern time zone as

the one in which they lived, and 39% Central.

Subjects reported an average commute time of

33 min. (range = 2 min.-15 h.), and most

(98.5%) reported commuting by automobile,

while only 1% cited airplane commutes.

Fifteen percent of the pilots reported holding

other jobs in addition to their corporate flying

positions, and they spent an average of

57 h./mo, at those jobs.

4.2 Home Sleep

Respondents provided the following information based on an average night of sleep at

home, at ]east 2 days after returning from a

trip. The crewmembers reported an average of

4.2 nights at home between trips. They

reported an average bedtime of 2240 h. when

off-duty, and indicated that it took them 22

min. to fall asleep. Subjects reported awakening an average of 1.5 times during a typical

night at home, and identified the need to use

the bathroom (63%) as the most frequent

cause of awakening, followed by disturbance

from children or spouse (13%), inability to

sleep (10%), and noise (7%). After awakening,

it took them an average of 14 min. to go back

to sleep. On average, subjects reported getting

7 h. 17 min. of sleep and awakening at 0708 h

(7:08 a.m.).

Over half (51%) of the group reported

"never" or "rarely" taking naps, another

30% reported "sometimes" napping, and the

remaining 19% reported napping "often" or

"very often." Those who took naps

(N = 1251) reported an average nap duration

of 49 min.

Sixty percent of the group reported "never"

or "rarely" having problems getting to sleep,

almost a third (32%) reported having problems "sometimes," and 7% reported having

trouble "often" or "very often." The vast

majority of subjects (89%) reported that they

"never" used medications to help them sleep,
andanother8%reportedusingthem

"rarely".Of thosewhodid, overhalf (53%)

indicatedthatthemedicationswere"moderatelyeffective,"whileanother29%reported

thattheywerebetterthanmoderatelyeffective

(N = 147).Themostcommonlyidentified

medications(N = 128)wereover-the-counter

sleepaids(61%of thosewhoreportedusing

medication),andnighttimecoldmedications

(16%),whileonly 1%reportedusingprescription sleepmedication.A largemajorityof

subjects(82%)reported"never"using

alcoholto helpthemsleep.

Overall,mostsubjects(89%) characterized

themselves as "good" or "very good" home

sleepers, while 11% rated themselves "poor"

or "very poor." Over half (60%) reported

that they snore. A significantly higher proportion (67%) of those with BMIs indicating

"overweight" (BMI > 25, N = 916) reported

snoring than those with "normal" BMIs (<

25, N = 561), of whom less than half (47%)

reported snoring (p < .001). Snoring can be

clinically associated with sleep apnea, a relatively common sleep disorder more prevalent

among individuals with higher BMIs.

A great majority (92%) reported having no

sleep problem. Of the small group that indicated a sleep problem, 16% had been diagnosed by a physician. Two individuals (2% of

those who cited a sleep problem) reported that

the sleep problem had never prevented them

from flying a scheduled trip.

Subjects rated 18 factors on how each affected

home sleep, using a scale from 1-"interferes"

to 5-"promotes" (with a middle rating of

3-"no effect"). The factors most often identified as most promoting to sleep (i.e., rated 5)

were pillows (13% of all "promotes"

responses), readiness for sleep (13%), sleep

surface (12%), ventilation (10%), and comfortable clothing (8%). Factors most often

identified as interfering with sleep (i.e., rated

1) were thoughts (19% of all "interferes"

responses), heat (17%), high humidity (15%),

random noise events (9%), and background

lighting (8%). When asked to choose and rank

the top three sleep-promoting factors from the

list of 18, over half of the group (52%)

included "sleep surface" as one of the three,

47% cited "readiness for sleep," and 37%

ranked "pillows." Consistent with these

results, 28% identified "'sleep surface" as the

number one factor, and another 26% rated

"readiness for sleep" first. The same two

factors were most frequently cited as the

second-rated factor, with 15% ranking "sleep

surface" as second and 13% "readiness for

sleep." "Pillows" (22%) was the most

frequently cited third factor.

Subjects rated four additional factors for the

degree to which they interfered with sleep at

home, using a scale of 1-"strongly interferes" to 5-"no effect." "Personal worries"

was cited most as interfering with sleep, with

64% of subjects rating it 1 or 2, followed by

thirst (43%), hunger (27%), and lastly, respiratory factors (20%). Seventy respondents

described other interfering factors, which they

rated as 1 or 2. These were categorized, and

the most common factors were illness (10

responses), family/pets (10), noise (7),

thought/worries about work (6), and

stress/anxiety (6).

4.3 Flight Information

The crewmembers reported having an average

of 5,580 h. of flight time when they were hired

for their current corporate flying positions. At

the time of the survey, they averaged almost

15 yr. (mean = 14.9 yr.) of corporate flying

experience, and 9,750 lifetime hours logged.

Of all certificates and ratings held 4, the majority were for fixed-wing aircraft: Air Transport

Pilot (ATP) represented 35%, followed by

commercial (20%), instrument rating (19%),

and flight instructor certificates (16%). Fewer

respondents held rotorcraft certificates and

ratings, including commercial (4%), instrument rating (3%), ATP (2%), and flight

instructor (1%). On average, pilots categorized

their flight hours as 5,900 h. of corporate

4Many subjects held multiple certificates and ratings.

7
flying, 1,490 h. of military, 2,500 general aviation hours, and about 800 h. in other categories. Most of those who specified another

category (N = 264) indicated hours with a

major, regional, or commuter airline (69%),

followed by charter or air taxi operations

(13%) and air cargo (7%). Per month, the

pilots averaged 39.4 h. of corporate flying, 3.7

h. in general aviation, less than an hour (mean

= 0.6 h.) of military flying, and less than an

hour in other categories.

Pilots reported non-military salaried flying

jobs they have held (N = 1414). Over twothirds of the subjects reported holding other

corporate jobs, (951 responses, 67%). Over

one third (485, 34%) reported having been

employed as flight instructors. Air taxi or

charter flying was cited by 423 pilots (30%),

and airline jobs, including major airlines as

well as regionals and commuters, were

reported by 386 pilots (27%). Seven percent

(105 responses) reported flying cargo. Various other flying positions, including crop

dusting, aircraft testing, surveying, aircraft

demonstration, and law enforcement, were

reported in 108 responses (8%). Subjects

reported having held salaried flying positions

with more than 3 companies on average (mean

= 3.4), and having been with their present

employers for an average of 9.8 yr. at the time

of the survey.

Identifying which type of company aircraft

they operated at the time, a majority (1248,

84%) identified jets, 25% (367) cited turboprops, 9% (137) recips, and 6% (92) rotorcraft. On average, each pilot reported flying

1.2 types of aircraft with their present companies. Most (91%) described their flight deck

position as captain, and the average reported

salary was $65,500. The majority (90%) of

crewmembers reported operating under Part

91 FARs only, some (9%) cited both Parts 91

and 135, and a small number (1%) solely

under Part 135. Very few (< 0.5%) reported

operating under an alternate FAR Part, such as

Part 121 or 125.

A series of 8 questions concerned subjects'

experiences during corporate flight operations

in the year preceding the survey. Each of these

questions had 3 components: The value for a

typical day and a value for each extreme (e.g.,

"typical," "fewest," and "most"), so that

each individual reported a range. The

responses for the "low" extreme were averaged, as were those for the "high" extreme, to

produce the ranges shown below. In a typical

month, crewmembers flew 4.8 h. of "actual

IFR" (i.e., in instrument meteorological conditions, or IMC), with 1.1 h. at the fewest and

10.5 h. at most. A typical flight delay lasted

almost 17 min., with the shortest 4 rain. and

the longest 1 h. 16 min. Pilots reported that air

traffic control (ATC) delays typically occurred

2.4 times/mo., 0.5 times/mo, at least, and 5.5

times/mo, at most. On average, weather delays

occurred 1.4 times during a typical month, 0.2

times in a good month, and 3.7 times during a

month of bad weather. Company-mandated

delays were reported as occurring 2.1

times/mo, typically, 0.6 times/too, at least, and

4.3 times/mo, at most. Mechanical delays

occurred, on average, 0.3 times in a typical

month, 0.1 times/mo, at least, and 1.4

times/mo, at most. Pilots reported flying into a

high density operating area 3.8 times in a

typical week, at least 1.4 times/wk., and at most

8.2 times/wk. Typically, they encountered

non-radar environments 4.4 times/mo., 1.8

times/mo, at the least, and 8.1 times/mo, at

most.

A majority of pilots (82%) reported that they

were required to wear a pager or to be available and subject to call for duty. They related

that, in a typical month, they were subject to

call on almost 16 days (mean = 15.6 "24-h.

periods"). However, they reported actually

being called out only 1.8 times on average,

with 83% of the group called out between zero

and two times in a typical month. When called

out, pilots were typically given 3.7 h. to report

for duty. Asked to compare the time normally

allowed for preflight activities to the time

allowed when called out (N = 846), over half

(57%) described having the "same amount"

8
of time, 30% reported having "somewhat

less" time, and 13% "much less" time.

When pilots were asked about their aspirations

for advancement within the company, the most

frequent response was promotion to management (including chief pilot) or to a higher

management position (526 responses, 38%).

The next most frequent response was "none"

(394 responses, or 28%); some explained that

they had already attained their desired position

and some cited that no advancement was possible or that their retirement was imminent,

while others did not specify a reason. Fifteen

percent (210) expressed the desire to remain

in their current positions, while 9% hoped to

upgrade to more advanced aircraft. Eight percent (116) reported that they planned to retire

soon. Seven percent (99) aspired to make

captain.

Likewise, subjects were asked to identify longterm aviation goals with the following results.

Over one third (481 responses, 34%) indicated

retirement, and over one quarter (365, 26%)

wished to maintain their current positions.

Sixteen percent (230) aspired to management

positions, while 10% aspired to generally

advance within their present company. Nine

percent (125) responded that they wanted safe,

accident-free flying careers or secure jobs

within the industry, and 7% (106) expressed

the desire to simply continue flying. Another

7% (95)wanted to upgrade to more advanced

aircraft. Six percent (80) aspired to flying for

an airline.

4.4 Duty

Subjects were instructed to answer questions in

this section on the flying done for their

corporate aviation job only within the past

year by referencing a logbook or paysheet for

accuracy.

The first 5 questions concerning duty/rest patterns followed the 3-component format

described above (sec. 4.3, fourth paragraph),

requesting values for a typical day and for

each extreme. On average, corporate pilots

reported flying 13.8 duty days in a typical

month, 6.9 days in the slowest month, and

20.1 days in the busiest month. They reported

being scheduled for 33.4 flight hours typically, 14.4 h. at least, and 52.7 h. at most.

Actual flight times averaged 35.2 h./mo, typically, 15.0 h. at least, and 55.5 h. at most.

These flight hours included 3.2 legs on a typical day, 1.2 legs at least, and 7.6 legs at most.

Between flights, crewmembers typically had

7.0 h. on the ground, but ground time ranged

from 2.0 h. to 26.0 h., on average.

A vast majority (96%) of the pilots indicated

that they performed duties in addition to flying. Maintenance, cited by 88% of these

subjects, was the most frequently identified

responsibility, followed by flight planning

(87%), baggage handling (81%), and aircraft

servicing (37%). Additionally, 41% specified

other tasks, the most common of which were

managerial and administrative duties.

Subjects reported starting times of the duty

days in the month leading up to the survey

8

E 6

4

E

i-: 2

0

0000- 0400- 0800- 1200- 1600- 2000-

0359 0759 1159 1559 1959 2359

Time

Figure 1. Duty report times in the month leading up to the survey.

9
(see fig.l). The early morning, from

0400--0759 local time (L), was the most commonly cited, with an average of 7.1 starts during this time period. Next most common was

0800-1159 L, with 5.5 starts on average. An

average of 2.1 duty days started between noon

and 1559 L, and 1.7 periods between 1600

and 1959 L. Relatively few duty periods

started at night, with an average of 0.4 reports

times between 2000-2359 L and 0.3 between

midnight and 0359 L. On average, pilots

reported that 11.1 duty days in a typical

month included fewer than 8 h. of actual flight

time, 3.3 duty days had between 8 and 12 h.

of flight time, and 1.7 duty days required over

12 h. of flight. Pilots reported a typical duty

day of 9.9 h., a shortest duty day of 4.1 h.,

and a longest of 16.0 h. On average, they

described the longest duty day of their

corporate careers as 20.2 h.

Most subjects (93%) reported staying in hotels

during layover rest periods, while 7% reported

staying in crew lounges or other accommodations. In a typical month of duty, subjects who

stayed in hotels during layovers reported

doing so 5.6 times on average, and those who

reported staying in other accommodations

reported doing so an average of 8.5 times. The

most frequently cited alternate accommodations were crew lounges at fixed-based operators (103 responses), followed by companyowned apartments or houses (23) and the

houses of friends or relatives (13). Two-thirds

(67%) conveyed that their operations had a

dispatch or scheduling department.

