"Effective Crew Scheduling
Strategies on Ultra-long Range
Flights."
John R Fare
Introduction
• Current and Future Demands of our
Customers
– Longer range Aircraft
– Faster Speeds
– Shorter Layovers
Alertness in the Aircraft
• Three Distinct Factors that Determine
Cockpit Alertness
– Circadian Rhythm
– Sleep Propensity/Pressure
– Sleep Inertia
Circadian Rhythm
• Reason
– Regulate bodily functions
• Synchronization
– Length
• 25.3 hours
– Zeitgebers “time keepers”
• 24 hours
– Low
• 0200-0600 and 1500-1700
Circadian Rhythm (cont.)
Circadian Adjustment
• Phase Advance
• Phase Delay
• Resynchronization
Phase Advance
• Occurs when traveling Eastbound
– Day is shortened
• Forced to “advance” to new rhythm
• First sleep is short followed by subsequent
longer rest period
Phase Delay
• Occurs when travelling Westbound
• Day is lengthened
• Initial sleep is longer followed by shorter
sleep episode
Resynchronization
• Asymmetrical Effect
– Difference between Eastbound and Westbound
• Westbound (8 time zones or more)
– 5.1 days for 95% adjustment
• Eastbound (8 time zones or more)
– 6.5 days
• Circadian Synchronization
– Westbound (92 minutes per day)
– Eastbound (57 minutes per day)
Sleep Propensity/Pressure
• Definition
• Adjusting
• Performance Decrements
Sleep Propensity/Pressure
• Definition
– The physiological need to sleep based off of the
last full nights rest
– 16 hours awake/ 8 hours asleep
– Naps improve wakefulness but do not reset
Sleep Propensity’s cumulative effect!
Sleep Propensity/Pressure (cont.)
Adjusting Sleep Propensity
• Lengthening the Sleep/Wake Cycle
– 28 hour day (Westbound travel)
• Greatest need for sleep at 20 hours
• Shortening the Sleep/Wake Cycle
– 20 hour day (Eastbound travel with less than 24
hours of crew rest)
• Greatest need for sleep at 13 hours
Performance Decrements after 16
hours and 24 hours
Sleep Inertia
• Definition
• In-flight Considerations
Sleep Inertia
• Definition
– The grogginess that one feels after waking up
from a deep sleep
Sleep Inertia
• In-flight Considerations
– Short Naps (NASA Naps)
• Less than 40 minutes to stay out of Deep Sleep
• Effective when crew rest time is shorter
– Long Naps
• More beneficial in reducing fatigue levels
• More realistic during circadian low times
• Afford at least 40 minutes of recovery prior to
resuming flight deck duties
Crew Types and Logistics
• Two-Pilot Crew
• Augmented or Three-Pilot Crew
• Crew Change
Two-Pilot Crew
• Duty/Flight Time Limitation Considerations
– Normal
• 14 hours duty/ 12 hours of flight (FSF, 1997)
– Circadian Low *Is flight flying through or landing between the
hours of 0200 - 0600 body adjusted time or duty day starts at 0400 or earlier
• 12 hours duty/ 10 hours of flight and consider
max amount of landings (FSF, 1997)
Augmented Crews
• Definition
• Crew Bunk Categories and Considerations
• Circadian and Sleep Propensity
Considerations
Augmented Crews
• Three Pilots
– From original point of departure?
– From intermediate and or tech stop?
– Supine rest available in a separated area?
• 20 hours of duty (FSF, 1997)
– No supine
• 18 hours of duty (FSF, 1997)
Crew Bunk Categories
• Class I
– 75% sleep opportunity credit (George, 2011)
• Class II*
– 56% sleep opportunity credit (George, 2011)
• Class III
– 25% sleep opportunity credit (George, 2011)
*Business Jet with separated crew rest facilities
Crew Change
• Logistics
• Circadian Considerations
Crew Change Logistics
• Location!
– Available Resources i.e. pilots?
– Great Circle?
– Airline Service for preposition?
– Cost?
– Time to get there?
– Weather?
– Handling?
