Design of a System for Aircraft Fuselage Inspection
Rui Filipe Fernandes
Kevin Keller
Manual Inspection
Automated Inspection
Before
jchadwickco.com
Jeffrey Robbins
Fatigue Damage
mechanicsupport.blogspot.com
Crack
After
aerospacetestinginternational.com
Computer Aided Detection
Reduce Inspection Time
Improve Crack Detection
Reduce Maintenance Cost
gasolinealleyantiques.com
Faculty Advisor
Dr. Lance Sherry
Sponsor
Integrity Applications Incorporated
Agenda
Context
• Aging Aircraft & Maintenance
• Current Fuselage Inspection Process
• Stakeholder Analysis
• Problem and Need
Concept Of Operations
Method of Analysis
Project Plan
Design of a System for Aircraft Fuselage Inspection
2
Context: Aging Aircraft & Maintenance
Aircraft Age Statistics
Min: 5.1 years
Mean: 10.6 years
Max: 24.9 years
airsafe.com
Average Aircraft Age Continues to Increase
Design of a System for Aircraft Fuselage Inspection
3
Context: Aging Aircraft & Maintenance
Increasing Average Age
Rank
Carrier
Average
Age
4
US Airways
14.7
5
Southwest
14.6
6
United
13.7
International Air Transport Association
Bloomberg
iata.org
bloomberg.com
Domestic Carriers among the oldest fleets
Design of a System for Aircraft Fuselage Inspection
4
Context: Aging Aircraft & Maintenance
Widespread Fatigue Damage
Widespread fatigue damage (WFD) is age-related structural fatigue cracking
iata.org
travelpulse.com
WFD Leading to Aircraft Retirement
Design of a System for Aircraft Fuselage Inspection
5
Context: Aging Aircraft & Maintenance
Aloha Airlines Flight 243
April 28, 1988, Boeing 737-200
lessonslearned.faa.gov
lessonslearned.faa.gov
Missing fuselage section caused by
failure of lap joint at stringer S-10L
Improved Maintenance Required
Design of a System for Aircraft Fuselage Inspection
6
Context: Aging Aircraft & Maintenance
Southwest Airlines Flight 812
Emergency Airworthiness Directive
AD 2011-08-51
136 Aircraft Inspected:
4 Found With Cracks Around 1 Rivet
1 Found With Cracks Around 2 Rivets
40,000 – 45,000 Total Cycles
ntsb.gov
April 1, 2011, Boeing 737-300
Preventative Maintenance Failed to Detect Indicators of Fatigue
Design of a System for Aircraft Fuselage Inspection
7
Context: Aging Aircraft & Maintenance
Deterioration
Factors that contribute to aircraft
deterioration include:
• Inflight vibrations
• Number of takeoffs and landings
• Fuselage pressurization cycles
30,000 ft. (4.38 psi)
newsweek.com
Fatigue Caused by Repeated Pressurization Cycles
Design of a System for Aircraft Fuselage Inspection
8
Context: Aging Aircraft & Maintenance
Fuselage Pressurization Cycles
engineeringtoolbox.com
Stress From Change in Pressure Leads to Structural Fatigue
Design of a System for Aircraft Fuselage Inspection
9
Context: Aging Aircraft & Preventative Maintenance
Scheduled Aircraft Maintenance Programs
Inspection Type
Time Between Inspections
Number of Man Hours Required
Time to Complete
A
125 flight hours
or 200–300 cycles
20–50 man-hours
Overnight
B
Approximately every 6 months
120–150 man-hours
1-3 Days
C
Approximately every
20–24 months
Up to 6,000 man-hours
1–2 weeks
D
Approximately every 6 years
Up to 50,000 man-hours
2 Months
faa.gov
Maintenance Intervals, A Delicate Balance of Risk and Cost
Design of a System for Aircraft Fuselage Inspection
10
Context: Aging Aircraft & Maintenance
Median Crack Growth Curve
Crack Length
Time of Inspection
Critical Crack Length
Earliest Expected
Cracking
Latest Expected
Cracking
Median crack growth curve
Time
Yang JN, Manning SD (1990)
Stochastic Crack Growth Analysis Methodologies For Metallic Structures
Minimize Number of Cracks Occurring Before Inspection