Over two-thirds of the respondents (68%,

N = 1470) reported that their flight departments set a daily duty time limit, which averaged 14.8 h./day, yet most had no monthly

(96%) or annual (98%) duty limits. Over half

of the group (57%, N = 1462) reported having

a daily flight time limit, which averaged 9.7 h.,

but again the majority reported no monthly

(89%) or annual (91%) limits. Sixty-two percent (N = 1448) reported having a policy on

minimum rest time, which averaged 9.4 h./

10

24 h. Less than half of the group (46%)

reported a minimum rest time between trips,

which averaged 11.2 h. between trips. Almost

a third (32%, N = 1417) reported a limit on

the number of consecutive duty days, which

averaged 7.2 days.

Thirty-five percent of the group reported that

their companies pre-position crews to manage

long-haul requirements. Similarly, 40%

reported that their companies augment flight

crews. Over half (56%) of those who worked

for companies that augment flight crews

reported that the augmenting crewmember is

capable of flying as a captain.

Subjects who reported that their companies

augment crews were asked to describe augmentation policies. Over a third of those who

responded (152, or 35%) indicated that there

was no official policy, that crews were augmented as necessary. Of those who specified a

policy, some described criteria on which augmentation decisions were based, and others

detailed how augmentation was implemented

during operations. The most commonly cited

criterion was a maximum number of duty

hours without augmentation (151 responses, or

66% of those who specified a policy), followed

by a maximum number of flight hours without

augmentation (105, 38%), maximum duty

hours with augmentation (40, 14%), whether

international flying was required (34, 12%),

maximum flight hours with augmentation

(27, 10%), off-duty and rest considerations

(19, 8%), number of flight legs (15, 5%), and

consecutive trips (13, 5%). Those who related

details of implementation cited qualifications

for the augmenting pilot (75 responses, or

27% of those who specified an augmentation

policy), pre-positioning crews (21, 8%), and

rotation of crewmembers (19, 7%).

Distinguishing domestic from international

flights, subjects reported flying 18.5 domestic

flights in a typical month, and 1.0 international flight, on average. These flights represented 35.0 h. of domestic flight and 6.2 h. of
internationalfight permonth.Mostflights

reportedlycrossed3 or fewertimezones

(mean= 14.5flights in a typicalmonth),while

few(0.7flights/mo.)crossedbetween4 and6

timezones,andevenfewer(0.3flights/mo.)

crossedmorethan6 zones.

4.5 Fatigue

Subjectswere askedto describethe work day

during which they had experiencedthe most

fatiguewhile flyingcorporate,and to specify

contributingfactors(N = 1310).These factors

were categorized, and Figure 2 shows the most

frequently cited factors, which included long

duty days (49%), early morning departures

(40%), multiple flight legs (33%), night flying

(26%), weather or turbulence (26%), long

waits (15%), crossing time zones (15%),

workload (15%), consecutive duty days (14%),

and delays (10%).

Almost three quarters of the pilots (74%)

described fatigue in corporate flight operations as a "moderate" or "serious" concern,

and a majority (61%) characterized fatigue as

a common occurrence in corporate flying. A

large majority (85%) expressed the attitude

that, when crew fatigue occurs, it is a "moderate" or "serious" safety concern.

An open-ended question on the ways fatigue

affects flight performance yielded responses

from 1402 subjects, many of whom identified

multiple effects (see fig.3 for the ten most frequently cited). Responses were categorized

into general effects. The most frequently cited

effect was degradation of cognitive abilities,

especially judgment and decision-making, with

526 responses (38%).

Almost a quarter of the respondents (340,

24%) reported slowed reaction times. Over a

fifth (293, 21%) reported decreased alertness,

including loss of situational awareness and

slowed perception. Inability to concentrate was

cited by 247 pilots (18%). Fifteen percent

(215) reported worsened mood, with 157

(11%) specifying apathetic or complacent

attitudes and 69 (5%) reporting irritability.

Errors of omission, especially missed radio

• calls and missed checklist items, were cited by

173 subjects (12%). Degradation of basic

flying skills were reported by 152 pilots

(11%), while sloppiness and the commission of

errors were cited by 132 (9%). Almost 6% (82

responses) reported being tired, sleepy, or

having trouble staying awake. Five percent

(75) reported decreased crew resource management (CRM) and communication skills.

Another five percent (70) responded only that

their performance was degraded, without

elaboration. Sixty-two pilots (4%) reported

No. of

responses

700

600

500

400

300

200

100

m

ii

r

4-

1

m

Long

dut y

day

m

Early

AM

dept

I

.= ! -

Mult. Night Wx/

legs Rt turb

Long TZs Wk- Consec De- No/ Mx No

brks load days lays few prob/ meals

brks fail

Figure 2. Factors contributing to subjects' most fatiguing work days flying corporate operations.

11
physical strain, especially vision problems,

accompanying fatigue. Less than 2% of the

respondents (21 subjects) reported that they

experienced only minor or no effects from

fatigue.

Over half (53% of N = 1342) of the respondents identified approach/landing as the flight

phase most affected by fatigue, while 37%

cited the enroute phase.

An open-ended question asked subjects to

describe strategies that they use to cope with

fatigue before, during, and after trips, and the

responses were categorized. The most frequently reported pre-tfip strategy was sleeping

or napping, identified by 976 respondents

(73% of those who responded to the question).

Healthy diet, a category that included specific

strategies such as eating lightly, was cited in

549 responses (41%). Exercise, which

included staying active, was identified as a pretrip strategy by 375 respondents (28%). Flight

planning activities were cited by 352, or 26%

of respondents. Sixteen percent (218) reported

using caffeine to cope with pre-trip fatigue,

while 139 (10%) attempted to relax or

engaged in recreational activities. Crew

Resource Management (CRM) was emphasized

by 87 pilots (6%) as a strategy during preflight duties. Other coping mechanisms

included staying hydrated (72, 5%), minimizing or avoiding pre-trip alcohol consumption

(65, 5%), and showering or washing face and

hands (62, 5%).

The most frequently reported strategies for

coping with fatigue during flights were moving an d stretching, identified in 494 responses

(37% of those who responded to the question)

(see fig. 4 for the ten most common). Keeping

busy with mental or physical activities, such as

reading or writing, was cited by 481 pilots

(36%). Twenty-eight percent (375) emphasized staying hydrated as a coping mechanism,

and approximately the same number (372,

28%) reported that engaging in conversation

helped them manage fatigue. Over a quarter

cited caffeine use (362, 27%). A fifth of the

respondents (272, 20%) identified strategies

for maintaining safe operations while fatigued,

such as CRM or standard operating procedures

(SOPs). Another frequently identified strategy

was eating, cited by 231 subjects (17%). Napping was reported as an in-flight strategy by

184 pilots (14%). Fresh air, open vents, and

cool temperatures were reported by 179 (14%)

to help cope with fatigue. Other strategies

identified were concentrating (68, 5%), plan

ning for upcoming flight events (51, 4%), and

listening to talk or music on aircraft radios

(38, 3%).

Almost three-quarters of those who identified

post-trip strategies cited sleeping and napping

(873 respondents, 71%). Like the pre-trip

strategies reported, diet (362, 30%) and

exercise (346, 28%) were frequently cited.

Relaxing, which included recreation, was cited

by 337 (28%), followed by leaving the airport

as quickly as possible, which was cited by 150

No. of

responses

600

500

400

300

200

100

m

i

cogn

Rift

Rxn Alerttime ness

i-I f] !-! I-I n n

Concen- Mood Err./ RI Err./ Stay OqM

trat ion Omis. sktls Commis. awake

Figure 3. Effects of fatigue on flight performance.

12
respondents (12%). Seventy-eight pilots (6%)

cited completing various duties, while 61 (5%)

described resuming their normal routines or

adjusting to a new time zone. Fifty-two (4%)

subjects reported showering or washing face

and hands. Almost 4% (46 respondents) identified drinking alcoholic beverages as a posttrip strategy for coping with fatigue.

Twelve hundred fifty-seven pilots made recommendations on how to reduce fatigue in

corporate operations. Most responses (3,042)

were categorized, with the following results

(see fig. 5). Over a third of those who made

recommendations (432 responses, 34%) suggested setting flight/duty/rest time limits-within the company, throughout the

industry, or in the FARs. The second most

common recommendation (423, 34%) was to

improve scheduling, including detailed scheduling suggestions as well as broader scheduling considerations. The third most frequent

suggestion (357, 28%) was to establish minimum rest time, recovery, and days off. Other

common recommendations were shorter duty

days (distinguished from setting duty

limits--252 responses, 20%) and hiring additional crewmembers to relieve the flight load

(192, 15%). According to 138 subjects (11%),

rest facilities at layover locations would help

reduce fatigue. Avoiding early morning

departures or late night flights when possible

was suggested by 134 (11%). The importance

of education was emphasized by 122 subjects

(10%), with 88 (7%) stressing the education of

management and passengers on the effects of

fatigue, while 68 (5%) recommended educating crewmembers. One hundred six pilots

(8%) suggested that fatigue would be reduced

if passengers gave more advanced notice of

departure times and stayed on schedule as

much as possible. Others (94, 7%) recommended avoiding consecutive early or long

duty days, as well as several consecutive days.

Subjects also proposed augmenting crews (85

responses, 7%), maintaining a supportive corporate environment concerning fatigue issues

(82, 6%), replacing crews during long days or

trips (75, 6%), and minimizing peripheral

duties on flight days and days off (72, 6%).

Almost three quarters (71%) of the group

reported having "nodded off" during a

flight. Those who acknowledged that this had

happened more than once (N = 1051)

reported that, in a typical month, it occurred

on an average of 4% of flights. Thirty-nine

percent reported that they had ever been on a

flight where arrangements were made for one

crewmember to nap in the cockpit seat during

the leg. Obviously, aircraft operated by a single pilot clearly do not have this option. For

two-person crews, current FARs neither sanction nor specifically prohibit planned napping

in the cockpit. Those who had made such

arrangements (N = 799) reported that they did

so on 4% of flights in a typical month. Thirteen percent acknowledged that fatigue prevented them from flying a scheduled trip at

some time.

Subjects were asked to rate the extent to which

No. of

responses

500

400

300

200

100

Move Keep

stretch busy

HydrateConvrs Caf f CRy1/ Eat Nap CooI/

SOPS vent

N!

Concent rate

Figure 4. Strategies used by crewmembers to cope with fatigue during flights.

13
34 individual factors affected their fatigue levels on duty on a 4-point scale from "not at

all" to "seriously." Also, they were asked to

rate the frequency with which they experienced each factor on a scale from

"0 = never" to "4 = very often." Responses

from the first part of the question were converted to a numeric scale, assigning a value of

1 to "not at all" and a value of 4 to

"seriously." Mean values were calculated for

each factor. The factors with the top 10 mean

values are shown in figure 6 along with the

frequency rating for each factor.

The factors most frequently rated as "seriously" affecting fatigue (i.e., rated 4) were

similar to those factors with the highest mean

rating. They were: 1) flying 7 or more segments in the same duty day; 2) severe

turbulence; 3) sleep loss; 4) time of day of

operation; and 5) illness. Regarding frequency, flying 7 or more segments in the same

day was reported to occur about a third of the

way between "very rarely" and "sometimes"

(mean = 1.3). Sleep loss was reported to occur

about halfway between "very rarely" and

"sometimes" (mean = 1.5). Severe turbulence

received an average frequency rating of 1.0,

indicating that it occurred "very rarely."

Time of day of operation averaged 2.0, indicating "sometimes.'" Heavy workload was

rated as 1.8 on average, indicating a frequency

close to "sometimes." Illness was reported as

occurring between "never" and "very

rarely" (mean = 0.8).

4.6 Work Environment

Subjects were asked to identify safety issues

emphasized by their flight departments. The

most frequently cited safety issue was Crew

Resource Management (CRM) or crew communication (346 responses, or 26% of subjects

who responded to the question). Fatigue issues,

including duty and rest considerations, were

cited second most frequently, with responses

from 337 subjects (25%). Standardization,

including standard procedures and use of

checklists, was identified by 261 responses

(20%). Maintenance was emphasized in 253

responses (19%), followed by weather factors

(193 responses, 14%) and flight planning (63

responses, 5%). Regulations were cited in 58

responses (4%), while health, including fitness

and nutrition, was identified in 57 responses

(4%). Fifty-seven others (4%) reported that

their flight departments emphasized no safety

issues at all. Others identified Controlled Flight

into Terrain (CFIT--44 responses, 3%), passenger safety and comfort (33, 2%), and

runway length (26, 2%).

Subjects cited various mechanisms for implementing the safety issues identified in the previous question. Training was the most

frequently reported tool of implementation

(674 responses, or 55% of subjects who

responded to the question). Second most

common (337, 28%) was practicing standardization, including standard operating procedures (SOPs), use of checklists, and conducting line checks. Meetings and briefings were

identified in 239 responses (19%), and 158

o_35

E

25

0

Q..

,._15

5

Figure 5. Crewmember recommendations for changes to reduce fatigue in corporate operations.

