tell two stories fatigue – definition and effects some operationally significant aspects of...
TRANSCRIPT
• Tell two stories• Fatigue – definition and effects• Some operationally significant aspects of
fatigue• Contribution of fatigue to risk and accidents• Practical countermeasures• CAM initiatives• An outsider’s view of FRMS
• 7 Squadron Chinook squadron operating in Kosovo
• Crew fatigued – 3 to 4 hours sleep per night for several days
• Sleeping in dilapidated buildings
• Mission behind enemy lines, high threat area
• Pilot awoke over sea at 200 feet going down
• Pulled collective up to its limit for first time in pilot’s career
• Near CFIT
Definition:• Subjective feeling of tiredness, lethargy,
lack of motivation• Objective performance decrements
Definition:• Subjective feeling of tiredness, lethargy,
lack of motivation• Objective performance decrements
People are not good at assessing their own performance decrement
Van Dongen et al in Sleep 2003 (from Caldwell)
Performance Deficit
Performance Deficit
Self-Rated SleepinessSelf-Rated Sleepiness
Definition:• Subjective feeling of tiredness, lethargy,
lack of motivation• Objective performance decrements
Caused by:• Sleep loss• Work load• Time of day (circadian rhythm status)
Susceptibility to fatigue varies greatly• Levels of performance deficit can vary
ten fold with equal amounts of sleep deprivation
• Resistant and susceptible people report the same amount of sleepiness
• Need same amount of sleep• A schedule to suit fatigue resistant
people can result in dangerous levels of fatigue in others
Caldwell et al (2005) Behavioral Neuroscience 119 694-707
US Navy recruit training camp•Mean age 18 (17-34)•Eight week course•Intense academic and physical regimen •Traditionally 6 hours sleep per night
J. Lamb PhD, USN Naval Submarine Research Laboratory
• Changed to 8 hours per night in 2002
• Highly significant increase in examination scores
• Attrition halved
• Sick call decreased 70%
J. Lamb PhD, USN Naval Submarine Research Laboratory
• Does resistance to fatigue make selection for senior rank more likely?
• Mood changes: irritability, decreased cooperation
• Unconscious acceptance of lower personal standards
• Decreased ability to sustain attention– Increased errors
• Decreased number of items which a person can keep in mind at one time
• Leading to diminished situational awareness, “tunnel vision”
• Procedural, rule-based activities most resistant to fatigue
• Those requiring creative thinking more vulnerable– Failure to appreciate that the situation is
changing– Difficulty generating new options– Tendency to revert to “tired and true”
solutions not appropriate to current situation
• The wrong question - reactive• The right question - proactive - “What
can we due to reduce the risk of having an accident?”
• Fatigue very often present in military flying– Often contributes to accidents– Rarely a sole cause– Reducing fatigue reduces risk
• 4 of 8 recent rotary accidents – fatigue major contributaaaing factor
• Evaluation of C-17 and Tristar workload revealed significant risk due to fatigue
Jeffrey H. Goode, Journal of Safety Research 2003
Accidents vs Exposure
00.5
11.5
2
2.53
3.54
4.5
1 - 3 4 - 6 7 - 9 10 - 12 > 13
Captain Duty Hours
Acci
dent
Inde
x
Factors increasing mission risk:
Factors increasing mission risk:• Varying skill of the handling pilot• Quality of crew coordination• Pressure: time, demands of “customers”• Nature of landing site: topography,
amount of dust, light, etc• Fatigue• Concern re enemy threats• Many others
“You shall not needlessly fatigue your troops.”
• Failure to appreciate that the situation is changing
“Personally, I think people hear all too often of outstanding leaders such as McChrystal and Petraeus and how they don’t sleep, and it appears to become normalized to work a 16-20 hour day in command during crisis.”
• Caffeine
• Temazepam
• Modafinil
• Much greater awareness of fatigue among leaders
• “Duty Holder” initiative• “It depends on the Captain”
• Planned in-flight napping
• Augmented crews
• Improvements in accommodation, scheduling practices
• Establish an RAF medical officer appointment to provide advice regarding fatigue to military aviators
• Operational Event Analysis – three in progress looking at all human factors aspects of operating specific airframes
• Ongoing collaboration with fatigue authorities at QinetiQ
CAM teaching staff station visits
CAM teaching staff station visits•Coningsby, Leuchars, Odiham, Valley, Yeovilton, Lakenheath
CAM teaching staff station visits•Coningsby, Leuchars, Odiham, Valley, Yeovilton, Lakenheath•In near future Linton-on-Ouse and Brize Norton
CAM teaching staff station visits•Coningsby, Leuchars, Odiham, Valley, Yeovilton, Lakenheath•In near future Linton-on-Ouse and Brize Norton•Visits will continue
Provide presentations regarding fatigue to:• Ab initio, OCU, and refresher students
(RAF, RN)• New military aviation medicine doctors • MAA Flying Supervisors’ Courses and
Flight Safety Officers’ Courses• Ad hoc fatigue presentations to aviators
and maintenance personnel at RAF and RN flying stations – eg Flight Safety Days, RN Senior Officer Symposium
• Fatigue increases risks of mission failure and/or accidents
• Awareness through education can decrease risk
• Local management of fatigue is required
• Consideration of small changes in accommodation, scheduling can greatly reduce fatigue