Fatigue Study
•
•
•
•
•
•
•
Overview
Assumptions
Limitations
Methodology
Treatment of Data
Results
Conclusion
Overview
• Background
– Fatigue Management Program for our SMS
– Justify or refute our current policies
• Geographic Representation
– Europe, Asia, South America
• Participants
– Pilots and Flight Engineers
Hypothesis
• Three-Pilot Crews are less tired than TwoPilot Crews during the last two hours of a
flight to include top-of-descent, approach,
landing, and post-flight
Assumptions
• All participants were operating during or
through their circadian low
• All pilots afforded supine rest
• Two-Pilot Crews
– Two pilots and one Flight Engineer
– Flight Engineer data from augmented flights
considered two-pilot crew
• Three-Pilot Crews
– Three pilots from original point of departure
Limitations
• Human Factors
– Health, emotional stability, family life, quality
of sleep, alcohol/substance abuse
• Meteorological
– Day, Night
• In-flight Conditions
– Turbulence, Convective Weather
Methodology
Stanford Sleepiness Scale (SSS)
Treatment of Data
• All Duty Start Times Adjusted to “Body
Adjusted Time”
– Eastbound
• 57 minutes per day
– Westbound
• 90 minutes per day
Results
• SSS Mean for the Last Two Hours of Duty
• Crewing Technique vs. SSS
• SSS Mean for Entire Flight vs. Start Time of
Duty Day
• Crew Rest Sleep Percentages vs. Duty Hour
SSS Mean for the Last Two Hours of
Duty
SSS During Last 2 Hours of Duty
2.45
2.4
2.35
2.3
Hour 1
2.25
Hour2
2.2
2.15
2.1
2.05
2 Pilot
3 Pilot
Conclusion
• Three-Pilot Flight Crews are Less Tired than
Two-Pilot Crews
Crewing Technique vs. SSS
Crewing Technique vs. SSS
4
3.5
3
2.5
2 Pilot
2
3 Pilot
1.5
1
0.5
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Conclusion
• SSS Levels Separate at Duty Hour 11/ Flight
Hour 9
• Johnson & Johnson Aviation Lowered its
Circadian Low Duty Limits to 9 Hours of
Flight with a Max of 2 Landings
SSS Mean for Entire Flight vs. Start
Time of Duty Day
SSS vs. Adjusted Start of Duty Day
3
2.5
2
1.5
SSS
1
0.5
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
22
23
24
Conclusion
• Start time does correlate to SSS levels of
augmented crews
• There is a significant increase in SSS with
start times between 1800 and 0700
Crew Rest Sleep Percentages vs.
Duty Hour
120
100
80
Sleep
60
Awake
40
20
0
1
2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
Conclusions
• Physiological need determines success
• Most sleep attained between duty hour 9
and 18
• Strategic “rostering”
– PF gets the most consideration
Practical Approaches
• Two Pilots
– KTEB – LFPB – KTEB
– Minimum Layover
– Off Duty Prior to Circadian Low
• Three Pilots
– KTEB – RJTT
– Fuel Stop in PANC
Europe “Quickturn”
• Two Pilots
– Depart KTEB @ 1800 Local
– Arrive LFPB @ 0630 Local
• 10 hour rest period + 2 hours for travel
and “unwinding”
– Depart LFPB @ 1830 Local
– Arrive KTEB @ 2030 Local
Three Pilots to Tokyo
• Three Pilots
– Depart KTEB @ 0800 Local
– Arrive RJTT @ 1300 Local the next day
Summary
• Three-pilot crews are less tired than twopilot crews on extended circadian low
flights!
• Sleep propensity needs to be considered
when augmenting
• Have a plan!
– Rostering
– In-flight fatigue countermeasures
• Learn from your Experiences
References
Billiard, M, & Kent, A. (2003). Sleep: physiology, investigations, and medicine. New York,
NY: Kluwer Academic/Plenum
Caldwell, John A., & Caldwell, J. Lynn (2003). Fatigue in Aviation: A Guide to
Staying Awake at the Stick. Burlington, VT: Ashgate Publishing Limited
CEriksen, C.A., Torbjorn, E., & Nilsson, J.P. (2006). Fatigue in trans-atlantic airline operations:
Diaries and actigraphy for two- vs. three-pilot crews. Aviation, Space, and Environmental
Medicine, 77(6), 605-612.
Gander, P.H., Gregory, B.S., Miller, D.L., Graebner, R.C., Connell, L.J., & Rosekind, R. (1998).
Flight crew fatigue V: Long-haul air transport operations. Aviation, Space, and Environmental
Medicine, 69(9), B37-B48
Gander, P.H., Rosekind, M.R., & Gregory, K.B. (1998). Flight crew fatigue VI: A synthesis. Aviation,
Space, and Environmental Medicine, 69(9), B49-B60.
George, F. (2011, February). Fatigue risk management. Business & Commercial Aviation, 32-37.
Miller, J. C. (2005, May). Operational Risk Management of Fatigue Effects
(AFRL-HE-BR-TR-2005-0073). : United State Air Force Research Lab.
Neri, D., Oyung, R., Colletti, L., Mallis, M., Tam, D., & Dinges, D. (2002), Controlled Breaks as
a Fatigue Countermeasure on the Flight Deck. Aviation, Space, and Environmental Medicine, 73(7)
United Kingdom Civil Aviation Authority (CAA), Safety Regulation Group. (2007). Aircrew fatigue:
A review of research undertaken on behalf of the UK Civil Aviation Authority
(CAA PAPER 2005/04). Retrieved from http://www.caa.co.uk