14
(13%) cited less formal communications, such

as impromptu discussions or electronic mail.

Written materials, such as memos, bulletins, or

publications, were cited in 145 responses

(12%). Scheduling or dispatch departments

were identified as mechanisms for implementing safety issues in 111 responses (9%),

and 75 responses (6%) specifically identified

the setting of flight hours, duty hours, or rest

minimums. Company support, in the form of

open-door policies or supportive corporate

cultures, were identified as a safety mechanism

by 47 respondents (4%).

Pilots compared the safety of their flight

departments to those of major airlines on a

5-point scale from "much less safe" to

"much safer" with a middle rating of "as

safe." Compared to the majors, 64%

considered their operations "somewhat safer"

or "much safer," while another 26%

considered their departments "as safe." Three

quarters of the corporate pilots reported

feeling "secure" or "very secure" about

maintaining their jobs.

Overall, pilots rated their flight department

management highly, with almost two thirds

3.5

moderately

3

2.5

slightly

2

(64%) describing management as "good" or

"very good," while only 16% rated them

"poor" or "very poor."

Over three quarters of the group (79%)

reported that their flight departments did not

offer any training in fatigue issues.

4.7 Management Pilots

Five hundred eighty-seven subjects (about

39% of all subjects) completed some portion

of the section for management pilotsmpilots

who hold both a management position and a

flying position. On average, management

pilots reported spending 48% of their overall

work time on management duties and 53% on

flying. A vast majority (93%) reported that, on

days when they had flying duties, they also

attended to management responsibilities. The

group reported that, on a typical day that

included both management and flying duties,

they spent 72% of the duty day flying and

29% with management duties. On average, a

typical day that included only management

responsibilities lasted 7.0 h., with a shortest

duty day of 3.0 h. and a longest of 10.5 h. In

contrast, for a day that included both types of

duties, management pilots reported a typical

• Effect on fatg

Frequency

2.5

sometimes

2

1.5

not at all

1.5

1

Eff on fat_ Freauencv

no early

_>7 fit sleep sev. time of heavy late nt 4-6 fit hiclh au.to- dae_1 legs loss turb. day wkld arr. legs temp pilot

3.246 2,852 2.800 2.764 2,759 2,745 2.694 2,674 2.534 2,474

1.3 1,5 1.0 2.0 1.8 1.8 2,0 2.1 0.8 2.2

Figure 6. Fatigue factors rated highest by crewmembers.

1 very rarely

g.5

never

g

15
duty day of 10.0 h., a shortest day of 5.0 h.,

and a longest day of 15.0 h.

Describing their specific management duties,

management pilots most frequently identified

responsibilities as chief pilots, supervisors, or

all aspects of management (282 responses,

50% of the 563 subjects who responded).

Scheduling was another commonly cited duty,

with 218 responses (39%). Others reported

having responsibilities in training and CRM

(92, 16%), operations (87, 15%), financial

matters (77, 14%), and personnel issues (50,

9%).

Those management pilots who were involved

in scheduling for their departments were asked

to rank 7 factors with regard to their priority

in scheduling decisions (1 = highest priority).

Responses from 418 subjects conveyed that,

on average, the top consideration was the

pilot's duty time for that work day (mean rank

= 2.2), followed by takeoff times during the

night or early morning (mean rank = 3.8) and

layover rest time (3.9). Availability of equipment ranked 4.0, followed by number of legs

flown by the pilot (4.3), maximizing flight

department cost efficiency (4.4), and time

zones crossed (6.0). Some subjects provided

additional written responses, which were categorized as follows: "other duty factors" (25

responses), such as consecutive duty days;

passenger requirements (15 responses); and

personal considerations (9 responses), such as

vacation time. Collectively, these other factors

received an average rating of 4.0. Responses

were also assessed by calculating the frequency with which each was ranked either 1 or

2. This analysis yielded a different hierarchy

of priorities. Again, pilot's duty time for the

work day appeared to be the first priority, and

was ranked as 1 or 2 by 68% of respondents.

However, the next priority was availability of

equipment, ranked 1 or 2 by 40%. The collection of "other" categories was ranked 1 or 2

by 34%, followed by maximizing flight

department cost efficiency (32%). Takeoff

times during the night or early morning were

ranked 1 or 2 by 24%, layover rest times 21%,

16

and number of legs flown by the pilot 16%.

Time zones crossed was ranked 1 or 2 by less

than 1% of respondents.

4.8 Comparative Analyses

To identify relationships among different

responses, several comparative analyses were

conducted.

An attempt was made to identify relationships

between subjects' assessment of fatigue as a

concern in corporate aviation and various

other factors, such as age, corporate flight

experience, aircraft type, department

flight/duty limits, typical duty duration, and

fatigue training. Only duty duration and fatigue training displayed significant

relationships.

A median split of duty day durations (median

= 10 h.) revealed that those pilots with longer

duty days rated fatigue as a more significant

concern (rating = 3.06) than those with shorter

duty days (2.91) (p < .001). The group with

shorter duty duration (< 10 h.) averaged 7.5 h.

in a typical duty day, while the group with the

longer duty duration (> 10 h.) averaged 11.6

h. Also, significantly more of the subjects with

longer duty days (77%) characterized fatigue

as a "moderate" or "serious" concern than

those with shorter duty days (70%) (p < .01).

Further, post hoc comparisons of duty day

durations of less than 10 h., 10-12 h., 12-14

h., and > 14 h. (with the lower limit included

in the grouping) demonstrated a general trend

that, as duty duration increases, the mean

rating of fatigue as a concern increases. The

group with the shortest typical duty day

(< 10 h.) rated fatigue as a significantly lesser

concern (2.91) than those in the 10-12 h.

group (3.06) and the 12-14 h. group (3.08)

(p < .01), but not the > 14 h. group (3.05),

possibly due to the much smaller group size

and a high level of variability within that

group (see fig. 7).

The median split duty day groups were compared as to their reports of whether they have

nodded off. A significantly higher proportion
(p< .05)of subjectswith longerdutydays

reportednoddingoff (74%)thanthosewith

shorterdutydays(69%).

A significantlysmallerproportionof those

subjectswhoreportedthattheirflight departmentsofferfatiguetraining(51%)characterizedfatigueasacommonoccurrencethan

thosewhoseflight departmentsofferno

fatiguetraining(64%)(p < .001).

5.0 Discussion

5.1 Study Limitations

As with any operational study, certain limitations apply to this investigation. Survey studies, in particular, are limited by the subjective

nature of the data. Responses depend on subjects" perception, memory, and understanding

of the questions. Additionally, subjectivity

plays a well documented role in individuals"

perception of their sleep (ref. 19). Individuals

often make inaccurate estimates of their sleep

latency times, sleep durations, awakenings, and

other parameters. Attempts were made to

quantify response choices to minimize interpretation of descriptors (e.g., "often--l-4

times/wk."). Also, because much of the information requested was retrospective, subjects

were asked to reference their logbooks and

time sheets for accuracy. Nevertheless, interpretation of the findings should allow for the

limitations of subjective data.

The response rate for the survey was relatively

low at 14%. This response rate may reflect that

the survey took approximately 1.5 hours to

complete because of its extensive length (107

questions). While the return rate was low, the

total number of surveys completed and

returned represents a substantial data set (N =

1488).

The survey format also has inherent sampling

limitations due to the fact that voluntary

respondents are a self-selected group. Further,

all respondents worked for companies that

were NBAA members. If crewmembers from

NBAA member companies differ in some

regard from other corporate pilots, then this

sample would not represent accurately the

corporate pilot population. However, both

ek,.

U

to

serious_4

moderate---3

minor--2

--1

not at all--1

< 10 10-12 12-14 _>14

Duty duration (h.)

Figure 7. Ratings of fatigue as a concern in corporate operations grouped by duty duration.

17
industry members and investigators considered

the NBAA sample to represent the population

in most respects.

5.2 Major Findings

The sample of corporate pilots displayed average sleep parameters, including sleep duration

(mean = 7.2 h.), sleep latency (22 min.), few

reported sleep problems, and a high average

rating of their own ability to sleep (89%

"good" or "very good"). Because subjects

presented a normal home sleep profile, their

descriptions of fatigue during operations may

be more likely a result of duty factors rather

than any inherent sleep problems unique to

these subjects.

A primary concern of the study was that of

relevance. Is fatigue a concern in corporate

operations, and if so, to what extent? When

pilots assessed the extent to which fatigue is a

concern in corporate flight operations, almost

three-quarters (74%) rated it a moderate or

serious concern, while another 24% rated it a

minor concern. Only 2% responded that it was

not at all a concern. Likewise, when asked how

significant a safety issue is fatigue when it

occurs, 85% considered it a moderate or serious safety issue, while only 1% considered it

no safety issue. A majority identified fatigue

as a common occurrence in flight operations,

and almost three-quarters of the pilots

acknowledged having nodded off during a

flight.

Data summarized from several questions

examined together portray a common corporate operation: a morning flight to a destination; a relatively long wait while business is

conducted; and a return flight at the end of the

business day. However, while this is a "common" scenario, corporate flight operations are

quite diverse. Survey results indicated that

most duty days began in the morning. Asked

to report duty start times from the month preceding the survey, pilots identified report times

between 0400 and 1159 (early and late

morning) almost three times more frequently

than all other times combined, with the major18

ity of duty days starting between 0400 and

0759. The average typical duty day was

reported to last 9.9 h., and the average typical

ground time between flights was reported as

7.0 h. Pilots also reported that the majority of

their duty days included fewer than 8 h. of

actual flight time, which is the limit set by

FARs for many commercial operations

(although not for Part 91). Given choices of

"< 8 h", "8-12 h," and "> 12 h," pilots

reported that in a typical month, over twothirds of their duty days contained fewer than

8 h. of flight, one-fifth contained between 8

and 12 h., and about one-tenth required more

than 12 h. of flight. No range lower than 8 h.

was offered in the question, and therefore

more specific flight hours per duty day (i.e.,

under 8 h.) cannot be determined from this

question. However, the average number of

actual flight hours in a typical month (35.2 h)

divided by the average number of duty days in

a typical month (13.8 days) suggests a relative

average of 2.6 hours of flight per duty day.

Short flight times combined with long duty

days and long ground times between flights

support the possible model of morning flights

"out" and evening flights "back," with long

waits in between 5.

Fatigue Factors Identified

Responses to questions about subjects' duty

days, their most fatiguing duty day in corporate flying, and how specific factors contributed to fatigue during operations help to identify operationally significant factors that affect

fatigue, alertness, and performance in the

corporate flight environment. Several factors

were cited repeatedly by crewmembers as

contributing to fatigue during operations.

These included various scheduling and

operational factors.

Scheduling Factors

As a general issue, scheduling was identified

by pilots as a fatigue factor in several ways.

5 Clearly, corporate operations do not universally

follow such a pattern, and operational demands vary

considerably among individual flights as well as among

flight departments.
Schedulingfactorsaccountedfor six of theten

mostfrequentlycitedfatiguefactorsin crewmembers'worstcorporateaviationworkdays,

andsevenof thetenmostcommonrecommendationsmadeby crewmembersto reduce

fatigue.Specifically,thesecondmostcommon

suggestionwasto improvescheduling,andthe

ninthmostcommonwasto adhereto the

scheduleasmuchaspossible.Whenratingthe

list of 34itemsfor theircontributionto

fatigue,five of thetenhighestrateditemsconcernedscheduling,and"Companyscheduling

practices,"asanitem,receivedanaverage

ratingof 2.3,whichcorrespondsto between

"slightly" and "moderately"contributingto

fatigue.

Othercommonrecommendationsmadeby

crewmembersto reducefatigueincluded

hiring additionalcrewmembers, augmenting

crews,andswitchingcrews,changeswhich

wouldbroadenschedulingoptionsand

increasethenumberof pilotsavailableto

completea trip.

Specificschedulingissuesidentifiedasfatigue

factorsincludedlongdutydays;earlymorningdepartures,latenightarrivals,andtimeof

dayof operations;rest; multipleflight legs,

longbreaksbetweenflights,andconsecutive

dutydays.Someschedulingissuesmaybe

relatedto operationalrequirements,which

mustbeconsidered.

Long duty days

There is evidence that in many cases long duty

days, rather than many flight hours, may present an elemental challenge to crewmember

alertness. Excessive flight time was not identified by subjects as a major fatigue factor during their most fatiguing corporate work day,

nor did crews report high numbers of flight

hours. In contrast, results from several questions indicated that the pilots did consider duty

time a significant fatigue factor.

Crewmembers reported that their average typical duty days lasted almost 10 h., their longest

duty days were 16 h. on average, and the

longest duty days of their flying careers were

over 20 h. on average. Duty time was highlighted in responses concerning the most

fatiguing corporate duty day, suggestions for

reducing fatigue in corporate operations, and

safety issues emphasized by flight departments. The most common recommendation

for reducing fatigue was to establish

flight/duty/rest requirements (within a company, as an industry, or by regulation). The

results from median splits of duty times and

subsequent post hoc analysis of duty-time

ranges showed significant differences in subjects' assessment of fatigue according to the

length of their duty days. Those with longer

duty days rated fatigue as a more significant

concern in corporate flying than those with

shorter duty days, and a greater number of

those with longer duty days reported having

nodded off during flight.

