The document discusses common root causes of data center outages according to a survey, which found that the most frequent causes were UPS battery failure, UPS capacity being exceeded, accidental EPO/human error, and UPS equipment failure. The majority of respondents believed the outages could have been prevented by measures like improving equipment, increasing budgets and staffing, and performing preventative maintenance. Over half of organizations responded to outages by repairing, replacing, or purchasing additional IT or infrastructure equipment.
4. marine accident
year project to Common patterns that were found included:
marine accidents, • Human error continues to be the dominant factor in
yze the contents. maritime accidents, contributing toABS to 85 percentPAPERS 2006
80 TECHNICAL
er understand the of accidents.
• Based on USCG data, for all accidents over the efficient approach for in
reporting period of 1999 to 2001, approximately 80 documenting marine inciden
to 85% of the accidents analyzed involved human 1developed the MaRCAT m
error. Of these, about 50% of maritime accidents and combining the best te
were initiated by human error, and another 30% of proving and improving the
were associated with human error. MaRCAT’s application duri
• In MARS reports (voluntary mariner self reporting The ABS MaRCAT approa
of accident and near misses), mariners note human caters to the unique need
error in the majority of reports, and chiefly attribute including human element;
accidents and near misses to: lack of competence, structural and security conc
knowledge and ability; human fatigue; workload; ABS MaRCAT approach are
manning; complacency, and; risk tolerance.
• Assist clients with inve
• USCG data on offshore pollution events in (e.g., groundings, coll
California suggests that 46% are caused or incidents (minor to maj
associated with human error. to their vessels and facil
• For accidents associated with pollution events in the
• Allow analysis of losses
State of California, accident causes are chiefly
the environment, human
attributed to failures of situation awareness (94%).
reliability, quality or bus
• Among all human error types classified in numerous
ABS TECHNICAL PAPERS 2006
databases and libraries of accident reports, failures • Provide ABS clients wit
TRENDING THE CAUSES OF MARINE INCIDENTS
of situation awareness and situation assessment incident investigators in
overwhelmingly predominate, being a causal factor
D.B. McCafferty, American Bureau of Shipping, USA analyses and in provid
C.C. Baker, American Bureau of Shipping, USA
in about 45% (offshore) to about 70% (ships) of the identifying, documentin
recorded accidentsFrom Marine Incidents 3 Conference held in London,(see
Presented at the Learning
associated with human error
January 25-26, 2006, and reprinted with the kind permission of the Royal Institution of Naval Architects
accidents and near misse
SUMMARY
Figure 1, below). • Assist and facilitate
10. • Procedures & checklists
• Verification & redundancy
• Eliminating human factor where it’s
unnecessary
• Focusing human effort where it’s actually
needed
11. Procedures & checklists
• A lot of what we do is following known
procedures
• If we write it down & follow the
instructions, we can focus on what is
special, not on doing the usual steps
• Also, we won’t forget any of the usual steps
when situation goes sideways
17. ctors 35(2), pp. 28-43.
COCKPIT CHECKLISTS:
CONCEPTS, DESIGN, AND USE
Asaf Degani
San Jose State University Foundation
San Jose, CA
Earl L. Wiener
University of Mami
Coral Gables, FL
18. task-checklists for almost all segment of the flight, i.e., PREFLIGHT, TAXI, BEFORE
LANDING, etc.; and in particular before the critical segments: TAKEOFF, APPROACH,
and LANDING. Two other checklists are also used on the flight-deck: the abnormal and
emergency checklist. This paper will address only the normal checklist.
We believe that normal checklists are intended to achieve the following objectives:
1. Provide a standard foundation for verifying aircraft configuration that will attempt
to defeat any reduction in the flight crew's psychological and physical condition.
2. Provide a sequential framework to meet internal and external cockpit operational
requirements.
3. Allow mutual supervision (cross checking) among crew members.
4. Dictate the duties of each crew member in order to facilitate optimum crew
coordination as well as logical distribution of cockpit workload.
5. Enhance a team concept for configuring the plane by keeping all crew members
“in the loop.”
6. Serve as a quality control tool by flight management and government regulators
over the flight crews.