Design of a System for Aircraft Fuselage Inspection
11
Crack Length
Context: Aging Aircraft & Maintenance
Distribution of Time to Critical Crack Length
Time of Inspection
Probability of
cracks occurring
BEFORE scheduled
Maintenance
Distribution of Time to
Critical Crack Length
Critical Crack Length
Time
Yang JN, Manning SD (1990)
Stochastic Crack Growth Analysis Methodologies For Metallic Structures
Minimize Probability of Cracks Occurring Before Inspection
Design of a System for Aircraft Fuselage Inspection
12
Crack Length
Context: Aging Aircraft & Maintenance
Distribution of the Crack Length
Probability of crack growth
beyond critical length
Critical Crack Length
Distribution of the
crack length
Time
Time of Inspection
Yang JN, Manning SD (1990)
Stochastic Crack Growth Analysis Methodologies For Metallic Structures
Minimize Crack Growth Beyond Critical Length
Design of a System for Aircraft Fuselage Inspection
13
Crack Length
Context: Aging Aircraft & Maintenance
Stochastic Crack Growth Model
Probability of
cracks occurring
BEFORE scheduled
Maintenance
Probability of crack growth
beyond critical length
Distribution of Time to
Critical Crack Length
Critical Crack Length
Earliest Expected
Cracking
Latest Expected
Cracking
Distribution of the
crack length
Median crack growth curve
Time
Time of Inspection
Yang JN, Manning SD (1990)
Stochastic Crack Growth Analysis Methodologies For Metallic Structures
Early Crack Detection Can Minimize Corrective Maintenance
Design of a System for Aircraft Fuselage Inspection
14
Context: Aging Aircraft & Maintenance
Stochastic Crack Growth Model
Yang JN, Manning SD (1990)
Stochastic Crack Growth Analysis Methodologies For Metallic Structures
The inspection schedule is chosen such that the probability of crack
to grow beyond the critical crack size is less than 1 in 10,000,000
Taghipour, S., Banjevic, D., Jardine, A. K. S., “Periodic inspection optimization model for a complex repairable system”, Reliability Engineering and System Safety, Vol 95, 2010, Pg 944-952
Design of a System for Aircraft Fuselage Inspection
15
Context: Aging Aircraft & Corrective Maintenance
Airworthiness Directive (AD)
Airworthiness Directives are legally enforceable regulations
issued by the Federal Aviation Administration (FAA) in accordance
with 14 CFR part 39 to correct an unsafe condition in a product
When Does FAA Issue Airworthiness Directives?
When it finds an unsafe condition exists in the product and the condition is likely
to exist or develop in other products of the same type design
faa.gov
Corrective Maintenance is Disruptive to Airlines
and Results in Unplanned Revenue Loss
Design of a System for Aircraft Fuselage Inspection
16
Context: Aging Aircraft & Maintenance
Title 14 of the Code of Federal Regulations (CFR)
Changes in maintenance procedure
is regulated by the FAA
faa.gov
Inspection Process Governed by Title 14 (CFR)
Design of a System for Aircraft Fuselage Inspection
17
Context: Current Fuselage Inspection Process
Visual Inspection Process
• Job Cards Used For Every Component
• Many Human Factors/Prone to Errors
• 41.8% detected
• 14.1% type 1 error (Misdiagnosed)
• 43.7% type 2 error (Missed Detection)
• Non-Destructive Inspection (NDI)
methods used to assess marked regions
VISUAL INSPECTION RESEARCH PROJECT REPORT ON BENCHMARK INSPECTIONS
FAA Aging Aircraft NDI Validation Center
Inspection Process Begins with Visual Inspection
Design of a System for Aircraft Fuselage Inspection
18
Context: Current Fuselage Inspection Process
Representative Regions of Aircraft
FAA Aging Aircraft NDI Validation Center Report
JC 501
Midsection Floor