Long duty days can result in acute or cumulative sleep loss, because they may begin early,

end late, or both. Other factors identified by

subjects, such as multiple flight legs, long

waits, and delays, can contribute to long duty

periods. When experienced consecutively, even

normal duty days can compound the effect

and result in a cumulative sleep debt.

Early report times, late arrival times, and time

of day of operations

The most common time frame for duty report

times according to crewmembers was between

4 a.m. and 7:59 a.m. Early report times were

the second most frequently cited factor in

crewmembers' most fatiguing work days, and

setting later report times was among the most

commonly made recommendation to reduce

fatigue. "Early morning departures" was

among the ten highest rated fatigue factors,

and of those ten, was reported to occur most

frequently (between "sometimes" and

"often").

Early morning departures can lead to sleep

loss by truncating morning sleep. Data from

short-haul commercial pilots indicated that

progressively earlier report times on trip days

19
led to sleep loss (ref. 2). The study suggested

that the pilots could not compensate for earlier

wake times by falling asleep earlier, due to the

natural tendency of the circadian system to

lengthen the body's "day" rather than

shorten it. Likewise, corporate pilots may not

be able to fall asleep earlier to anticipate an

early report time, and therefore may begin

early duty days with a sleep debt.

Likewise, late night arrivals may reduce the

opportunity for sleep and result in sleep loss.

Late night arrivals was the sixth highest rated

fatigue factor, with a rating about threequarters of the way between "slightly" and

"moderately" affecting fatigue. Avoiding late

night arrivals was among the ten most common recommendations by crewmembers to

reduce fatigue.

The time of day of flight operations also was

emphasized as a fatigue factor by pilots. It was

the fourth highest rated factor at 2.8, and night

flights were the fourth most frequently cited

factor in pilots' most fatiguing work day.

Night flights can lead to sleep loss and circadian disruption. A pilot awake, working

through night, will have an acute sleep loss by

not obtaining sleep at the normally programmed circadian time. This work pattern

requires sleep during the day, when the body

is programmed for activity, and will physiologically result in reduced sleep quantity and

quality. Also, simply reversing the sleep/wake

cycle disrupts the circadian system.

Rest

Increasing rest periods or setting minimum

rest requirements constituted the second most

common recommendation to reduce fatigue in

corporate operations. Providing rest facilities

at layover sites was also among the ten most

common suggestions.

Rest considerations are related to, and represent the opposite side of, duty issues. FAR Part

91 does not include minimum rest requirements. Sixty-two percent of crewmembers

reported that their companies had policies on

minimum rest per 24 hours, and fewer than

half reported minimum rest between trips.

The duration and timing of rest periods can

significantly affect the amount of sleep a

crewmember may obtain. "Rest" was not an

item on the list of potential fatigue factors,

however, "sleep loss" was the second highest

rated fatigue factor, with an average rating of

2.9 (almost "moderately" affecting fatigue).

Multiple flight segments

Operational demands often require that trip

sequences include multiple flight legs. Crewmembers reported that typically, they fly 3.2

flight segments per duty day, on average, and

at most they fly 7.6 flight legs, on average.

Flying 7 or more flight segments in the same

day was the highest rated fatigue factor, with

an average rating of 3.2, between "moderately" and "seriously" affecting fatigue.

Flying between 4 and 6 flight segments was

the seventh highest rated factor. When crewmembers identified fatigue factors that contributed to their worst work days, multiple

flight legs was the third most frequently cited

factor. Multiple flight legs also may contribute

to long duty days. Additionally, flying multiple flight legs increases the amount of time

spent in critical, low-altitude phases of flight.

Long breaks between flights

Crewmembers reported that the typical ground

time between flights was 7 h., on average. This

figure is consistent with a model of flying to a

destination, waiting while business is conducted, and then conducting a return flight.

These extended breaks may contribute to long

duty days, and rest may not be possible during

the breaks. Long breaks were the sixth most

frequently cited factor contributing to crewmembers' most fatiguing work days. In recommendations to reduce fatigue in corporate

aviation, providing rest facilities at the layover

destination was the sixth most common suggestion. The predictability of the flight schedule also may affect the ability of crewmembers

to obtain rest during long waits.

20
Consecutive duty days

The effects of long duty days, sleep loss, and

other factors may be compounded by repetition over several days. Less than one-third of

the group reported that their companies limited the number of consecutive duty days

flown. Consecutive days of work were

emphasized as a fatigue factor in

crewmembers' descriptions of their most

fatiguing work day as well as in their

recommendations to reduce fatigue in

corporate operations.

Operational Factors

Corporate/executive aviation has specific

operational requirements in order to provide

service to companies and individuals while

maintaining safety and efficiency. While it is

critical to fulfill the operational needs, identifying and acknowledging fatigue factors may

allow for the development of useful strategies

to reduce their effects.

Workload

The role of workload in fatigue is complex

and not clearly defined. However, anecdotal

evidence and common sense suggest that

higher workloads may contribute to fatigue,

particularly over the course of a long duty

day. It is noteworthy that 96% of all subjects

reported that they had additional duties,

peripheral to their flight duties, including

maintenance, flight planning, baggage

handling, aircraft servicing, and dispatch.

Multiple flight legs also can contribute to high

workload because more time is spent in the

task-intensive flight phases of takeoff, climb,

approach, and landing. Bad weather can

increase workload as well, especially in the

already busy phases of takeoff and

approach/landing. Further, time spent in nonradar environments (reported as occurring 4.4

times in a typical month) can increase the

crew's responsibility for traffic avoidance and

general vigilance.

"Heavy workload" was the fourth highest

rated fatigue factor, with an average rating of

2.8 (more than three-quarters of the way

between "slightly" and "moderately"

fatiguing), and "flying without an autopilot"

was the ninth highest, with a rating of 2.5

(halfway between "slightly" and "moderately" fatiguing). Workload was highlighted

further by crewmember responses concerning

their most fatiguing workdays (the eighth most

commonly cited contributing factor) and by

their recommendations to minimizing extra

(non-flight-related) duties as a way to reduce

fatigue in corporate operations.

Weather and environmental factors

Weather, turbulence, and high temperatures

were identified as fatigue factors in pilots'

responses to several questions. The contribution of these phenomena to fatigue may be

related to workload, physical discomfort, stress,

or other factors. Weather and turbulence

accounted for the fifth most frequently identified contributor to crewmembers' most

fatiguing work days. Severe turbulence and

high ambient temperatures were the third and

eighth highest rated fatigue factors, although it

is noteworthy that severe turbulence was rated

as occurring "very rarely--l-10 times/yr.)."

Flying in actual IFR conditions (i.e., IMC) was

rated 2.3 as a fatigue factor, which corresponds to an assessment between "slightly"

and "moderately" fatiguing. Instrument

weather conditions may further exacerbate

workload when no autopilot is available.

Time Zones

On average, crewmembers reported that typically 2% of flights crossed more than 6 time

zones, 5% crossed between 4 and 6 time zones,

and 93% crossed 3 or fewer time zones.

Crossing time zones was the seventh most

commonly cited factor contributing to pilots'

most fatiguing work days, and "Time-zone

changes" was rated 2.4 as a fatigue factor,

which corresponds to almost half-way between

"slightly" and "moderately" fatiguing.

Crossing multiple time zones can result in

sleep loss and disruption of the circadian system, which can lead to other symptoms of "jet

21
lag," including decreased alertness and

performance.

Effects of Fatigue

Subjects' responses concerning how fatigue

affected pilot performance, what phase of

flight was most affected, the significance of

fatigue as a safety issue, and related questions

indicate some effects of fatigue.

As described previously, 85% of the corporate

pilots expressed the opinion that when crew

fatigue occurs, it is a moderate or serious

safety issue, and over half of the respondents

identified approach-and-landing as the flight

phase most affected by fatigue, given five

choices, and another 5% identified taxi or

takeoff. Low-altitude and terminal operations

such as takeoff and landing are critical, highworkload phases of flight. In 1995, almost half

(49%) of the accidents involving Part 121

operators (including the major airlines), 66%

of those involving Part 135 operators (most

regional airlines), and 61% of accidents

involving Part 91 operators (general aviation,

including corporate/executive, business, and

personal flying) occurred during taxi, takeoff,

approach, or landing (refs. 20 and 21). These

statistics emphasize the vital importance of

peak alertness and performance during lowaltitude and terminal phases of flight.

Specifically, pilots reported that fatigue had

the following affects on their performance:

slowed and degraded cognitive abilities, especially judgment and decision-making; slowed

reaction time; degraded alertness, including

loss of situational awareness; inability to concentrate; worsened mood, including complacency and irritability; errors of omission;

deteriorated flying skills; and increased commission of errors. These reported effects of

fatigue on performance are consistent with

established scientific findings (e.g., refs. 13

and 14).

PilotIndustry Response to Fatigue

With minimal guidance from the FARs on the

issues, some industry members--including

22

individual pilots, entire flight departments, and

industry groups--have developed strategies to

address the challenges of fatigue in corporate

flight operations. At the individual level,

strategies vary greatly, often tailored to the

person's work conditions, physiology, and

lifestyle. At the company level, approaches

include augmentation, pre-positioning, and

developing flight/duty/rest limits and other

standard operating procedures. Industry

groups have organized efforts in areas such as

education, research, and policy

recommendations.

Over a third of the subjects reported that their

companies pre-positioned crews to manage

long-haul requirements, and forty percent

reported that their companies augmented

flight crews. The most frequently reported

criteria for augmentation were: "as necessary" (no official policy), duty-hour limit,

flight-hour limit, international flight, number

of rest hours, number of flight segments, and

consecutive duty days. Crewmembers who

described methods of implementing augmentation cited pilot qualifications, pre-positioning

crews, and rotating crewmembers through

flight deck positions.

Many subjects reported that their flight

departments have developed duty or flight

limitations, or rest requirements. However,

besides daily flight and duty limits, consideration should be given to cumulative effects that

can contribute to fatigue. Therefore, weekly,

monthly, and yearly limits may help reduce

cumulative fatigue, yet fewer than 4% reported

monthly duty limits (11% flight time limits)

and only 2% yearly limits (9% flight time

limits).

Pilots identified personal strategies that they

used to cope with fatigue pre-trip, in-flight,

and post-trip. The most common strategies

identified by pilots emphasized overall health:

sleep, diet, exercise, and hydration. Other

strategies were common techniques for masking fatigue, such as physical movement, caffeine consumption, washing face and hands
withcool water,andengagingin conversation.

Somestrategies,suchaspracticingCRM,

followingSOPs,andextraflight planning,

suggested attempts to compensate for fatigue

with the goal of maximizing flight safety. It is

noteworthy that many crewmembers reported

using alcohol (the most commonly used central nervous system depressant) as a post-trip

strategy to relax or fall asleep. Rather than

enhancing sleep, alcohol can disrupt sleep and

result in the suppression of REM sleep, disrupting both sleep quantity and quality.

Therefore, it is typically not an effective sleep

aid. Interestingly, almost as many pilots

reported avoiding alcohol post-trip as those

who reported using it, which suggests that

some crewmembers may be aware of the

detrimental effects of alcohol on sleep.

Subjects made over 3,000 suggestions for

change to reduce fatigue in corporate operations. These suggestions help identify fatigue

factors and potentially useful recommendations. The most common suggestion was to set

flight/duty/rest limits at some level: within the

company, throughout the industry, or through

regulation. This idea reinforces the identification of duty and rest times as significant factors in fatigue. The second most recommended change was to improve scheduling,

with some subjects suggesting general

improvements while others outlined specific

preferences. Rest and recovery time were

emphasized by many subjects. Others stressed

shorter duty days (without necessarily setting

limits), which re-emphasizes duty time. Hiring

additional crewmembers and procuring rest

facilities at layover destinations were other

common recommendations. Many pilots

expressed that determining departure times

earlier and staying on schedule as much as

possible would enable them to plan their layover time to maximize rest opportunities and

would minimize the stress of an unknown

timetable.

5.3 Recommendations

The demands of corporate flight operations

are varied and complex, as are the physiological requirements of the human body. With one

complex system interacting with another, no

simple answer will exist to fully eliminate

fatigue from the demands of 24-hour global

flight operations. Comprehensive, thoughtful

approaches are crucial to address issues of

fatigue, alertness, and performance in the

industry while providing safe, efficient operations that meet the transportation needs of

companies and individuals. These issues can

be addressed most effectively by applying current scientific knowledge to each facet of

operations, including education and training,

hours-of-service and policy-making, scheduling, alertness strategies, design and technology,

and research (ref. 22).

Education

The coping mechanisms described by subjects

•demonstrate that many in the

industry--individual pilots as well as flight

departments--have already begun to address

fatigue issues. However, while some of those

strategies may be effective (e.g., naps,

caffeine), others may be detrimental (e.g., use

of alcohol as a sleep aid). Successful alertness

management depends on the systematic use of

accurate information.

