If two safety managers independently of each other conducted a root cause
analysis of the same occurrence, there would most likely be two different root
cause statements.
One method used to arrive
at a coherent root cause
statement is to assign the
root cause to the pilot in
command. When multiple
root cause analyses are
conducted by different
persons or organizations of
identical hazards, or
incidents, a root cause that is
allocated, or assigned, to a
person is a predetermined
root cause. Justification for
assigning a root cause to a vehicle operator, a pilot, or maintenance person is often that they failed to follow standard operating procedures (SOP). Standard
operating procedures are tasks required to be completed by a person, and when items on the SOP are missed by a person, the root cause is assigned to that single missed item. When a root cause analysis leads to a reference document, other factors are excluded with no other options available. A reliable root cause analysis leads to one of four factors, which are human factors, organizational factors,
supervision factors or environmental factors, and is within the scope and
responsibility of the root cause analysis person, department, or organization.
The 5-Why analysis is a frequently used as a root cause analysis tool. A flaw with
the simple version of the analysis, is that after the first Why-question is asked, the
path is laid out for what direction the root cause with take. A more reliable root
cause analysis is to use a 5x5 matrix and ask the Why-question 25 times before
.conclude with a root cause statement. When the root cause has been established,
assign one of the one of the four factors as the primary root cause factors.
A root cause analysis is to
track the process backwards
to the fork-in-the-road where
a different action most likely
would have changed the
outcome. A root cause
analysis must be based on
the fact that the future was
unknown at the time of the
occurrence. When
conducting an analysis of an
incident, the outcome is
already known, which add an
additional challenge to define
an unbiased root cause
statement. Other challenges
are to overcome pressure from within the organization and public opinion to
immediately deliver a root cause statement, and to deliver a root cause of what is
beyond operational control, or scope of data collection sources. A user or client
may also demand that an airport or airline publish a root cause statement of a third-party contractor incident.
After an aircraft incident, the first Why-question is: Why did the aircraft crash? The
answer could be several, but the least challenging answer is that the pilot failed to
remain on the runway. This answer already points the finger at the pilot as being
the root cause. Since the analysis is named the 5-Why, let’s keep asking more
questions. The answer to the first question becomes the question for the second
answer. Why did the pilot fail to remain on the runway? Because the pilot failed to
apply proper control inputs. Next Why-question is: Why did the pilot fail to apply
proper control inputs? Answer number 3 is because the pilot did not recognize the
T.crosswind when landing. Why did the pilot not recognize the crosswind? Because
the pilot did not calculate the crosswind component prior to landing. The last
question, and question number five which is the root cause is: Why did the pilot
not calculate the crosswind component? Answer to number five and the root
cause is that the pilot failed to use the approach and landing checklist requirement
to check the crosswind component when with wind velocity is greater than 20 KTS.
This root cause analysis identifies many things that the pilot did not do. What is
lacking in the analysis is what the pilot did. During the times when a pilot failed to
process a specific task, the pilot did something else. Time does not evaporate, and
when a required task failed, that time period was filled with something else that
the pilot did. When assigning blame or a root cause to pilot failure, valuable
information of what actually happened are missed. What did not happen is
irrelevant to the root cause analysis. There are many things the pilot failed to do or
did not do. Some of these could be that the pilot failed acknowledge landing
clearance, the pilot failed to set bug-speed, the pilot filed to put on shoulder
harness, the pilot failed to touchdown in the landing area, or the pilot failed to
check that the parking brakes were off prior to touchdown and more. That a pilot
failed to complete a required task does not necessarily cause an accident. On the
other hand, that a pilot does something may cause an accident. A contributing
cause to the Everglades crash in 1972 was that the crew did their best to fix a
failed light. They filled their time with other tasks than aircraft control tasks, which
is an important fact to determine the root cause. The factor causing the airplane to
crash outside of runway pavement was that the cross wind within seconds
increased from 21KTS to 48KTS during the landing and the pilot encountered an
extreme downdraft in the overshoot.