JC 502
Main Landing Gear Support
JC 503
Midsection Crown (Internal)
JC 504
Galley Doors (Internal)
JC 505
Rear Bilge (External)
JC 506
Left Forward Upper Lobe
JC 507
Left Forward Cargo Compartment
JC 508/509
Upper and Lower Rear Bulkhead Y-Ring
JC 510
Nose Wheel Well Forward Bulkhead
JC 511
Lap-Splice Panels
ntl.bts.gov
Representative Regions Require Different Inspection Techniques
Design of a System for Aircraft Fuselage Inspection
19
Context: Current Fuselage Inspection Process
Current Visual Inspection Process
Inspection Time of Lap-Splice Panels (Minutes)
Gamma
Shape 5.008
Scale 9.652
N
12
6
Frequency
5
4
3
2
1
0
20
45
70
95
Inspection Time (Minutes)
VISUAL INSPECTION RESEARCH PROJECT REPORT ON BENCHMARK INSPECTIONS
FAA Aging Aircraft NDI Validation Center
Inspection Process Modeled In Simulation
Design of a System for Aircraft Fuselage Inspection
20
Context: Stakeholder Analysis
Interactions, Tensions and Gap
Design of a System for Aircraft Fuselage Inspection
21
Context: Problem and Need
Issues
Problem
Current
Inspection
Process
Consequences
Time
Heavy D Check Inspection Process
Requires up to 2 months to Complete
Aircraft maintenance/repair 12-15%
of total airline annual expenditures
Cost
In 2013, 3.5 million flight cycles logged
over 2,660 aircraft
Average $2,652 per flight cycle
Amounts to $9.4 billion total
Quality
43.7% Type 2 Error (Missed Detection)
11 Airworthiness Directives Issued to
Address Fuselage Cracking
Solutions
Need
Improved
Inspection
Process
Benefits
Reduce Time Required for Inspections
Decreased Inspection Costs
Early Detection of Structural Fatigue
Improved Scheduling of Preventive
Maintenance / Minimize Corrective
Maintenance Required
Reduce Human Error
Improved Crack Detection Capabilities
Win-Win: New Technology Introduced to Inspection Process
Design of a System for Aircraft Fuselage Inspection
22
Agenda
Context
Concept of Operations
• Operational Scenario
• Design Alternatives
• System and Design Requirements
• Automated Inspection System IDEF.0
Method of Analysis
Project Plan
Design of a System for Aircraft Fuselage Inspection
23
Concept of Operations: Operational Scenario
Levels of Human Involvement
Inspection Method
2 - Enhanced
1 – Manual
ntl.bts.gov
aviationpros.com
aviationpros.com
3 - Autonomous
ConOps Introduces New Technology to Inspection Process
Design of a System for Aircraft Fuselage Inspection
24
Concept of Operations: Operational Scenario
Non-Contact Delivery Method
Synthetic Aperture
Imaging Device
Track
Potential Implementation of Synthetic Aperture Imaging Technology
Design of a System for Aircraft Fuselage Inspection
25
Concept of Operations: Design Alternatives
Exterior vs. Interior Surfaces
Exterior Surfaces
Interior surfaces
Human Visual
Human Visual
Human Remote Visual
Human Enhanced Visual
Human Enhanced Visual
Robotic Crawler*
Non-Contact
Automated Scan*
* Utilizes Image Processing Software
Limitations of Delivery Method Based on Region of Aircraft
Design of a System for Aircraft Fuselage Inspection
26
Concept of Operations: Design Alternatives
Benefits by Category
Inspection
Method
Time
Cost
Quality
Visual
Visual Inspection time
Documentation time
Hourly wage of inspectors
Training Cost
Cost of Human Errors
Limited by human eyesight
Prone to human error
Human decision making only
Enhanced
Visual
Increased Inspection Time
Imaging Time
Evaluation Time
Documentation Time
Hourly wage of inspectors
Training/certification
Maintenance Cost
Cost of Human Errors
Improved by computer
aided decision making
Interpretation/
Evaluation of data prone to
human errors
Automated
Faster Inspection Time
