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School of Engineering
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MANU2464 Integrated Logistics Support Management
Assessment 3
Assessment Type: Essay
Due date: Sunday of Week 6 (11:59pm)
Weighting: 50%
Overview
In this assessment, there are four main parts. To begin you'll need to choose a situation or system you would like to
understand better. You'll use this system for each of the four parts of this assessment.
Learning Outcomes
This assessment is relevant to the following outcomes:
3. Analyse and quantify risks in logistics support using mathematical techniques and develop approaches to
mitigation of the analysis outcomes.
4. Identify and analyse, within the content of the logistics support system, all functions such as material flows,
distribution, manpower and personnel, training and training devices, and the sustaining of life cycle
maintenance, operation and support, for the development of improvement plan.
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Assessment details
Answer the following questions:
Part 1 (20 Points)
Problem 1:
The cu
ent reliability of Complex GA Aircraft Systems is unknown. The ability to gain insight into this unknown will
provide the aviation community with a valuable benchmark that will assist in the development of reliability and safety
equirements for future aircraft. This benchmark must be established in order to ensure that technology
development, design guidelines, and work on certification standards progresses towards the effective goal of
affordable technologies for small engine airplanes.
In order to provide relevant information regarding GA aircraft reliability that is conducive to the engineering goal of
ensuring development of an affordable, advanced single pilot transportation aircraft, it is necessary to include
airplanes that share many of the characteristics of future aircraft design. The proposed future aircraft design will
consist of an aircraft with a cruise speed of 160 knots and a range of 700 nm. This aircraft is considered to be a
single pilot, four-place, light-single engine piston aircraft with near all-weather capability.
Complex GA Aircraft have retractable landing gear, flaps, and a constant-speed propeller. The systems of the future
aircraft will be very similar to cu
ent Complex GA Aircraft Systems and therefore, represent the population of GA
aircraft used in this study. Where the futuristic airplane model did not provide guidance into design complexity or
definition, typical Complex GA Aircraft architecture was assumed.
The approach used in performing the reliability study is to define the Complex GA Aircraft Systems and Subsystems
for complex aircraft, collect failure data from a random sample of complex aircraft, and then analyze the data in order
to determine reliability estimates. To accomplish this, Complex GA Aircraft were divided into the following four
systems indicating primary function:
Airframe - any component or structure that is essential to the structural integrity of the aircraft.
Control - any component that controls the aircraft’s attitude, heading, and altitude or changes the aerodynamic
characteristics of the aircraft in the air or on the ground (excluding powerplant).
Electrical - the lighting system and any components involved in the source and distribution of electrical power.
Powerplant - any component or system that is essential to developing thrust for the aircraft.
After researching many data sources and collection methods, it is determined that failure data obtained from
operational aircraft would provide a good benchmark of cu
ent system reliability and that logbooks of complex
aircraft could provide the source of this failure data. The logbooks, required by law to be kept by aircraft owners, are
eviewed by the Federal Aviation Administration (FAA) and cover the history of maintenance performed on the
aircraft. Work performed on the aircraft is logged in these books and is signed by the mechanic who performs the
work. This provides a good source of historical data regarding airplane component failures and replacements.
The method selected for estimating the reliability of the GA Aircraft Systems is to first determine the proper
distribution that models the collected failure data for each sub-system. This is accomplished by placing the failure
data collected from the total number of aircraft sampled into a database and separating them according to the
defined subsystems. By constructing probability plots for each subsystem, distributions that describe the failure
process can then be obtained. This information can then be used to determine the probability distribution
parameters.
Airframe has many components connected in series and if any of the components fails, airframe system fails. Here is
the data for airframe failure times.
Given the following 20 failure times (hours):
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
Assume failure times are distributed according to the two-parameter Weibull distribution.