An integral component of any approach, education can provide scientifically validated

information on which to base personal alertness strategies, flight department policies, and

industry initiatives. Educating corporate passengers and management, in addition to pilots,

is a critical step in developing an approach to

fatigue, and it was among the most frequent

suggestions made by pilots to reduce fatigue

in the industry. The maximum benefit from

education may be gained when it is available

to all industry members, including policymakers, flight department management, dispatchers, schedulers, maintenance technicians,

flight crews, and others. Accurate information

on sleep, circadian factors, how flight operations interact with these physiological factors,

and countermeasure strategies provides an

important foundation for any effective

approach.

23
Flight, Duty, and Rest Guidelines

Flight/duty/rest limitations are other potentially

useful tools. Establishing flight duty limits and

minimum rest requirements was the change

most frequently suggested by subjects to

reduce fatigue. Such limitations can be established in various ways, with different effects:

while some of the pilots suggested regulating

limits, many others recommended setting them

within the company or in the industry, independent of regulation. By proactively setting

industry limits and voluntarily abiding by

them, operators may maintain more flexibility

and control than under a regulated approach.

According to the data, many flight departments have already implemented certain limits.

However, while many subjects reported daily

limits in effect at their companies, these policies, as a group, overlook cumulative flight

and duty time, recovery time, and other

factors. To be effective, flight, duty, and rest

limits should be based on meaningful data

from the operational environment. A comprehensive, scientifically-based approach offers

the greatest benefit.

Toward this end, the Flight Safety Foundation

worked with the NASA Ames Fatigue Countermeasures Program to develop Principles and

Guidelines for Duty and Rest Scheduling in

Corporate and Business Aviation (ref. 23).

This document outlines general scheduling

considerations based on physiological principles, and then provides specific guidelines to

address duty and rest scheduling needs of corporate and business aviation. The document

offers corporate flight departments a way to

proactively address flight/duty/rest issues that

affords valuable operational flexibility.

Scheduling

Several scheduling considerations, including

long duty days, multiple flight segments, sleep

loss, the time of day of the

operation---especially early mornings and late

nights, and consecutive duty days were

repeatedly identified as significant factors in

24

operational fatigue. Additionally, pilots

included in their recommended changes to

reduce fatigue that more predictable scheduling and more adherence to schedules would

help them plan layover time appropriately for

maximum rest.

The fact that several of the primary fatigue

factors identified relate to scheduling suggests

that corporate flight departments may benefit

from re-examining scheduling practices and

incorporate available knowledge concerning

alertness and fatigue. In particular, duty duration, number of flight segments, very early and

very late flight times, consecutive long duty

days, and the setting and adherence to schedules may deserve special attention. Augmentation, additional or pre-positioned crews, and

crew rest facilities (on-board or at destination)

are among the many practices used by corporate flight departments to address their trip

requirements while addressing fatigue. Clearly,

consideration of these factors must be

balanced with operational and economic

demands.

Operations

Operational factors, in many cases, may be

challenging to address because certain operational requirements are either unchangeable

(e.g., time zone changes, weather) or may

involve economic choices.

For example, in several questions, crewmembers identified workload as a fatigue factor,

specifying additional non-flight-related duties

in some cases. Minimizing these peripheral

duties may help to reduce fatigue, yet refueling, baggage handling, maintenance, or other

duties must still be accomplished and may represent economic challenges to a small flight

department. As with other fatigue issues, a balance between safety, operational requirements,

and economic considerations will be critical to

a successful approach.

These recommendations, based on the data

from corporate pilots, address various segments of corporate/executive flight operations,
includingflight crews,flight departmentmanagement,schedulers,andpolicymakers.The

responses from corporate crewmembers reinforce that there are multiple causes of fatigue

in corporate flight operations. Likewise, there

will be no simple solution. A comprehensive

approach that comprises education of operators and flight crews, informed duty policies,

improved scheduling, continuous development

of countermeasure strategies and technology,

and the research necessary to guide and validate these endeavors, will provide maximum

benefit to safety and efficiency in corporate

flight operations.

25
References

1. National Business Aircraft Association.

(1999). 1999 NBAA Business Aviation

Fact Book. Washington, DC: Author.

.

.

.

.

Gander, P. H., Graeber, R. C., Foushee,

H. C., Lauber, J. K., and Connell, L. J.

(1992). Crew Factors in Flight Operations: II. Psychophysiological

Responses to Short-Haul Air Transport

Operations. (NASA TM-88321).

Moffett Field, CA: National Aeronautics

and Space Administration.

Gander, P. H., Graeber, R. C., Connell,

L. J., and Gregory, K. B. (1991). Crew

factors in flight operations: VIII. Factors Influencing Sleep Timing and Subjective Sleep Quality in Commercial

Long-Haul Flight Crews. (NASA

TM-103852). Moffett Field, CA:

National Aeronautics and Space

Administration.

Gander, P.H., Connell, L.J., Gregory,

K.B., Miller, D.L., Rosekind, M.R., and

Graeber, R.C. (1996). Crew Factors in

Flight Operations: VII. Psychophysiological Responses to Overnight Cargo

Operations. (NASA TM-110380).

Moffett Field, CA: National Aeronautics

and Space Administration.

Co, E.L., Gregory, K.B., Johnson, J.M.,

and Rosekind, M.R. (in press). Crew

Factors in Flight Operations XI: A Survey of Fatigue Factors in Regional Airline Operations. (NASA TM-208799).

Moffett Field, CA: National Aeronautics

and Space Administration.

.

.

8.

.

10.

Gander, P.H., Barnes, R.M., Gregory,

K.B., Connell, L.J., Miller, D.L., and

Graeber, R.C. (1994). Crew Factors in

Flight Operations VI: Psychophysiological Responses to Helicopter

Operations. (NASA TM- 108838).

Moffett Field, CA: National Aeronautics

and Space Administration.

Rosekind, M.R., Graeber, R.C., Dinges,

D.F., Connell, L.J., Rountree, M.S.,

Spinweber, C.L., and Gillen, K.A.

(1994). Crew Factors in Flight Operations IX: Effects of Planned Cockpit Rest

on Crew Performance and Alertness in

Long-Haul Operations. NASA TM108839. Moffett Field, CA: National

Aeronautics and Space Administration.

Graeber, R.C. (1986). Crew factors in

flight operations: IV. Sleep and Wakefulness in International Aircrews.

(NASA TM-88231). Moffett Field, CA:

National Aeronautics and Space

Administration.

Rosekind, M. R., Gregory, K. B., Miller,

D. L., Co, E. L., and Lebacquz, J. V..

Aircraft Accident Report: Uncontrolled

Collision with Terrain, American International Airways Flight 808, Douglas

DC-8, N814CK, U.S. Naval Air Station,

Guantanamo Bay, Cuba, August 18,

1993. (No. NTSBtAAR-94/04). Washington, DC: National Transportation

Safety Board, 1994.

National Transportation Safety Board.

(1999). Aircraft Accident Report: Controlled Flight into Terrain, Korean Air

Flight 801, Boeing 747-300, HL7468,

Nimitz Hill, Guam, August 6, 1997. (No.

NTSB/AAR-99/02). Washington, DC"

National Transportation Safety Board.

26
11.

12.

13.

14.

15.

16.

17.

18.

Graeber, R. C. (1988). Aircrew Fatigue

and Circadian Rhythmicity. In E. L.

Weiner and D. C. Nagel (Eds.), Human

Factors in Aviation (pp. 305-344). New

York: Academic Press, Inc.

The CIT Group. (July 1998). Third

Annual Corporate Aircraft Outlook.

Livingston, NJ: Author.

Broughton, R.J. and Ogilvie, R.D. (Eds.).

(1992). Sleep, Arousal, and Performance. Boston: Birkhauser.

Dinges, D.F. and Kribbs, N.B. (1991).

Performing While Sleepy: Effects of

Experimentally-Induced Sleepiness. In

T.H. Monk (Ed.), Sleep, Sleepiness and

Performance, (pp. 97-128). Chichester:

Wiley.

Carskadon, M.A. and Roth, T. (1991).

Sleep Restriction. In T.H. Monk (Ed.),

Sleep, Sleepiness, and Performance (pp.

155-167). Chichester, UK: John Wiley

and Sons, Ltd.

Zarcone, V.P. (1994). Sleep Hygiene. In

M.H. Kryger, T. Roth, and W.C. Dement

(Eds.), Principles and Practice of Sleep

Medicine (2nd Edition) (pp. 542-546).

Philadelphia: W.B. Sauders Co.

Rosekind, M.R., Miller, D.L., Gregory,

K.B., and Dinges, D.F. (1995). Flight

Crew Sleep in Long-Haul Aircraft Bunk

Facilities: Survey Results. Sleep

Research, 24, 112.

Folkard S. and Monk T.H. (1979).

Shiftwork and Performance. Human

Factors, 21:483-492.

19.

20.

21.

22.

23.

Sasaki, M., Kurosaki, Y., Mori, A., and

Endo, S. (1986) Patterns of SleepWakefulness Before and After Transmeridian Flight in Commercial Airline

Pilots. In R.C. Graeber (Ed.) Crew

Factors in Flight Operations: IV. Sleep

and Wakefulness in International Aircrews. (NASA TM-88231). Moffett

Field, CA: National Aeronautics and

Space Administration.

National Transportation Safety Board.

(1998). Annual Review of Aircraft Accident Data: US Air Carrier Operations

(NTSB/ARC-98-0 I). Washington, DC.

(NTIS No. PB98-169147)

National Transportation Safety Board.

(1998). Annual Review of Aircraft Accident Data: US General Aviation

(NTSB/ARG-98-01). Washington, DC.

(NTIS No. PB98-172463)

Rosekind M.R., Gander P.H., Gregory

K.B., Smith R.M., Miller D.L., Oyung

R.L., Webbon L.L., and Johnson J.M.

Managing Fatigue in Operational Settings 2: An Integrated Approach. Journal of Behavioral Medicine,

21:166-170, 1996.

Flight Safety Foundation. Principles and

Guidelines for Duty and Rest Scheduling in Corporate and Business Aviation.

Flight Safety Foundation's Flight Safety

Digest, 16:(2), 1997.

27

Appendix A

Corporate/Executive Operations Survey

Copy of Blank Survey

29

NATIONAL

BUSINESSAmCRAFT

ASSOGIATION, INC.

Corporate/Executive Operations Survey

Fatigue Countermeasures Program

Flight Management and Human Factors Division

NASA Ames Research Center

Moffett Field, CA

31
CORPORATE/EXECUTIVE OPERATIONS SURVEY

NASA is studying fatigue, alertness, and performance issues that affect

flight crews in corporate/executive operations. Please complete this survey and

return it in the enclosed self-addressed, stamped envelope.

DO NOT WRITE YOUR NAME ON THIS SURVEY. This will ensure

anonymity for you and your company. This survey will be administered to

several US corporate flight departments and will be held in the strictest

confidence.

For research purposes only

First, please answer these general questions about your company and flight department:

How many of each type of aircraft

does your company flight department

operate?

recips rotorcraft turbojets turboprops

How many pilots are employed by

your flight department?

pilots employed

Does your company fly strictly

North American domestic routes or a

combination of North American domestic

and international routes? (Check only one.)

In which company division, department,

or structure is your flight department

included?

If, by some chance, you know how many

people are employed by your company

(not just your flight department) please enter

the number in the box.

[] [] []

N. Amer. N. Amer. other (specify)

dom only dora + int'l

total company employees

32
I.

lI.

GENERAL SURVEY DIRECTIONS:

Please answer all questions, and please be as accurate as possible.

is confidential and anonymous.

Please mark boxes and lines as follows:

Small boxes should get a checkmark or an "'x": []

Large boxes should get a number:

Lines should get text:

All information

i_or

kids

HI. Watch for special instructions relating to a question or set of questions.

GENERAL

1. Gender? [] []

male female

2. Age?

3. Weight? lb

4. Height? ft in

5. In what time zone is your home base? [] [3

(Check only one.) Eastern Central

[] [] [] []

Mtn. Pacific Hawaii Alaska

[]

other (GMT)

6. In what time zone do you live? [] [] [] [] [] []

(Check only one.) Eastern Central Mtn. Pacific Hawaii Alaska

[]

other (GMT)

. How long does it usually take you

to travel from your home to your

home base?

hr and min

. What is your usual mode of

transportation from your home

to your home base? (Check only one.)

[] []

auto airplane

[]

other--specify

33
, Do you currently hold another job(s)

in addition to your corporate flying job?

(If "no," skip to #11.)

[]

yes

[]

no

10. How many hours do you spend

at your additional job(s) in a typical

month?

B. SLEEPING AT HOME

Based on an average night of sleep at home (at least 2 days after your return home following a trip), please

give one best answer to each of the following questions. Use your local 24-hour clock.

11. On average, how many nights of sleep

do you get at home between trips?

nights

12. On your days off duty, what time do

you usually go to bed?

