lecture 9: human factors Flashcards
The Transportation Safety Board of Canada (TSB) is what kind of agency and. reports to who?
An independent agency that reports to Parliament through the President
of the King’s Privy Council for Canada
tsb was created by what?
Created by an Act of Parliament (the Canadian Transportation Accident
Investigation and Safety Board Act) on 29 March 1990.
tsb investigates what?
investigates Air, Maritime, Rail and Pipeline occurrences.
TSB Overview
tsb mandate
to advance safety in air, marine, pipeline, and rail transportation by:
- Conducting independent investigations, including public inquiries when
necessary, into selected transportation occurrences, in order to make
findings regarding their causes and contributing factors; - Identifying safety deficiencies, as evidenced by transportation
occurrences; - Making recommendations designed to eliminate or reduce such safety
deficiencies; - Reporting publicly on our investigations and findings in relation thereto.
Where does HF fit TSB
how many people in tsb
220
What is Human Factors- explain Procrustes (Greek myth
Procrustes had a stronghold between Athens
and Eleusis. In it, he had a bed. He would invite
people to spend the night in his bed. If people
were too tall, he would amputate their legs to
make the fit. If people were too short, he would
stretch them on a rack to make them fit
What is Human Factors
Ergonomics (or human factors) is the scientific discipline concerned
with the understanding of interactions among humans and other
elements of a system, and the profession that applies theory,
principles, data and methods to design to optimize human well-being
and overall system performance.
What is Human Factors?
An applied science focused on understanding human capabilities, and designing systems,
tools and organizations to optimize these capabilities.
* Multiple names: Human Factors, Ergonomics, Human Factors Engineering, Industrial
Psychology…
* Multi-disciplinary covering:
* physiology,
* psychology,
* biomechanics,
* engineering,
* organizational psychology,
* education and training
* more…
realization of this event was..?
Realization that supplemental
oxygen was necessary for high
altitude flight.
Eastern Airlines Flight 401 (1972)
prompted what?
Crash occurred because flight crew were
pre-occupied with a burnt-out landing gear
indicator light.
This and other accidents
prompted Crew Resource
Management training.
History of Human Factors in
Transport Canada’s “Dirty Dozen
name 6
Communication
* Complacency
* Lack of
Knowledge
* Distraction
* Teamwork
* Fatigue
* Lack of Resources
* Pressure
* Assertiveness
* Stress
* Lack of Awareness
* Norms
The Dirty Dozen
Modern Aviation Safety Science
- Moved away from trying to correct human error (the what).
- More concerned with trying to determine the conditions that set up the
error (the why) - Focusing on emergent system risks and safety.
SHEL(L) Model of Human
Factors
A “system view” of human
error.
Espoused that the human is
never the single cause of the
error.
software (procedures, symbology)
hardware (machine)
environment
liveware (human)
match or mismatch of blocks (interface) is just as important of the characteristics of the blocks themsleves,
see slide 31
see slide 32 and 33 and 34
The Bell Curve
Defines every aspect of human existence:
- Anthropometrics
- Intelligence
- Cognition
- Behaviour
- Visual Accuity
- Emotional Intelligence
- Grip strength
- 100 m sprint time
- Ability to hold breath underwater
- Love of Rap Music
- Capsaicin tolerance
- Mate gender selection
- Reading Speed
- …
The Brain: Perception, Cognition and
Decision Making
- Brain is most complex organ in our body.
- Responsible for memories, sensations,
motor control, information processing - Takes in sensory perceptions, processes
these, generates a mental model - Processing “Short cuts” everywhere!
Perceptions and Illusions
Coriolis Illusions (sensation of turning)
Somatogravic Illusions (pilot thinks hes going up, he actually not, in result he may react to make the plane go down)
Linear Vection Illusions (watching a train move while yours is at rest)
auditory illusions
Biases and Heuristics
Bias = a systematic pattern of rationality resulting in a “subjective reality”.
Heuristic = a mental shortcut or “rule of thumb” to arrive quickly at a
decision.
Biases and Heuristics
Availability Bias
Availability Bias = making decisions only on information that immediately
comes to mind on a topic.
Example: Believing airplanes are
unsafe because of highly publicized
plane crashes.
Biases and Heuristics
Confirmation Bias = looking only for information that confirms an already
formed mental model.
Example: VFR Flight Into IFR Conditions
Biases and Heuristics
Hindsight Bias .
Hindsight Bias = a tendency to overestimate the ability to predict an
outcome, once the outcome has happened.
Example: Identifying causal factors before an investigation is complete.
environmental factors
thermal regulation
whole body vibration
noise
G-Induced Loss of Consciousness
Hypoxia
Biases and Heuristics
Halo Effect
Halo Effect = is the cognitive bias where people seen as knowledgeable or
highly respected in a given area are given deference.
Example: Tenerife - FO and flight engineer with senior Capt.
whole body vibration
Largely a helicopter issue.
Can generate discomfort,
nausea and fatigue.
Made worse by
equipment.
Long term exposure can
ground pilots.
noise
From Canada’s Aviation Occupational Health and Safety Regulations SOR/2011-87:
Limits of Exposure
2.4 No employee shall, in any 24-hour period, be exposed to
(a) an A-weighted sound pressure level set out in column 1 of the schedule to this Part for a duration of exposure
exceeding the applicable duration set out in column 2; or
(b) a noise exposure level (Lex,8) that exceeds 87 dBA.
Protection is typically provided by aviation headsets or ear plugs.
G-Induced Loss of Consciousness
High acceleration causes reduced
blood pressure at the brain,
resulting in loss of consciousness.
* G-LOC typically occurs at 4 G or
higher, but depending on history
can occur lower.
* Equipment and AGSM prevents.
Hypoxia
As aircraft ascends, partial pressure of
oxygen decreases.
Cabin altitude of most airliners is 7,000
feet.
10,000 feet and over, supplemental
oxygen is required.
control expectations
Expectation of how
controls work.
Realm of Human Factors
Engineering.
Influenced by Culture
equipment factors
Control Expectations
Human-computer Interaction
American Airlines Flight 965 (1995)
- Aircraft crashed into a mountain Buga,
Columbia. - Pilots had accidently cleared programmed
approach waypoints from FMS. - Resulted in requirement for terrain
awareness warning systems.
Equipment issue accident from
Maintenance.
Runway Overrun, PenAir flight
3296 (from NTSB report).
Immediate cause, improperly
wired antiskid system resulted in
tire failure and loss of braking
ability (among other factors)
task factors
Crew Resource Management
Crew Resource Management
Aviation crew members need to
function as a team
CRM helps crew members
communicate better.
Represented through extensive training
programs.
