• Current MCAS Results. This describes the results o f responses from the most recent iteration o f MCAS that had been conducted within the organization, o Likert scale value responses for each o f the 43 close-ended questions were
averaged across all participant responses,
o Where appropriate, all 43 MCAS responses were aggregated by equal weighted averaging to provide a single Likert scale value,
o Additionally, questions which composed specific MOSE areas (i.e., Process Auditing, Reward System, Quality Control, Risk Management, Command and Control, and Communications / Functional Relationships) were aggregated by equal weight averaging to provide single Likert scale values,
o Since Question #21 was written with negative connotation (i.e., evaluation o f a condition that adversely affected safety), in order for all responses to be
aligned, the inverse o f the value was obtained by subtracting the response value from 6 (e.g., response o f strongly disagree = 1; 6 - response value; 6 -
1=5; becomes strongly agree),
o When results o f multiple units were obtained, quartiles for the distribution were defined. An organization's aggregated and averaged Likert scale value were assigned a quartile ranking as depicted below in Table 13.
Table 13. MCAS Result Quartile Distribution Quartile Description
Q i Lowest Likert scale values, 0 < x < 25%
q 2 25% < x < 50%
Q3 50% < x < 75%
q 4 Highest Likert scale values, 75% < x < 100%
administered immediately prior to the Current MCAS Results. Its numerical value was derived similarly to the means used for Current MCAS Results using
corresponding Likert Scale values and quartiles as defined in Table 13, above.
The time increment between Previous and Current MCAS Results was not constant and varied considerably among the organizations.
Future MCAS Results. This describes the results o f responses from the MCAS administered immediately subsequent to the Current MCAS Results. Its numerical value was derived similarly to the means used for Current MCAS Results using corresponding Likert Scale values and quartiles as defined in Table 13, above.
The time increment between Previous and Current MCAS Results was not constant and varied considerably among the organizations.
Inter-Period MCAS Transition. This component represents the change in corresponding quartile assignment based upon aggregated and averaged Likert scale values derived from two immediate iterations for administering the MCAS (i.e., the delta in quartile obtained between Previous and Current MCAS Results).
This was calculated by:
o Inter-Period MCAS Transition =
Current MCAS Results - Previous MCAS Results (EQ 16) o The value o f the transition could be calculated by the numerical difference
in the whole number change in quartiles (i.e., range o f -3, -2, -1, 0, 1,2, 3) Inter-Period Mishap Occurrence This element is used to describe whether or not an Aviation Flight Mishap occurred during the time inter-period between
successive administrations o f the Past and Current MCAS and associated responses. The range o f responses was binary, either YES or NO.
• Future Mishap Occurrence. This factor describes whether or not an Aviation Flight Mishap occurs during the time inter-period between success delivery o f the Current and Future MCAS and respective responses. The range o f responses was binary, either YES or NO.
3.5.3. E X O G EN O U S CO M PO N EN TS
• Current Organizational Climate. Although not directly observable or measurable, this element was defined to represent the capability o f the Current MCAS Results to accurately represent an organization's existing climate with respect to
operational safety within the context o f the MOSE foundation. This definition enabled application o f HMMs which contained hidden states (safety climate), observations (MCAS) results, and probabilities o f observation and transition occurrences.
• Previous Organizational Climate. Similar to Current Organizational Climate, this component described the adequacy o f the Past MCAS Results to accurately represent the organization’s operational safety climate during the time period between administration o f the Past and Current MCASs.
3.5.4. EX C L U D E D C O M PO N EN TS
Endogenous and exogenous components listed above were supportable by the sufficiency and scope o f the data provided by the U.S. Naval Safety Center for this
research effort. Within this section, excluded components are listed which are within a sphere o f influence that could impact MCAS Results and Mishap occurrence;
however, insufficient data were provided to enable their definition or development.
• Maintenance Required. A measure o f the work effort necessary to facilitate attainment o f operational aircraft. This includes required pre- and post-flight servicing and inspections, preventative maintenance, and the correction o f known discrepancies that are sufficiently severe as to prevent aircraft from being
characterized as safe for flight.
• Maintenance Performed. This is an overarching classification o f the types o f maintenance performed by the squadron comprised o f inspections, servicing, handling, on-equipment corrective and preventive maintenance, incorporation o f technical directives, and record keeping and reports preparation.
• Aircraft Flight Operations. Actual flights in which the aircraft are launched and the assigned mission is successfully completed.
• Collateral Damage. Impairment to linked system elements which are caused by component breakdown, incorrect operation, or failure and result in creation o f new Aircraft Discrepancies. Collateral damage may also be caused from incorrectly performed maintenance.
• Preventative Maintenance is a subset o f maintenance performed, and it describes the effort which is conducted to maintain the aircraft in adequate material condition to accomplish assigned missions. Preventative maintenance is a proactive effort undertaken to mitigate creation o f Aircraft Discrepancies and related component failures.
• Operational Demand. Operational demand. A measure o f the demand placed upon the squadron thorough assignment o f respective missions. Operational demand is composed of two inputs: tasking and employment scheduling, o Tasking. The number o f flight sorties required to be flown in order to fulfill
training or currency requirements from the squadron's operations department or those missions assigned from superior commands,
o Employment scheduling. For operational squadrons that deploy, Naval aviation has adopted the Fleet Response Plan based on a notional 27-month Inter-Deployment Readiness Cycle (IDRC) which includes 6 months for aircraft maintenance, followed by 6 months for training, and a 15 month employment window. During the employment window the squadron is expected to sustain a high degree o f readiness which may include forward deployed operations. A depiction o f the IDRC is shown in Figure 14. The IDRC driven employment schedule is the critical driver for squadron receipt of operational funding, personnel, aircraft and associative weapons systems (e.g., laser designators, forward looking infra-red pods, etc.) inventory, required readiness levels, and operational demand.
M o n th 0 3 6 ■> 12 If* 18 21 24 2 /
Employability
Deployment
Maintenance Training
Funding
Figure 14. Inter-Deployment Readiness Cycle [CNAF Training and Readiness Review Conference, 2003]
• Assigned Personnel. Sufficient manpower is required to be assigned to the
squadron in order to accomplish assigned missions. Personnel are ordered into the squadron to fill billets listed in the authorized manpower documents, and they are rotated out when their tours o f duty are complete.
• Assigned Aircraft. Represents the number o f aircraft assigned to the organization that are maintained and tasked to meet Operational Demand.
• Available Parts Inventory. Very few replacement parts are assigned directly to the squadron inventory. These replacement spare items are normally limited to consumable components or bit / piece parts such as hardware (nuts, bolts, etc.) or other items that routinely require removal and replacement due to wear. Primarily specific replacement components are maintained in a ready-for-issue status by respective supply departments located at either naval air station or shipboard from which the squadron is operating. A lack o f parts availability may be mitigated through cannibalization o f parts from other aircraft. This results in additional maintenance performed to remove the needed component from one airframe and
the subsequent effort to replace it when the needed spare part becomes available through the supply system.
• Quality Assurance Inspections. Inspections o f conducted maintenance that ensures quality workmanship. Quality Assurance (QA) is fundamentally employed to prevent the occurrence o f defects. The concept embraces all events from the start o f the maintenance operation to its completion and is the responsibility o f all maintenance personnel. [CNAFINST 4790.2 Vol. 1, 2005, p. 14-2.] Highly skilled representatives are assigned to the QA division to inspect maintenance work for conformance to technical requirements and to audit work centers for evaluation o f plans, policies, procedures, products, directives, and records.
3.6. SE L E C T IO N OF BA YESIAN N E T W O R K M O D EL IN G A S TH E