I 1

time, 24-hr clock

13. On your days off duty, how long after

going to bed do you usually fall asleep?

hr and __ min

14. When sleeping at home, how many

times on average do you wake up?

__ times

15. If you wake during the night, what [] bathroom [] can't sleep

most often awakens you? [] children/spouse [] noise

(Check ONLY one answer.) [] other

16. If you wake during the night, on

average, how long does it take you to

go back to sleep?

mhr and m min

17. When sleeping at home, what is the

amount of total sleep you get on average?

and min

18. On your days off duty, what time do you

usually get out of bed?

I I

time, 24-hr clock

34
19. How often do you take a nap at

home ?

never

[]

rarely

1-10/yr

[]

sometimes

1-3/mo

[]

often

1-4/wk

[]

very often

5-7/wk

[]

20. On average, how long are your naps? hr and min

21. When sleeping at home, how often do never

you have problems getting to sleep?

[]

rarely

1-10/yr

[]

sometimes

1-3/mo

[]

often

1-4/wk

[]

very often

5-7/wk

[]

22. How often do you take medication to never

help you sleep? (If "never," skip to #25.)

[]

rarely

1-10/yr

[]

sometimes

1-3/mo

[]

often

1-4/wk

[]

very often

5-7/wk

[]

23. If you take medication to help you

sleep, please specify the medication

and dose.

name: dose:

24. Rate the effectiveness of the

medication.

not at all

effective

[] []

moderately

effective

[] []

very

effective

[]

25. How often do you use alcohol to help

you sleep?

never

[]

rarely

1-10/yr

[]

sometimes

1-3/mo

[]

often

1-4/wk

[]

very often

5-7/wk

[]

26. Overall, what kind of sleeper are you? very poor

[]

poor

[]

good

[]

very good

[]

27. Do you snore? yes

[]

no

[]

28. Do you have a sleep problem?

(If "no," skip to #32.)

yes

[]

no

[]

29. What is your sleep problem?

30. Has it been diagnosed by a physician? yes

[]

no

[]

35
31. Has it ever prevented you from flying yes

a scheduled trip? []

no

[]

REMEMBER: Give only one best answer (for each factor) based on an average night of sleep at home

(at least 2 days after you return from a trip).

32. Please rate the following factors and

indicate how much they affect your interferes

sleep. 1 2

a) quality of sleep surface [] []

b) heat [] []

c) cold [] []

d) thoughts running through your head [] []

e) random noise events [] I"]

f) constant background noise [] []

g) background lighting [] []

h) readiness for sleep [] []

i) comfort of clothing [] []

j)low humidity/dry air [] []

k) high humidity [] []

1) trips to bathroom [] []

m) bed partner [] []

n) privacy [] []

o) ventilation [] []

p) sheets [] []

q) blankets [] []

r) pillows [] []

s) other (specify). [] []

no effect promotes

3 4 5

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

33. Please rate the following on the extent

to which they interfere with your

sleep at home.

a) hunger

b) thirst

c) personal worries

d) respiratory factors (i.e., asthma,

allergies, etc.)

e) other (specify).

strongly interferes no effect

1 2 3 4 5

[] [] [] [] []

[] [] [] [] []

[] [] l-I [] []

[] [] [] [] []

[] [] [] [] []

34. From the list in #32, please write the

letters of the top three factors that

promote your sleep at home in

rank order.

.

2.

3.

36
C. FLYING INFORMATION

35. How many total flight hours did you

have when you were hired for your

current corporate flying position?

36. How many total flight hours have you

logged in your lifetime?

I Ihr

37. What certificates/ratings do you

currently hold? (Check all that apply.)

[] commercial (airplane)

[] commercial (rotorcraft)

[] instrument (airplane)

[] other:

[] instrument (rotorcraft)

[] CFI/MEI (airplane)

[] CFI/MEI (rotorcraft)

[] ATP (airplane)

[] ATP (rotorcmft)

38. How many years have you been

flying corporate aviation?

yr

39. How many hours do you have in the

following categories? (All categories

are separate and exclusive.)

corporate military general aviation other--specify:

40. How many hours do you fly in the

following categories in a typical month?

(All categories are separate and exclusive.)

corporate military general aviation other--specify:

41. List all non-military salaried flying jobs

you have had in your aviation career.

(e.g., "capt., regional carder.")

42. With how many different companies

(including your present employer) have

you held a salaried flying position?

__ companies

43. Which company aircraft do you

currently fly? (Check all that apply.)

[] helicopters

[] recips

[] turboprops

[] turbojets

[] other (specify)

37
4. List all company aircraft (make/model)

that you currently fly, and your flight

hours in each.

make and model hours

45. How long have you been employed

by your present company?

[-------_ yr _md _ mo

46. Under which of the following FAR [] Part 135 [] Other (specify)

Part(s) do you currently fly in your job? [] Part 91

(Check all that apply.)

47. What is your annual salary in your

current corporate flying position?

sE I

48. What is your flight deck position?

Capt F/O

[] []

Answer questions 49-61 according to the flying done ONLY for your corporate aviation job within the

past year.

49. How many hours of actual IFR did you

fly in a month (not just filed flight plans,

but IMC)?

typical

[-------_ hr _ hr

fewest most

50. What was the duration of a flight delay? __ min __ min

shortest longest

51. How frequently did ATC delays occur? __ per mo

typical

__ per mo __ per mo

least most

52. How frequently did delays occur due

to weather?

__ per mo

typical

__ per mo __ per mo

least most

53. How frequently did company-mandated

flight delays occur?

__ per mo

typical

__ per mo __ per mo

least most

38
54. How frequently did mechanical delays

occur?

__ per mo

typical least

per mo __ per mo

most

55. How frequently did you fly into a

high density operating area?

__ per wk

typical least

per wk __ per wk

most

56. How frequently did you fly into a

non-radar environment?

__ per mo

typical least

__ per mo per mo

most

57. In your company, can you be required

to wear a beeper (or to be available

through other means) and subject to

call for duty? (If "no," skip to #62.)

yes

[]

no

[]

58. In a typical month, during how many

24-hr periods were you subject to call?

24-hr periods

59. How many times were you actually

called out? (If "0," skip to #62.)

times

60. How much time were you typically given

to report for duty when called out?

hr

61. Compared to the time usually allowed

for preflight activities, how much time

was allowed when you were called out?

[] much less [] somewhat less [] same amount

62. What are your aspirations for

advancement in your current company?

63. What are your long-term aviation

career goals?

39
D. DUTY

Please answer the following questions using your logbook or paysheet, according to the flying done ONLY

for your corporate aviation job within the past year.

64. How many duty days did you fly in __ days __ days __ days

a month? typical fewest most

65. What was your number of scheduled hr

flight hours per month? typical

__ hr hr

fewest most

66. What was your number of actual flight _ hr

hours per month? typical

__ hr _ hr

fewest most

67. How many flight segments did you

fly in a duty day? typical fewest most

68. How much time did you have on

the ground between flights

(time between blocking in and out)?

hr

typical fewest most

hr

69. What duties, if any, do you perform

in addition to your flying duties?

(Please check all that apply, or "none.")

[] maintenance

[] flight planning

[] baggage handling

[] none

[] dispatch

[] safety officer

[] aircraft servicing

[] other

70. During the past month, how many

times did you report for duty during

each of the following time periods?

0000-0359 hr

_-] 0400-0759 hr

------]0800-1159hr

1200-1559hr

1600-1959hr

2000-2359hr

71. In a typical month, on how many

duty days did your actual flying time

fall into each range?

<8 hr 8-12 hr >12 hr

72. What was the duration of your duty day? typical:

shortest:

longest:

-- hr and

__ hr and

hr and

min

min

min

40
73. What was the longest duty day you have

had in your corporate flying career?

_'---] hr and __ rain

74. In a typical month of flying, how many

times did you stay in the following

accommodations during your layover

rest periods?

hotel

__ times times

other: specify

75. Does your operation have a dispatch/

scheduling department?

yes

[]

no

[]

76. What are your flight department's

policies on the following? (Please fill

in values or check "no limit.")

duty time limit:

flight time limit:

minimum rest per 24 hours

minimum time off between trips

maximum consecutive duty days

__ hrperday __ permo

hrperday I .. Ipermo

__ hr per 24-hr period

__ hr between trips

__ consecutive duty days

[] no limit

[] no limit

[] no limit

[] no limit

[] no limit

77. To manage long-haul requirements,

does your company pre-position crews?

yes

[]

no

[]

78. Does your company augment flight

crews? (If "no," skip to #81.)

yes

[]

no

[]

79. What flight deck position is the

augmenting crewmember capable of

holding?

Capt

[]

F/O

[]

80. Describe your company's crew

augmentation policies (e.g., minimum

flight/duty time for augmentation,

in-flight rostering, etc.)

81. In a typical month, how many domestic

and international flights did you fly?

__ domestic flights per mo __ int'l flights per mo

41
82. Theseflights representhowmanyhours

permonthof domesticandinternational

flying?

[---'-'_ hr domestic per mo [----_ hr int'l per mo

83. In a typical month, how many flights

involved time-zone changes of the

following magnitudes?

__ flights __ flights

0--3 zones 4-6 zones

_--_ flights

over 6 zones

FATIGUE

Use the following parameters to describe the sequence of 3 consecutive trips during which you

experienced the most fatigue in corporate flying:

a) Off-duty time prior to trip 1: [-----] # days (24-hr periods)

b) Trip 1: _ # days (24-hr periods) _ cumulative duty time (hr)

total # legs _ cumulative flight time (hr)

c) Off-duty time between trips 1 and 2: _ # days (24-hr periods)

d) Trip 2: _ # days (24-hr periods) _ cumulative duty time (hr)

total # legs _ cumulative flight time (hr>

e) Off-duty time between trips 2 and 3: _ # days (24-hr periods)

f) Trip 3: _ # days (24-hr periods) _ cumulative duty time (hr)

total # legs _ cumulative flight time (hr)

g) Off-duty time before next trip: _--_# days (24-hr periods)

_-'-] # sleep periods

avg. layover duration (hr)

_----'] # sleep periods

avg. layover duration (hr)

F----'-] # sleep periods

_---] avg. layover duration (hr)

---"--] # sleep periods

85. Regarding fatigue, describe the work

day during which you've experienced

the most fatigue while flying corporate,

including the specific factors that made

it difficult.

86. In your opinion, to what extent is

fatigue a concern in corporate flight

operations?

not at all minor moderate serious

[] [] [] []

42
87. Is crew fatigue a common occurrence

in flight operations?

yes

[]

11o

[]

88. When crew fatigue occurs, how

significant a safety issue is it?

not at all

[]

minor

[]

moderate

[]

serious

[]

891 In what ways does fatigue affect

your flight performance?

90. When your flight performance is

affected by fatigue, which phase of

flight performance is most affected?

(Choose only ONE answer.)

[] taxi

[] takeoff

[] enroute

[] descent

[] approach/landing

91. List in rank order three strategies

(for each heading) that you use to

cope with fatigue.

P_TRIP:

1.

2.

3.

/N-FLIGHT:

1.

2.

3.

POSTTRIP:

1.

2.

3.

92. What three changes would you

make to reduce fatigue in corporate

operations? List the most important

first.

.

2.

3.

93. Have you ever "nodded off' during

a flight? (If "no," skip to #95.)

yes

[]

no

[]

43
94. If this has occurred more than once, on

what percentage of flights in a typical

month does it occur?

_----'--] % flights in typical mo

95. Have you ever been on a flight where

arrangements were made for one of

the pilots to nap in their cockpit seat

during the leg? (If "no," skip to #97.)

yes no

[] []

96. In a typical month, on what percentage

of flights does this occur?

__ % flights in typical mo

97. Has fatigue ever prevented you from yes

flying a scheduled trip? []

no

[]

98. For the following question:

1. Check the box that represents the extent to which each factor affects your fatigue level on duty.

2. Then, in the far right column, write the number that corresponds to how frequently you experience

each factor (based on the Frequency Scale below).

3. In the "Comments" section at the end of this question, please elaborate on any factors as needed.

I

Frequency Scale

0=never 1=very rarely 2=sometimes 3=often

(1-10/yr) (l-3/mo) (1-4/wk)

4=very often 1

(5-7____

a)

b)

c)

d)

e)

f)

g)

h)

i)

j)

k)

not at

VFR flight []

IFR flight (actual IMC) []

Light turbulence []

Moderate turbulence []

Severe turbulence []

High ambient temperatures []

Low ambient temperatures []

Icing []

ATC interactions []

Passenger interactions []

Interacting w/other co. employees []

all slightly moderately seriously

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

[] [] []

frequency

44
1)

m)

n)

o)

p)

q)

r)

s)

0

u)

v)

w)

x)

y)

z)

aa)

bb)

cc)

dd)

ee)

ff)

gg)

_i)

not at all

Flying multiple segments

in the same duty day

1-3 []

4-6 []

7 or more []

Time-zone changes []

Flying without an autopilot []

Company scheduling practices []

Time of day of operation []

Early morning departures []

Late night arrivals []

FAR flight/duty/rest limitations []

Sudden scheduling changes []

Heavy workload []

Aircraft vibration when flying []

Unpressurized cockpit []

Noise []

Luggage handling []

Aircraft servicing []

Company mgmt. responsibilities []

Lack of available nutritious food []

Dehydration []

Illness []

Emotional stress []

Sleep loss []

Boredom []

Age []

Other (specify) []

Comments detailing any of the above factors:

slightly

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

moderately

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

seriously

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

[]

(3

[]

[]

[]

[]

[]

f--q

45
F. WORK ENVIRONMENT

99. What safety issues does your flight

department emphasize?

o

2.