Imaging Time
Software Processing
Time
Acquisition/Development
Cost
Installation Cost
Training Cost
Maintenance Cost
Software for image
processing reduces
errors and eliminates
dependence on human
decision making
PRO CON
Design of a System for Aircraft Fuselage Inspection
27
Context: System Requirements
Mission and Functional Requirements
Context:
System Requirements
M.1 The system shall reduce the airframe maintenance cost per flight hour of an aircraft by 5%
Mission & Functional Requirements
F.1. The system shall cost no more than $X to operate annually
F.2. The system shall accrue no more than $X in Type 1 errors annually
F.3. The system shall require an initial investment of no more than $X
F.4. The system shall process captured images at a rate of X m2 per Y seconds
M.2 The system shall detect cracks in the airframe of aircraft both visible, and not visible, by a human
inspector
F.1. The system shall detect cracks with a volume exceeding X mm3
F.2. The system shall have a Type 2 error rate of no more than X%
F.3. The system shall distinguish between cracks and pre-built parts of the aircraft
F.4. The system shall capture an image of the airframe of the aircraft of dimensions X meters by Y meters
without repositioning
M.3 The system shall reduce the variance of the airframe inspection process by X labor-hours
F.1. The system shall maintain the upper bound of a complete visual inspection at no more than X laborhours
F.2. The system shall reduce the variance of the visual inspection process by X labor-hours
M.4 The system shall allow aircraft to meet Federal Aviation Administration airworthiness standards
Design of a System for Aircraft Fuselage Inspection
28
Context: Non-Functional Requirements
Non-Functional Requirements
Maintainability
1. The system shall produce traceable error codes upon malfunction.
2. The system shall allow the replacement of individual parts.
Reliability
1. The system shall experience no more than X system failures per month.
2. The system shall require no more than X hours of preventative maintenance per month.
Usability
1. The system shall require no more than 40 hours of training for technician certification.
Design of a System for Aircraft Fuselage Inspection
29
Concept of Operations: Design Requirements
Design Requirements
Enhanced Visual (Handheld)
D.1 The system shall weigh no more than X lbs.
D.2 The system shall accurately scan from a distance of up to X m.
Robotic Automated Inspection System
D.1 The system shall inspect at a rate of X cm3/s.
D.2 The system shall support autonomous function.
D.3 The system shall accept initial input from an operator.
D.4 The system shall utilize integrated software.
D.5 The system shall store the location of airframe problem areas.
Design of a System for Aircraft Fuselage Inspection
30
Concept of Operations: Automated Inspection System IDEF.0
Design of a System for Aircraft Fuselage Inspection
31
Agenda
Context
Operational Concept/Approach
Method of Analysis
• Stochastic Simulation
• Model Boundaries & Simulation Inputs/Outputs
• Simulation Requirements
• Simulation of Visual Inspection By Airframe Region
• Case Study Variables & Assumptions
• Validation
• Design of Experiments
Project Plan
Design of a System for Aircraft Fuselage Inspection
32
Method of Analysis: Stochastic Simulation
Model Boundaries and Simulation Inputs/Outputs
Uninspected
aircraft
Aircraft
Maintenance
Simulation
Manual
• Human
• Handheld
Automated
• Visual or thermal
• Track or crawler
Inputs
•
•
Inspected
aircraft
• Time per inspection
• Inspection & Section
• Cost per inspection
• Labor hours
• Implementing alt.
