Ch 15 - Human Error And Decision Making Flashcards
Errors
A mismatch between the pilots intention and the result - usually from low levels of optimum performance
Usually occur in simple repetitive tasks; 1:100 but can be improved through good training to 1:1000
Computer error 1:10Million (automation)
Humans a fallible to errors - make them very easily
2 Types of Error
1 - Action Slip where the result does not satisfy the intention but the intention was correct
2 - Faults/Mistakes - Where the result satisfies the operators intention but the intention itself was wrong
Linked to the SRK model
Violation
Violations are deliberate illegal actions that ignore or violate procedures
There are 2 types; Routine violations which can be done on a daily basis or Exception Violations which is when you have gone out of your way to deviate from the plan
Omission
Simply missing out a procedural step
Can be caused by distractions or interruptions
Latent errors
Hidden errors that lie dormant and will lull the pilot into a false sense of security
Incorrectly inputting a way point on a navigation system
Active Errors
Errors that have rapid/immediate consequences
Murphey’s Law
If anything can go wrong, it will do
If a system can be operated incorrectly, it will be at some point
The Error Chain - ‘Swiss Cheese Model’
Errors are cumulative and you can easily go from 1 to another to another
James Reason’s Concept
Each slice represents a system or process designed to prevent errors
Each hole represents an error or mistake
Can be fatal if all the holes align
Internal Error Generation
Caused by;
Action slips
Sensing errors
Perception/Representation errors - perceptual tricks
Decision making
False hypothesis - lack of situational awareness
Motivation and Arousal - Lower levels lead to errors
Distraction - Channelised attention or Dispersed Attention
Hungry
Fatigued
Lack of practice - deterioration effect - loss of skills
SHELL Model
S - Software
H - Hardware
E - Environment
L - Liveware
L - Liveware
Software
Checklists
Manuals
Hardware
Flight Deck design
Instruments
Man- Machine Interface (L-H)
3 Point altimeter increased error rates by 20%
Environment
WX - External
Environmental and ergonomics:
Temp
Humidity
Vibration
Noise
Liveware
Human
Reducing Errors
Reversible Errors - can delete or start again
Error Prevention - systems that prevent you doing things
Cross Monitoring - two of you plus automation cross cxing
Machine Monitoring Systems - alert to hazardous situations (GPWS and TCAS etc)