3.

100. Through what mechanisms does your

flight department emphasize or implement

these safety issues on the job?

.

2.

3.

101.

much

In your opinion, how safe is your less safe

corporate operation compared to the []

major airlines?

somewhat

less safe

[]

as safe

[]

somewhat

safer

[]

much

safer

[]

102. How do you feel about the long-term

job security in your current position?

very insecure

[]

insecure

[]

scCl.lre

[]

very secure

[]

103. Rate the quality of your flight

department management.

very poor

[]

poor

[]

fair

[]

good

[]

very good

[]

104. Does your flight department offer any

training that addresses fatigue issues?

yes

[]

no

[]

105. If you answered "yes" to the above

question, please elaborate.

106. Please add any comments you

consider relevant to this survey.

107. How long did it take you to complete

this survey (cumulatively)?

(Management pilots: please include the

time it takes you to complete section G.)

arid min

46
G. MANAGEMENT PILOTS

Please answer the following questions ONLY if you hold both a management position and a

flying position in your company.

108. What percentage of your overall work

time do you spend in each role?

% management % flying

109. On days during which you have yes no

flying duties, do you also attend to [] []

management duties?

110. On a typical day during which you have

both management and flying duties, what

percentage of your duty day is spent

in each role?

% management _---] % flying [] not applicable

111. What is the duration of a duty day that

includes ONLY management duties?

__ hr

shortest

hr

longest

112. What is the duration of a duty day that

includes BOTH management and

flying duties?

shortest

hi"

longest

hr

113. In what aspects of management are

you involved?

114. If you are involved in scheduling, please

rank the following categories in the order

of their priority in your company's scheduling

decisions (1 = highest priority).

Please use each # (1 through 8) ONLY once.

__ a) number of legs flown by pilot

__ b) pilot's duty time for the work day

__ c) takeoff times during the night/early morning

__ d) time zones crossed

__ e) layover rest time

__ f) availability of equipment

__ g) maximizing flight department cost efficiency

__ h) other:

47

Appendix B

Corporate/Executive Operations Survey

Survey Results

49

NATIONAL

BUSINESSAIRCRAFT

ASSOCIATION,INC.

Corporate/Executive Operations Survey

Fatigue Countermeasures Program

Flight Management and Human Factors Division

NASA Ames Research Center

Moffett Field, CA

51
CORPORATE/EXECUTIVE OPERATIONS SURVEY

NASA is studying fatigue, alertness, and performance issues that affect

flight crews in corporate/executive operations. Please complete this survey and

return it in the enclosed self-addressed, stamped envelope.

DO NOT WRITE YOUR NAME ON THIS SURVEY. This will ensure

anonymity for you and your company. This survey will be administered to

several US corporate flight departments and will be held in the strictest

confidence.

For re,search purposes only

First, please answer these general questions about your company and flight department:

How many of each type of aircraft

does your company flight department

operate?

13-51

recips rotorcrafi turbojets turboprops

_. I00_

_ 8oI a._

_'_ 60

_ 40 2.0

_ 20 1.8 3.5

F:bcips Rotor T-Jets T-Props

How many pilots are employed by

your flight department?

_ pilots employed

Does your company fly strictly

North American domestic routes or a

combination of North American domestic

and international routes? (Check only one.)

Dom (68%) _ Dom and int'l (32%)

In which company division, deparmaent,

or structure is your flight department

included?

If, by some chance, you know how many

people are employed by your company

(not just your flight department) please enter

the number in the box.

28,200 ] total company employees

52
L

IL

Ill.

GENERAL SURVEY DIRECTIONS:

Please answer all questions, and please be as accurate as possible.

is confidential and anonymous.

Please mark boxes and lines as follows:

Small boxes should get a checkmark or an "x": []

Large boxes should get a number:

Lines should get text:

Watch for special instructions relating to a question or set of questions.

All information

t

kids

A. GENERAL

1. Gender?

female (1%) _t

(_ male (99%)

2. Age? _4-_yr

3. Weight?

4. Height? _-_ft _--] in

5. In what time zone is your home base?

(Check only one.)

Pacific (6%) I_ HI/AK/other (1%)

Mountain (5%) "_j_l_

Central (40%) _ Eastern (48%)

. In what time zone do you live?

(Check only one.)

Pacific (6%) HI/AK/other (1%)

Mountain (5%) _ it

Central (39%) I_) Eastern (49%)

. How long does it usually take you

to travel from your home to your

home base?

_--'] min

. What is your usual mode of

transportation from your home

to your home base? (Check only one.)

plane ( 1%)_tiit_oth e r (<1%)

O auto (9 9%)

53
. Do you currently hold another job(s)

in addition to your corporate flying job?

(If "no," skip to #11.)

yes 15%

no 85%

10. How many hours do you spend [ _'_ [ l_-

at your additional job(s) in a typical

month?

B. SLEEPING AT HOME

Based on an average night of sleep at home (at least 2 days after your return home following a trip), please

give one best answer to each of the following questions. Use your local 24-hour clock.

11. On average, how many nights of sleep _ nights

do you get at home between trips?

12. On your days off duty, what time do

you usually go to bed?

[ 22:40 [

time, 24-hr clock

13. On your days off duty, how long after

going to bed do you usually fall asleep?

21.9 [min

14. When sleeping at home, how many

times on average do you wake up?

[--_ times

15. If you wake during the night, what

most often awakens you?

(Check ONLY one answer.)

noise (7 %). ot her (7 %)

_v

can't sleep (10%)_

children/sp ouse ( 13% ) _ bath room (63 %)

16. If you wake during the night, on [ _J'_ [ min

average, how long does it take you to

go back to sleep?

I-'7"7-'1

17. When sleeping at home, what is the [ /'_ [ hr

amount of total sleep you get on average?

I I

18. On your days off duty, what time do you I 07:08 1

usually get out of bed? time, 24-hr clock

54
19. How often do you take a nap at

home?

20. On average, how long are your naps?

v. often (2%) _ .. ^.,.

often (18%) _ever (11o707

sometimes (30%) _._ rarely (34%)

_4"_ rain

21. When sleeping at home, how often do

you have problems getting to sleep?

v. oft en (<1%)

oft en (7 %) _._never ( 11% )

sometimes (32%) (_ rarely (4 9%)

22. How often do you take medication to

help you sleep? (If "never," skip to #25.)

sometimes (2%) often (1%)

rarely (8°/,) ,_I(_. often (00_0)

k_) never (89 Y.)

23.

24.

If you take medication to help you

sleep, please specify the medication

and dose.

Rate the effectiveness of the

medication.

allergy (2%)

pain (11%) _1,_-melatonin (9%)

Rx (1%)'_'t_l_ nt cold (16%)

OTC sip (61%)'_..J

1-not at all (3%)

5--extremely (16%)___ 2 (16%)

4 (13%) 3-rnoderately (52%)

25. How often do you use alcohol to help

you sleep?

sometimes (5%) -- .often (1%)

"ll_k_v. often (0%)

rarely (11%) )never (83%)

26. Overall, what kind of sleeper are you?

v. poor (1%) _t poor (10%)

v. good (30%) _} good (59%)

27. Do you snore?

no (40)% _ yes (60%)

28. Do you have a sleep problem?

(If "no," skip to #32.)

29. What is your sleep problem?

yes (8%)

no (92%) 0

30. Has it been diagnosed by a physician? yes (16%)

no (84%)

55
31. Has it ever prevented you from flying

a scheduled trip?

yes (1%)

no (99%)

REMEMBER: Give only one best answer (for each factor) based on an average night of sleep at home

(at least 2 days after you return from a trip).

32. Please rate the following factors and

indicate how much they affect your interferes

sleep. 1

no effect promotes

2 } 4

b) heat 506 634 173 122 37

d) thoughts running through your head 563 703 171 33 5

f) constant background noise 180 415 660 139 80

h) readiness for sleep 47 227 295 484 420

j) low humidity/dry air 59 249 604 337 226

1) trips to bathroom 191 639 619 22 4

n) privacy 34 186 634 351 270

p) sheets 8 100 516 598 254

r) pillows 46 174 230 593 431

33. Please rate the following on the extent

to which they interfere with your

sleep at home.

b) thirst

d) respiratory factors (i.e., asthma,

allergies,etc.)

e) other (specify)

strongly inteffe_s no effect

| 2 3 4

126 514 417 265 157

66 217 355 155 656

34. From the list in #32, please write the

letters of the top three factors that

promote your sleep at home in

rank order.

1.

2.

3.

56
C. FLYING INFORMATION

35.

36.

How many total flight hours did you

have when you were hired for your

current corporate flying position?

How many total flight hours have you

logged in your lifetime?

5580 [_

9750 [ hr

37. What certificates/ratings do you

currently hold? (Check all that apply.) 100

80

o 6o

_ 40

_ 20

0

t_

i] ill° , I I I'--II I __I I r--,al

I I I I I I I I

38.

39.

40.

How many years have you been

flying corporate aviation?

How many hours do you have in the

following categories? (All categories

are separate and exclusive.)

How many hours do you fly in the

following categories in a typical month?

(All categories are separate and exclusive.)

14.9 [ yr

159001Fizz] 125001

corporate military general aviation

39.4 [

corporate military

3.7 I

general aviation

other--specify:

other--specify:

41. List all non-military salaried flying jobs

you have had in your aviation career.

(e.g., "capt., regional carrier.")

42. With how many different companies

(including your present employer) have

you held a salaried flying position?

_ companies

43. Which company aircraft do you

currently fly? (Check all that apply.)

o 100 !

75

= 50

¢)

"B 25 90

0

hell

137

I '

recip

367

t -prop

124 5

t-je t

57
4. List all company aircraft (make/model)

that you currently fly, and your flight

hours in each.

make and model hours

45. How long have you been employed

by your present company?

46. Under which of the following FAR

Part(s) do you currently fly in your job?

(Check all that apply.)

Pt 135 only (1%) .... , .

Pt 91 & Pt 135 ._,_.omer _u_o)

-.,t,'lh. (9%)

_t Pt 91 only (90%)

47. What is your annual salary in your $ [ 65,500 ]

current corporate flying position?

48. What is your flight deck position? f/o (9%)

(_ capt (91%)

Answer questions 49-61 according to the flying done ONLY for your corporate aviation job within the

past year.

49. How many hours of actual IFR did you

fly in a month (not just filed flight plans,

but IMC)?

_hr F--i_hr ] 10"5 Ihr

typical fewest most

50. What was the duration of a flight delay'?. [ 16"8 [min _min _min

typical shortest longest

51. How frequently did ATC delays occur? _ per mo _ per mo [--_ per mo

typical least most

52. How frequently did delays occur due

to weather?

per mo _ per mo _ per mo

typical least most

53. How frequently did company-mandated

flight delays occur?

per mo _ per mo _ per mo

typical least most

58
54. How frequently did mechanical delays

occur?

['-_ per mo

typical

0"1 I permo

least

_---] per mo

most

55. How frequently did you fly into a

high density operating area?

_per wk

typical

I 1"4 _perwk

least

56. How frequently did you fly into a

non-radar environment?

[-'_ per mo

typical

_"q per mo

least

_per mo

most

57. In your company, can you be required

to wear a beeper (or to be available

through other means) and subject to

call for duty? (If "no," skip to #62.)

no (18%)(_, yes (82%)

58. In a typical month, during how many

24-hr periods were you subject to call?

[-_ 24-hr periods

59. How many times were you actually

called out? (If "0," skip to #62.)

[--_ times

I-'7"7"-I

60. How muchtime were you typically given I -_-r I mr

to report for duty when called out?

61. Compared to the time usually allowed

for preflight activities, how much time

was allowed when you were called out?

same amt (57%)

much less (13%)

(_ somewhat less (30%)

62. What are your aspirations for

advancement in your current company?

63. What are your long-term aviation

career goals?

59
D. DUTY

Please answer the following questions using your logbook or paysheet, according to the flying done ONLY

for your corporate aviation job within the past year.

64. How many duty days did you fly in

a month?

[-_ days I 6.9 [days [-_ days

typical fewest most

65. What was your number of scheduled

flight hours per month?

_"-] hr I 14"4 [hr _hr

typical fewest most

66. What was your number of actual flight

hours per month?

[35.2 [hr I 15"0 [hr [55.5 [hr

typical fewest most

67. How many flight segments did you

fly in a duty day?

!12 !

typical fewest most

68.

69.