Human factors and human errors are in the aviation industry accepted as being the
same thing. However, human error is a symptom of trouble deeper inside a system
or an organization. On the other hand, human error is also a symptom of a
successful organization. There are organizations where human errors are
integrated with the system and need to be there for the organization to exist and
prosper. It is the system itself that is set up for human errors.Conventional wisdom is that human error is a ”bad” thing when using emotions to
describe an event. Human error is a sub-category of human factors. Simplified,
human factors are how a person react when one or more of the five senses, vision,
hearing, smell, taste, and touch are triggered. Human factors are also how external
forces, or events, e.g., fatigue, weather, illumination and more, affect
performance.
In an organization where
there are overwhelming
events of human errors, the
organization operates within
a system that is prone to
these errors. Tow examples
are car races or air races,
where the systems (race to
win) are setting each driver
and pilot up for human error,
or a crash. Both a car race and
an air race organizers have
requirements and systems in
place to reduce harm to drivers, pilots, or spectators These systems are designed for human errors. Imagine how successful a car race
would be if the speed was limited to 50MPH, or if an air race required airplanes to fly between gates separated a mile apart.
For a corrective action to be applied to a root cause, an operator must understand the finding, and the associated hazard. System level findings identify the system and regulatory requirement that failed, and a process level findings identify the process that did not function as expected. To develop an effective corrective action plan (CAP), an SMS enterprise must comprehend the nature of the system
or process deficiency which led up to the error.
Errors are symptoms or displays.System level findings group non-compliances that show a system-wide deficiency of an SMS enterprise system. Examples of systems are the safety management system, a quality assurance system, operational control system, maintenance
control system, training system, or airport preventive maintenance system.
Process level findings identify processes that did not function and resulted in an
incident or regulatory non-compliance. Examples of processes are documentation
control process, safety risk management process, system analysis process, audit
process, or an airport emergency response plan exercise process. It is vital for the
success of a corrective action plan that it is applied to the correct system or
process, and that it is applied to a system or process as applicable to the finding.
The purpose of a factual review of a finding is to define the scope of the problem
in the system. An SMS enterprise must clearly Identify policies, processes,
procedures, and acceptable work practices involved that allowed the non-
compliance to happen. Processes and procedures are usually established through
documentation, but also consider undocumented work practices, attitudes and
tolerances that may have developed and drifted over time. An SMS enterprise
attacks the finding by defining the problem and make a clear statement of how
widespread the non-compliance is in the system. A finding could be isolated to one
area of the organization or spread into other departments and functional areas of
an SMS enterprise. When explaining how widespread the problem is, write it in
clear text with clarification and directions. Problems are addressed in 3D measured
in time (speed), space (location), and compass (direction). After the hazard, or
problem has been assigned a corrective action plan, the plan is put into action
immediately.
A system failure could be that the electrical grid to an airport failed. It is beyond
the scope and responsibility of an airport to conduct a root cause analysis of the
grid system, since airport operators does not control, maintain, or monitor the
power grid. The root cause analysis is the responsibility of the power grid operator.
An airport operator would conduct a root cause analysis to establish why theirbackup generator also failed when the power grid failed. Both root causes are
allocated to either human factors, organizational factors, supervision factors or
environmental factors. Root cause allocation becomes opinions of what system the
corrective action plan should be applied to.
All systems include multiple
sub-systems. A vehicle system
is to move persons, goods, or
services from one point to
another. Sub-systems of a
vehicle are the transmission
system, tire system, control
system and more. Should a
transmission system fail, is not
a failure of the entire vehicle
system, but is simply a
transmission system failure.
When the transmission fails, the task becomes to assign a root cause opinion why it failed, implement a CAP, test, and monitor if the repair was successful. It is vital for a successful safety management system that accountable executives accept the fact that root cause statements are opinions only.
OffRoadPilots
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