8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 1/34
AIRLINE SAFETY AND THE
EFFECTS OF MAINTENANCE
3rd Annual European Airline Engineering & Maintenance Conference
Zurich, 21-22 February 2007
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 2/34
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 3/34
Review of Maintenance Error Events
The Contribution of Maintenance Error to Accident
Statistics
Safety Systems and Human Performance in
Maintenance
Maintenance Error and Business Risk
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
PRESENTATION OVERVIEW
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 4/34
…
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
ALOHA BOEING 737
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 5/34
…
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 6/34
…
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
AIRBUS A320 SPOILER INCIDENT
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 7/34
…
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
BOEING 737 DOUBLE ENGINE OIL LOSS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 8/34
G-CEPR
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 9/34
777 fuel panel
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 10/34
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
Procedural deviations
Inadequate regulatory oversight
Inadequate maintenance programme
Failure to respond to cues and warnings
Inadequate promulgated information
COMMON FACTORS IN THESE INVESTIGATIONS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 11/34
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
REVIEW OF MAINTENANCE ERROR EVENTS
Non-use of available resources
Failure to communicate
Design deficiency
Failure to anticipate effects on the operation of
the aircraft
Inadequate maintenance environment
Human performance limitation
Inadequate management oversight
Incorrect parts or tools
Inadequate knowledge or training
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 12/34
Accident rate plots
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
THE CONTRIBUTION OF MAINTENANCE ERROR
TO ACCIDENT STATISTICS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 13/34
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
THE CONTRIBUTION OF MAINTENANCE ERROR
TO ACCIDENT STATISTICS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 14/34
Most maintenance error events investigated were
INCIDENTS not ACCIDENTS
Maintenance related occurrences form a larger
proportion of total incidents investigated by AAIB
than accidents.
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
THE CONTRIBUTION OF MAINTENANCE ERROR
TO ACCIDENT STATISTICS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 15/34
THE COSTS OF A MAINTENANCE EVENT
Rework/re-instatement costs
Additional hangar time costs
Repair costs for consequential damage
Maintenance re-scheduling and knock-on delays
Operational schedule related costs
Compensation costsCost of hiring a replacement aircraft
Business costs –
obtaining and retaining market share
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
THE CONTRIBUTION OF MAINTENANCE ERROR
TO ACCIDENT STATISTICS
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 16/34
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
SAFETY SYSTEMS AND HUMAN PERFORMANCE
IN MAINTENANCE
Maintenance Error Management Systems
Safety Management SystemsUK CAA CAP 716
Transport Canada has SMS requirement
US FAA - intent for the future?
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 17/34
SAFETY
MANAGEMENTSYSTEMS
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
SAFETY SYSTEMS AND HUMAN PERFORMANCE
IN MAINTENANCE
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 18/34
LIMITATIONS OF HUMAN PERFORMANCE
Perception and Cognitive limitations
Physical limitations
PERFORMANCE LEVEL ERROR TYPE
Skill-based level Slips and lapsesRule-based level RB mistakes
Knowledge-based level KB errors
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
SAFETY SYSTEMS AND HUMAN PERFORMANCE
IN MAINTENANCE
Man errs as long as he strives.
Goethe
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 19/34
ERROR TYPE MAINTENANCE EXPERT
DATA ASSESSMENT
Skip a step 0.15 0.001
Skip a task 0.026 0.001Ignore a warning/caution 0.042 0.013
Intentionally deviate 0.042 0.32
Improperly remove/replace 0.033 0.02
Improperly repair 0.089 0.0023
Incomplete installation 0.089 0.01
Improperly adjust 0.09 0.1 Allow/cause debris to enter 0.17 0.01
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
SAFETY SYSTEMS AND HUMAN PERFORMANCE
IN MAINTENANCE
Source Ostrom et al, INEEL
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 20/34
PROCEDURES MITIGATE RISK OF HUMAN ERROR
Clear documentation
Parts kitsChecklists
Inspections
Function checks
Even pre-flight checks
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
SAFETY SYSTEMS AND HUMAN PERFORMANCE
IN MAINTENANCE
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 21/34
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 22/34
EXAMINING THE RELATIONSHIP BETWEENBUSINESS RISK AND MAINTENANCE ERROR
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
MAINTENANCE ERROR AND BUSINESS RISK
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 23/34
…
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
MAINTENANCE ERROR AND BUSINESS RISK
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 24/34
…
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
MAINTENANCE ERROR AND BUSINESS RISK
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 25/34
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 26/34
…
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
MAINTENANCE ERROR AND BUSINESS RISK
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 27/34
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
MAINTENANCE ERROR AND BUSINESS RISK
Non- compliance is the norm in
many situations in daily life.
It is human nature to resolve
conflicts pragmatically.
Pragmatic solutions become‘Norms’.
Norms become ‘the way we do
things around here’.
Non - compliance becomes part
of the culture.
The non- compliance may
continue for years before the risk
emerges.
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 28/34
3rd Annual European Airline Engineering & Maintenance Conference
Airline Safety and the Effects of Maintenance
MAINTENANCE ERROR AND BUSINESS RISK
JUST CULTURE
Validity of the ‘Just’ culture rather than ‘blame’ or ‘no-
blame’.
SUBSTITUTION TEST
The substitution test – if another mechanic would have
done the same thing, then the issue is an… organisational problem.
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 29/34
MAINTENANCE ERROR AND BUSINESS RISK
BUT – there are hidden risks of rule-breaking…
If your organisation experiences rule-breaking, then it is
exposed to an unknown level of risk.
Dual risk –
1 the risk that the rule was intended to prevent:
(when we break the rule, we do not know the extent
of our exposure)
2 The risk of being caught out.
(Fines, litigation, Insurers deny claims)
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 30/34
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 31/34
Unexpected consequences!
‘XXX’ was the mechanic who fitted a non-standard
titanium strip to a DC-10...
‘He allegedly fixed the titanium alloy part instead of a
softer metal strip in the maintenance unit in Houston,
Texas, even though its use was not sanctioned by UScivil aviation authorities.
‘His supervisor was questioned in June by the judge but
has thus far not been put under criminal investigation.
‘The airline itself was placed under investigation formanslaughter and injuries in March, but has vowed to
fight any charges that may ensue’.
MAINTENANCE ERROR AND BUSINESS RISK
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 32/34
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 33/34
In 1994 AAIB stated: ‘The Civil Aviation Authority shouldformally remind engineers of their responsibility to ensure
that all work is carried out using the correct tooling and
procedures, and that they are not at liberty to deviate
from the Maintenance Manual but must use all availablechannels to consult with a design authority where
problems arise; if full compliance cannot be achieved the
engineer is not empowered to certify the work’.
[Airbus A320, G-KMAM AAIB Report 2/95, Safety
Recommendation 94-41]
This is still the only way forward.
MAINTENANCE ERROR AND BUSINESS RISK
8/12/2019 Airline Safety and Effects of Maintainence Alan Simmons
http://slidepdf.com/reader/full/airline-safety-and-effects-of-maintainence-alan-simmons 34/34
THANK YOU FOR YOUR ATTENTION
3rd Annual European Airline Engineering & Maintenance Conference