Another objective of an effective checklist, often overlooked, is the promotion of a
positive “attitude” toward the use of this procedure. For this to occur, the checklist must
be well grounded within the “present day” operational environment, so that the flight
crews will have a sound realization of its importance, and not regard it as a nuisance task
19. Various types of checklist devices have evolved over the years. Among them are the
scroll, mechanical, and vocal checklist (Degani and Wiener, 1990; Turner and Huntley,
1991). More modern ones involve computer-based text displayed on a CRT and
electronic checklist devices that sense sub-system’s state (Rouse, Rouse, and Hammer,
1982; Palmer and Degani, 1991).
The paper checklist is the most common checklist device used today in commercial
operation. It has a list of items written on a paper card (see Figure 1). Usually, the card is
held in the pilot’s hand. Because of the wide prevalence of this device, it will be the focus
of this paper.
Sanders and McCormick (1987) state that “because humans are often the weak link in the
system, it is common to see human-machine systems designed to provide parallel
redundancy” (p. 18). A similar principle of backup and redundancy is applied in the
checklist procedure. There are two types of redundancies embedded in this procedure.
The first is the redundancy between configuring the aircraft from memory and only then
using the checklist procedure to verify that all items have been accomplished properly
(set-up redundancy). The second is the redundancy between the two or three pilots
monitoring each another while conducting the checklist procedure (mutual redundancy).
The Method
There are two dominant methods of conducting (“running”) a checklist—the do-list and
the challenge-response. Each is the product of a different operational philosophy.
Do-list. This method can be better termed “call-do-response.” The checklist itself is used
to lead and direct the pilot in configuring the aircraft, using a step-by-step “cookbook”
approach. The setup redundancy is eliminated here, and therefore, a skipped item can
easily pass unnoticed once the sequence is interrupted.
Challenge-response. In this method, which can be more accurately termed “challenge-
20. The first is the redundancy between configuring the aircraft from memory and only then
using the checklist procedure to verify that all items have been accomplished properly
(set-up redundancy). The second is the redundancy between the two or three pilots
monitoring each another while conducting the checklist procedure (mutual redundancy).
The Method
There are two dominant methods of conducting (“running”) a checklist—the do-list and
the challenge-response. Each is the product of a different operational philosophy.
Do-list. This method can be better termed “call-do-response.” The checklist itself is used
to lead and direct the pilot in configuring the aircraft, using a step-by-step “cookbook”
approach. The setup redundancy is eliminated here, and therefore, a skipped item can
easily pass unnoticed once the sequence is interrupted.
Challenge-response. In this method, which can be more accurately termed “challenge-
verification-response,” the checklist is a backup procedure. First, the pilots configure the
plane according to memory. Only then, the pilots use the checklist to verify that all the
items listed on the checklist have been correctly accomplished. This is the most common
checklist method used today by commercial operators.
-5-
21.
22.
23. been created by people and can be documented and understood. But when it comes
to people, we are faced with a system element that comes with no operating manual
and no performance specifications, and that occasionally performs in ways not
anticipated by the system designers. Some of these failures can be easily explained,
an arithmetic error for example, while others are harder to predict. Although
individuals differ, researchers have discovered general principles of human
performance that can help us to create safer and more efficient systems. The focus
of this paper is on the functioning of people as elements of maintenance systems in
aviation.
The cost of maintenance error
Since the end of World War II, human factors researchers have studied pilots and
the tasks they perform, as well as air traffic control and cabin safety issues. Yet
until recently, maintenance personnel were overlooked by the human factors
profession. Whatever the reason for this, it is not because maintenance is
insignificant. Maintenance is one of the largest costs facing airlines. It has been
estimated that for every hour of flight, 12 man-hours of maintenance occur. Most
significantly, maintenance errors can have grave implications for flight safety.
Accident statistics for the worldwide commercial jet transport industry show
maintenance as the ‘primary cause factor’ in a relatively low four per cent of hull
loss accidents, compared with flight crew actions that are implicated as a primary
2
cause factor in more than 60 per cent of accidents. Yet primary cause statistics
may tend to understate the significance of maintenance as a contributing factor in
accidents. In 2003, Flight International reported that ‘technical/maintenance
failure’ emerged as the leading cause of airline accidents and fatalities, surpassing
controlled flight into terrain, which had previously been the predominant cause of
26. • Use procedures where it makes sense
• at least, write stuff down
• Automation, verification, redundancy
• scripting not only for doing stuff, also for
making sure it worked
• Usability of our panels & dashboards