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a). By the graphic method or the method of least squares, find the Weibull parameters. The Weibull shape
and scale parameters must be estimated using the Weibull probability plot paper. (2 points)
). Determine the reliability of the Airframe at 300 hours. (2 points)
Aircraft Control system (ACS) also has numerous parts connected in series and if any of the parts fails the aircraft
control system fails. Assuming Weibull distribution, the failure times in hours data are given:
XXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX
c). Find the Weibull parameters using the Weibull probability paper. (2 points)
d). Determine the reliability of Aircraft Control system at 300 hours. (2 points)
Powerplant system also has many components which are used to develop thrust for the aircraft. The
failure times for the Powerplant system are in hours:
270
380
1220
1750
2620
3320
4060
5200
6450
e). Estimate the Weibull parameters using Weibull probability paper. (2 points)
f). Determine the reliability of the Powerplant system at 300 hours. (2 points)
Electrical system has five components involved in the source and distribution of electrical power. They are
connected in mixed order (series and parallel mixed, as shown in the diagram below) and the failure times
in hours are distributed as following:
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Electrical System Diagram
• Component 1 has been observed to follow a Normal distribution with a mean lifetime (μ) of
400 hours and standard deviation (σ) of 120 hours.
• Component 2 has been observed to follow an Exponential distribution and the mean time to
failure (MTTF) is 450 hours.
• Component 3 has been observed to follow a Log-Normal distribution, and the mean value
(μ) of the natural logarithm of the life time of component is 6 and the standard deviation (σ) is
1.5.
• Component 4 has demonstrated a Gamma failure distribution with α = 4 and λ = 0.003
(failures per hour).
• Component 5 has Normal failure distribution with a mean lifetime (μ) of 330 hours and
standard deviation (σ) of 100 hours.
g. Determine the reliability of electrical system at 300 hours. (4 points)
h. Suppose the desired electrical system reliability is 99%. What improvements are needed in the electrical
system design to increase the reliability to 99%? (2 points)
Further, Complex GA Aircraft’s four systems indicating primary function are connected in series:
Systems Diagram
1. Determine the Reliability of Complex GA Aircraft system at 300 hours. (2 points)
Part 2 (13 points)
Problem 2:
A recent study conducted in the United States by McKinsey Consultants has found that Australia pays
more than other nations for its equipment to maintain a strong defense industry. The findings indicated that
Australia ranked last out of 33 countries on a measure of defense equipment output versus expenditure. “In
general, countries that make it a point to support their domestic defense industries have higher
procurement costs than those that rely on imports”, the report says.
The Australian government is very supportive of acquiring a new fleet of 12 submarines to replace the
trouble-plagued Collins class vessels. ASPI put a price tag of $9 billion on buying off-the-shelf European
submarines, and $36 billion on an Australian design and build. The choices are between an off-the-shelf
submarine, a reworked Collins or one designed from the ground up. But an Australian design-and-build
could provide significant potential industrial and military capability opportunities because of its size and
duration, among other things. The government is also committed to ensuring that certain strategic industry
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capabilities remain resident in Australia. (0.8 points for each part below)
Based on the concept and knowledge you gained from this course:
1. Define the mission of government’s plan of acquiring the fleet of submarines.
2. Define all basic system performance parameters and the planned operational deployment.
3. Define the system life cycle and utilization requirements, and operational environment.
4. Identify system availability, dependability, readiness or equivalent operational effectiveness
factors.
5. Define the effectiveness factors for the system support capability.
6. Specify the levels of maintenance and identify the basic maintenance functions for each level.
7. Establish the level-of-repair policies including level-of-repair decisions, criteria for test and support
equipment at each level of maintenance, personnel quantities and/or skills at each level of
maintenance, and responsibilities for maintenance.
8. Define and establish the system operational and maintenance functions and appropriate
functional relationships and interfaces.
9. Allocate the maintainability, supportability and cost factors to the logistic support infrastructure
where applicable.
10. Perform and adequately document the trade-off evaluations and analyses to support all logistic
support requirements.
11. Are the selected test and support equipment items compatible with the prime equipment to do the
job? Have logistic support requirements for the selected test and support equipment been defined?
12. Are the types and quantity of spare
epair parts compatible with the level-of-repair analysis? Are
they designated for a given location appropriate for the estimated demand at that location? Explain
in detail.
13. Identify spare
epair part requirements and minimize to the maximum extent possible. Also, define
an inventory safety stock level.
14. Establish a supply availability requirement (the probability of having a spare available when
equired).
15. Specify the maintenance personnel and their training requirements. Have specific training
programs been planned? Are the planned training programs compatible with the personnel skill
level requirements specified for the performance of maintenance tasks?
16. Are the maintenance procedures compatible with the supportability analysis data, and the level of
activity performed at the location where the procedures are used?
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Part 3 (17 points)
Problem 3:
Suppose we would like to own and operate a Motor Boat dealership in the coastal region of Melbourne city. We would
sell a range of new motor boats and repair existing boats