• Quality per inspection
• Type 1 & 2 errors
Outputs
What design alternatives are utilized
Where design alternative are utilized
•
•
•
•
•
Overall time for inspection
Time per section
Cracks detected per section
Type 1 errors per section
Type 2 errors per section
Design of a System for Aircraft Fuselage Inspection
33
Method of Analysis: Stochastic Simulation
Simulation Requirements
Simulation Requirements
The simulation shall break down the aircraft into ten sections, each having its own queue
The simulation shall support multiple inspectors processing multiple sections
The simulation shall assign a set number of cracks to each section of the aircraft
The simulation shall terminate upon the inspection of all ten sections of the aircraft
The simulation shall collect statistics on total time required for inspection
The simulation shall collect statistics on total time to complete each section
The simulation shall collect statistics on cracks detected per section
The simulation shall collect statistics on crack type one errors
Mark a crack where one would not register with an NDT
The simulation shall collect statistics on crack type two errors
Fail to mark a crack that exists
Design of a System for Aircraft Fuselage Inspection
34
Method of Analysis: Stochastic Simulation
Visual Inspection By Airframe Region
Initialization
Statistics
Process
Design of a System for Aircraft Fuselage Inspection
35
Method of Analysis: Stochastic Simulation
Initialization
Assignments
Manual / Automated
(binary)
Process Restrictions
(binary)
Process Distributions
(minutes)
Crack Detection Rate (%)
Type 1 Error Rate (%)
Type 2 Error Rate (%)
Design of a System for Aircraft Fuselage Inspection
36
Method of Analysis: Stochastic Simulation
Process
Design of a System for Aircraft Fuselage Inspection
37
Method of Analysis: Stochastic Simulation
Statistics
Design of a System for Aircraft Fuselage Inspection
38
Method of Analysis: Stochastic Simulation
Distributions At a Glance
VISUAL INSPECTION RESEARCH PROJECT REPORT ON BENCHMARK INSPECTIONS
FAA Aging Aircraft NDI Validation Center
Design of a System for Aircraft Fuselage Inspection
39
Method of Analysis
Design of Experiments
Inputs
Outputs
Run
Internal
/
External
Technology
Delivery
Method
Type
One
Error
Rate
Type
Two
Error
Rate
1
Internal
Human
--
%
%
External
Human
--
Internal
Human
--
External
Thermographic
Crawler
Internal
Synthetic Aperture
Handheld
External
Thermographic
Crawler
2
3
Inspection
Cost of
Time
Inspection
Hours
Dollars
…
Design of a System for Aircraft Fuselage Inspection
40
Simulation Preliminary Results
Sample Output (Time per Process)
Section
Minutes
Design of a System for Aircraft Fuselage Inspection
Half-Width
41
As-Is Simulation Preliminary Results
Validation (Expected vs Simulation)
Section
Actual (mins)
Simulated (mins)
Diff (mins)
% err
1
122
116.47
-5.53
-4.53
2
28
27.83
-0.17
-0.61
3
75
75.38
0.38
0.51
4
68
67.71
-0.29
-0.43
5
37
36.1
-0.9
-2.43
6
104
105.64
1.64
1.58
7
95
100.23
5.23
5.51
8
35
34.68
-0.32
-0.91
9
16
15.2
-0.8
-5.00
10
48
49.56
1.56
3.25
Actual Total (mins)
Sim Total (mins)
Diff (mins)
% err
628
628.81
Sim Half Width
(mins)
0.81
<0.1%
6.18
Design of a System for Aircraft Fuselage Inspection
42
Agenda
Context
Operational Concept/Approach
Method of Analysis
Project Plan
• WBS/Schedule
• Critical Path/Project Risks
• Budget/Performance
Design of a System for Aircraft Fuselage Inspection
43
Project Plan: Work Breakdown Schedule
Aircraft
Inspection
Project
1.1
Management
1.2
Research
1.2.1
1.3
CONOPS
1.4
Originating
Requirements
1.3.1
Context Analysis
1.4.1
Stakeholders
Requirements
1.2.2
Kick-off
Presenation
Research
1.3.2
Stakeholder
Analysis
1.4.2
Performance
Requirements
1.2.3
Team Research
1.3.3
Problem
Statement
1.4.3
Application
Requirements
1.3.4
Need Statement
1.1.5
Meetings with
Professors
1.5
Design
Alternatives
1.6.1
Initial
Simulation
Analysis
1.7
Test
1.8
Design
1.13
Competitions
1.12.2
Proposal
1.9.3
Simulation
Programming
1.11.3
Brief 3
1.13.3
UVA
1.4.4
Analysis of
Requirements
1.11.4
Brief 4
1.13.4
West Point
1.3.5
Operational
Concept
1.4.5
Qualify the
qualification
system
1.11.5
Faculty
Presentation
1.1.6
Individual
Meetings
1.3.6
System
Boundary
1.4.6
Obtain Approval
of Syst.