70.

How much time did you have on

the ground between flights

(time between blocking in and out)?

What duties, if any, do you perform

in addition to your flying duties?

(Please check all that apply, or "none.")

During the past month, how many

times did you report for duty during

each of the following time periods?

_"] hr _'_hr _"'_ hr

typical fewest most

14°°Ii- -

1000

600 =

• ;

Mx Fit plan

_'] 0000-0359 hr

['_-] 0400--0759 hr

,I_=_ _

: . ! ! ! ;

Bagg. Disp. Safety Servic. Other

-]o oo_ |_

...._ 1159 hr 1600-1959 hr

2E-l_ 1200--1559 hr _-4-] 2000-2359 hr

71. In a typical month, on how many

duty days did your actual flying time

fall into each range?

72. What was the duration of your duty day?

6O

<8 hr

typical: _9"--_1 -- hr

shortest: V 4-""_ -- hr

longest: F 1_'(- hr

i13.31|

8-12 hr >12 hr
73.

74.

What was the longest duty day you have

had in your corporate flying career?

In a typical month of flying, how many

times did you stay in the following

accommodations during your layover

rest periods?

52 t , j times times

hotel other: specify

crew lounge (7%) jz °ther (2%)

_) hotel (91%)

75. Does your operation have a dispatch/

scheduling department? no (33%) Qyes (67%)

76.

77.

What are your flight department's

policies on the following? (Please fill

in values or check "no limit.")

duty time limit:

flight time limit:

minimum rest per 24 hours

minimum time off between trips

maximum consecutive duty days

To manage long-haul requirements,

does your company pre-position crews?

,4_ ,_r_ar I '4_ I_ormoI 19_0l_ry._no.m.

97 l_p_.day196 lpormo1995I_ryr_no,,mit

9.4 Jl'a" per 24-hr period [] no limit

1 1.2 ] hr between trips [] no limit

7.2 ] consecutive duty days [] no limit

no (65%) _ yes (35%)

78. Does your company augment flight

crews? (If "no," skip to #81 .) no (60%) G yes (40%)

79. What flight deck position is the

augmenting crewmember capable of

holding?

f/o (44%) 0 capt (56%)

80.

81.

Describe your company's crew

augmentation policies (e.g., minimum

flight/duty time for augmentation,

in-flight rostering, etc.)

In a typical month, how many domestic

and intemational flights did you fly?

160

140

120

100

80

60

40

20

0

m

1°/I

{criteria} > {implementaion}

domestic flights per mo _'-] int'l flights per mo

61
82.

83.

These flights represent how many hours

per month of domestic and international

flying?

In a typical month, how many flights

involved time-zone changes of the

following magnitudes?

FATIGUE

"_" ] hr domestic per mo ['-_ hr int'l per mo

[14.5 ]flights _ flights ] 0.3 ]flights

0--3 zones 4-6 zones over 6 zones

4-6 (5%) _1;6 (2%)

0-3 (93%)

Use the following parameters to describe the sequence of 3 consecutive trips during which you

experienced the most fatigue in corporate flying:

a) Off-duty time prior to trip I:

b) Trip 1:

_# days (24-hr periods) [--2"_ # sleep periods

1-'2_ # days (24-hr periods)

_ total # legs

r'_'] cumulative duty time (hr)

_6_'] cumulative flight time (hr)

_avg. layover duration (hr)

c) Off-duty time between trips 1 and 2: _ # days (24-hr periods) _ # sleep periods

d) Trip 2: _"-] # days (24-hr periods)

_ total # legs

e) Off-duty time between trips 2 and 3:

r_] cumulative duty time (hr)

[--_"] cumulative flight time (hr)

avg. layover duration (hr)

f) Trip 3:

_# days (24-hr periods) ["_7 # sleep periods

_'_'-] # days (24-hr periods)

_ total # legs

[-_'_ cumulative duty time (hr)

F-_ cumulative flight time (hr)

_avg. layover duration (hr)

g) Off-duty time before next trip: ["_7 # days (24-hr periods) _ # sleep periods

85. Regarding fatigue, describe the work

day during which you've experienced

the most fatigue while flying corporate,

including the specific factors that made

it difficult.

700

500

,oo,-l lH°t°H0 o° o o .

200 'o_ _ =_" -- --= _ a_ _ _ _ _ _ E

,oo,o=,ll ll, II 'I] I-I II i]:IFi -x°n=z

86. In your opinion, to what extent is

fatigue a concern in corporate flight

operations?

not at all (2%)

serious (27%) [,T_minor (24%)

'lq_Vmoderate (47%)

62
87. Is crew fatigue a common occurrence

in flight operations? no (39%) _ yes (61%)

88. When crew fatigue occurs, how

significant a safety issue is it?

not at all (1%) minor (14%)

/l'x

serious (40%)

moderate (45%)

89. In what ways does fatigue affect

your flight performance?

other (15%)*

can't concentrate (7%)

alertness degraded (15%)

perf degraded (63%)

90.

91.

When your flight performance is

affected by fatigue, which phase of

flight performance is most affected?

(Choose only ONE answer.)

List in rank order three strategies

(for each heading) that you use to

cope with fatigue.

*"other (15%)" factors:

judgement (7%)

omissions (19%) _ apathetic (29%)

irritable (20%) _tired/sleepy (25%)

taxi (2%)

none (10%) _t_T/O (3%)

enroute (34°Y.) app/idg (47%)

""descent (4%)

PRETRIP:

1.

.

.

IN-FLIGHT:

1.

2.

3.

POSTTRIP:

1.

2.

3.

92. What three changes would you

make to reduce fatigue in corporate

operations? List the most important

first.

°

2.

3.

93. Have you ever "nodded off" during

a flight? (If "no," skip to #95.) no (29%) Q yes (71%)

63
94. If this has occun_ more flaan once, on

what l_rcentage of flights in a typical

month does it occur?

_-'_% flights in typical mo

95. Have you ever been on a flight where

arrangements were made for one of

the pilots to nap in their cockpit seat

during the leg.': (If "no," skip to #97.)

no (61%) _i' yes (39%)

96. In a typical month, on what percentage

of flights does this occur?

4.0 [ % flights in typical mo

97. Has fatigue ever prevented you from yes 03%)

flying a scheduled trip? {_

no (87%)

98. For the following question:

1. Check the box that repre._nts the extent to which each factor affects your fatigue level on duty.

2. Then, in the far right column, write the number that corresponds to how frequently you experience

each factor (based on the Frequency Scale below).

3. In the "Comments" section at the end of this question, please elaborate on any factors as needed.

I Frequency Scale

0=never l=very rarely 2=sometimes 3=often

(1-10/yr) (1-3/mo) (1-4/wk) 4=very often 1

(5-7/wk)

not at all slightly moderately seriously frequency

d) Moderate turbulence 315 585 507 30

f) High ambient temperatures 106 441 715 182 I 2"1 I

h) Icing 349 644 371 70

i) _>_ :_i_3

j) Passenger interactions 521 651 240 31

" "!i_.: ." ...., '":,:."•

k) _ w/other co. employees:-_ 666 " 191 20

64
not at all slightly moderately seriously

1) Hying multiple segments

in the same du_ day .................... .

i!!:iiJ_;ii!__ " --: ...... -: ...... -..... : " Z3 •

4-6 77 420 768 143 [2.0[

m) Time-zone changes 168 631 499 129

o 250 634 394 161 [ 1.8 [

_q) 230 511 490 212

s) FAR flight/duty/rest limitations 534 479 237 96

u) workload 104 367 737 229 _

aa

handling 638 628 149 17

Z

515 530 302 56

ee) Emotional stress

gg) Boredom

339 548 422 122

243 645 414 131

ii) Other (specify)

Comments detailing any of the above factors:

65
F. WORK ENVIRONMENT

99. What safety issues does your flight

department emphasize?

°

2.

3.

100. Through what mechanisms does your

flight department emphasize or implement

these safety issues on the job?

l.

2.

3.

101.

102.

In your opinion, how safe is your

corporate operation compared to the

major airlines?

How do you feel about the long-term

job security in your current position?

much less safe (2%) _L s°mewhat less safe

much safer (31%) _ as safe (26%)

somewhat safer (32%)

v. insecure (5°/,)

v. secure (21%) /t_insecure (20%)

secure (54%)

(9*/,)

103.

104.

105.

Rate the quality of your flight

department management.

Does your flight department offer any

training that addresses fatigue issues?

If you answered "yes" to the above

question, please elaborate.

v. poor (7%)

v. good (27%)_1_ p°°r (9%)

good (37%)_ifair (20%)

no (79%) @yes (21%)

106. Please add any comments you

consider relevant to this survey.

107.

66

How long did it take you to complete

this survey (cumulatively)?

(Management pilots: please include the

time it takes you to complete section G.)
G. MANAGEMENT PILOTS

Please answer the following questions ONLY if you hold both a management position and a

flying position in your company.

108. What percentage of your overall work

time do you spend in each role?

48"21% management 52.81% flying

109. On days during which you have

flying duties, do you also attend to

management duties?

110. On a typical day during which you have

both management and flying duties, what

percentage of your duty day is spent

in each role?

_-q% management V_r:-_ % flying [] not applicable

111. What is the duration of a duty day that

includes ON].,Y management duties?

m_hr [-'_ hr ['-_ hr

typical shortest longest

112. What is the duration of a duty day that

includes BOTH management and

flying duties?

_hr [--_ hr [-_hr

typical shortest longest

113. In what aspects of management are

you involved?

114. If you are involved in scheduling, please

rank the following categories in the order

of their priority in your company's scheduling

decisions (1 = highest priority).

Please use each # (1 through 8) ONLY once. Res_tmdents rating the item 1 or 2

2.2 b) pilot's duty time for the work day 68%

6.0 d) time zones crossed

4.0 f) availability of equipment

_g) max_ng _ effx:i_cy

4.0 h) other:

<1%

40%

32%

34%

67
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1. AGENCYUSEONLY(Leaveblank) 2. REPORTDATE 3. REPORTTYPEANDDATESCOVERED

September 2000 Technical Memorandum

4.TITLEAND SUBTITLE 5. FUNDINGNUMBERS

Crew Factors in Flight Operations XIII: A Survey of Fatigue 548-30-32

Factors in Corporate/Executive Aviation Operations

6. AUTHOR(B)

Mark R. Rosekind, Elizabeth L. Co, Kevin B. Gregory and

Donna L. Miller

7 PERFORMINGORGANIZATION NAME(S) ANDADDRESS(ES)

Alertness Solutions, Inc.

Cupertino, California 95014

9.SPONSORING_ONITORINGAGENCYN/_ME(S)ANDADDRESS(ES)

National Aeronautics and Space Administration

8.PERFORMINGORGANIATION

REPORTNUMBER

IH-O06

10.SPONSORING/MONITORING

AGENCYREPORTNUMBER

NAS A/TM--2000-209610

11. SUPPLEMENTARYNOTES

Point of Contact: Melissa Mallis, Ames Research Center, M/S 262-4, Moffett Field, CA 94035

(650) 604-3654

12A.DISTRIBUTION/AVAILABILITY STATEMENT

Subject Category: 52-03 Distribution: Public

Availability: NASA CASI (301) 621-0390

12B.DISTRIBUTIONCODE

13.ABSTRACT(Maximum200 words)

Corporate flight crews face unique challenges including unscheduled flights, quickly changing schedules,

extended duty days, long waits, time zone changes, and peripheral tasks. Most corporate operations are

regulated by Part 91 FARs which set no flight or duty time limits. The objective of this study was to

identify operationally significant factors that may influence fatigue, alertness, and performance in

corporate operations. In collaboration with the National Business Aircraft Association and the Flight

Safety Foundation, NASA developed and distributed a retrospective survey comprising 107 questions

addressing demographics, home sleep habits, flight experience, duty schedules, fatigue during operations,

and work environment. Corporate crewmembers returned 1,488 surveys. Respondents averaged 45.2

years of age, had 14.9 years of corporate flying experience, and 9,750 total flight hours. The majority

(89%) rated themselves as "good" or "very good" sleepers at home. Most (82%) indicated they are

subject to call for duty and described an average duty day of 9.9 h. About two-thirds reported having a

daily duty time limit and over half (57%) reported a daily flight time limit. Nearly three-quarters (71%)

acknowledged having "nodded off' during a flight. Only 21% reported that their flight departments offer

training on fatigue issues. Almost three-quarters (74%) described fatigue as a "moderate" or "serious"

concern, and a majority (61%) characterized it as a common occurrence. Most (85%) identified fatigue as

a "moderate" or "serious" safety issue.

14.SUBJECT TERMS

Fatigue, Sleep, Duty and rest, Scheduling, Corporate aviation, Executive

aviation

17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION

OF REPORT OF THIS PAGE OF ABSTRACT

Unclassified Unclassified Unclassified

15. NUMBER OFPAGES

67

16. PRICECODE A04

20. LIMITATIONOF

ABSTRACT

Unlimited

NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89)

Prescribed by ANSI SId. Z-39°18

298-102