Lean Aerospace Initiative
Lean Aerospace Initiative
Plenary Workshop
Plenary Workshop
Cycle Time Reduction with Part
Cycle Time Reduction with Part
Synchronization
Synchronization
March 31- April 1, 1998 March 31- April 1, 1998 Presented By: Presented By: Tom Shields Tom Shields MIT MITInitiative
Outline
Outline
l lContext
Context
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Design and management of
Design and management of
complex manufacturing
complex manufacturing
systems
systems
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Engine sector research
Engine sector research
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Engine Study results
Engine Study results
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System characteristics
System characteristics
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Initiative
Achieving Lean:
Achieving Lean:
Some Accepted Wisdom
Some Accepted Wisdom
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Customer satisfaction
Customer satisfaction
– Produce to actual demand
– Provide predictable output & rapid response to undesired events
– Desired quality
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Continuous Improvement
Continuous Improvement
– Systemic
Initiative
Customer Satisfaction
Customer Satisfaction
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l Produce to actual demandProduce to actual demand – On time delivery
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l Provide predictable output & rapid Provide predictable output & rapid response to undesired events
response to undesired events – Low variability in throughput time
– Ability to recover schedule
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l Desired qualityDesired quality
– Fitness to standard
– Fitness to use
Initiative
Continuous Improvement
Continuous Improvement
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Aspects
Aspects
– Action based on facts/data
– Focus on the vital few Continuous Improvement = Systemic Improvement Iterative Improvement +
Initiative
Key Aspects of Continuous
Key Aspects of Continuous
Improvement
Improvement
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Action based on facts
Action based on facts
– Understanding of the process
– Example: Flow chart
– Use data as the basis for decision making
– Example: Check sheet (how often do certain events happen)
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Focus on the vital few
Focus on the vital few
– Identify causes
Initiative
Research Project: Design &
Research Project: Design &
Management of Complex Systems
Management of Complex Systems
ll Key QuestionsKey Questions
– What enables flow optimization to reduce cycle time?
– What are other manufacturing system elements that enable this reduced cycle time?
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l MethodMethod
– Investigate similar products in each sector
– Focus on assembly operations
– Measure key performance metrics
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l ProgressProgress
– Engine sector completed
Initiative
Engine Sector Research
Engine Sector Research
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Three sites
Three sites
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Studied final assembly of engines
Studied final assembly of engines
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Research focus
Research focus
– Build times
– Sources of delay
– Delivery history
– Manufacturing system performance
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Subsequent investigation of supplier
Subsequent investigation of supplier
network
Initiative
Engine Sector Study Results
Engine Sector Study Results
Customer Satisfaction = On Time Delivery
Customer Satisfaction = On Time Delivery
Delivery history
Delivery history
Site
Late
On Time
A
35%
65%
B
30%
70%
Initiative
Engine Sector Study Results
Engine Sector Study Results
(Con’t)
(Con’t)
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l Key attributes Key attributes of superior of superior performance: performance: – Build on time – Predictable build time 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 B1 B2 A1 A2 C2 C1
Site Engine Lines
Normalized Build Time
(actual/planned build time)
Average Build Time Shortest Build Time Longest Build Time Part Count
Initiative
Sources of Build Delay
Sources of Build Delay
A
A
11B
B
22C
C
Nonattributable
Nonattributable
47%
47%
-
-
-
-Parts shortage
Parts shortage
38%
38%
70%
70%
3%
3%
Quality
Quality
13%
13%
16%
16%
97%
97%
Resources
Resources
2%
2%
14%
14%
0%
0%
• Sites A & B did not track build time or
sources of delay
Initiative
What Will Improve the Part
What Will Improve the Part
Shortage Problem?
Shortage Problem?
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Part synchronization to assembly ops
Part synchronization to assembly ops
– Don’t start until all parts available
– Ensure all parts are available when needed
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Systemic factors
Systemic factors
– Planning
– Scheduling
– Supplier networks
– Long term agreements
Initiative
Part Synchronization
Part Synchronization
Supplier Kanban 80% of parts value MRP Kanban Monthly Batches MRP MRP Warehouse Assembly Plant Key:Initiative
Observations
Observations
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l Systemic attack on part synchronization Systemic attack on part synchronization yields major benefits to on time build
yields major benefits to on time build
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l Must have information to focus actionsMust have information to focus actions
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l Cycle time continues to be important metricCycle time continues to be important metric
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l Production synchronization with suppliers Production synchronization with suppliers requires steps beyond long term
requires steps beyond long term agreements and certified suppliers agreements and certified suppliers