Documentation
1.11.6
Final Fall
Presentation
1.1.7
1.3.7
System
Objectives
1.4.7
Functional
Requirements
1.3.8
Statement of
Work
1.4.8
Design
Requirements
1.1.3
Email
Communication
s
1.1.4
Sponsor
Meetings
Team Meetings
1.1.8
WBS Upkeep
1.3.9
Budget
1.3.10
Project Risks
1.8.2
Refine DoE
1.12
Documentation
1.11.2
Brief 2
1.6.2
Sensitivity
Analysis
1.9.1
Simulation
Requirements
1.11
Presentations
1.9.2
Simulation
Design
1.1.2
Acc.Summary
1.8.1
Initial Design of
Experiment
1.10
Testing
1.12.1
Preliminary
Project Plan
Lead Initial
Research
1.7.1
Verification and
Validation
1.9
Simulation
1.11.1
Brief 1
1.1.1
Timesheets
1.5.1
Develop Design
Alternatives
1.6
Analysis
Simulation Debugging
1.13.1
Conference
Paper
1.13.2
Poster
1.1 Management
1.2 Research
1.3 CONOPS
1.4 Originating Requirements
1.5 Design Alternatives
1.6 Analysis
1.7 Test (V/V)
1.8 Design
1.9 Simulation
1.10 Testing (Simulation)
1.11 Competitions
Design of a System for Aircraft Fuselage Inspection
44
Project Plan: Critical Path
Critical Path
1.4 Originating Requirements
1.5 Design Alternatives
1.6 Analysis
1.7 Test
1.8 Design
1.9 Simulation
1.10 Testing
Design of a System for Aircraft Fuselage Inspection
45
Project Plan: Project Risks
Critical Tasks
Acquire technology specifications
Foreseeable Risk
Sponsor does not share information
from Sponsor
Acquire data on inspection tasks
Mitigation Routes
Alter design to trade off analysis of
crack inspection methods
Data is not available/accessible
Use reasonable estimates based on
available data
Quantify requirements
Data is not available/accessible
Use reasonable estimates based on
available data
Sensitivity Analysis
Data does not correspond to industry
Ensure simulation is built correctly,
practices
may need further development
Design of a System for Aircraft Fuselage Inspection
46
Project Plan: Budget/Performance
31-Aug
1
$913.40
$608.93
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$86.99
$0.00
$0.00
40
$1,739.80
7-Sep
2
$1,130.87
$565.44
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$86.99
$0.00
$0.00
50
$2,174.75
14-Sep
3
$1,652.81
$565.44
$260.97
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$0.00
$1,000.39
$0.00
$0.00
60
$2,609.70
21-Sep
4
$598.06
$521.94
$391.46
$0.00
$0.00
$0.00
$0.00
$521.94
$217.48
$0.00
$391.46
$0.00
$0.00
60
$2,609.70
Cumulative Planned Value (PV) $1,739.80
$3,914.55
$6,524.25
$9,133.95
WBS
Task Name
TBC
1
2
3
4
5
6
7
8
9
10
11
12
13
Management
Research
CONOPS
Originating Requirements
Design Alternatives
Analysis
Test
Design
Simulation
Testing
Presentations
Documantation
Competitions
Total Budgeted Hours
Total Budgeted Cost
$6,100.17
$3,958.05
$1,652.81
$391.46
$217.48
$0.00
$0.00
$565.44
$1,261.36
$0.00
$3,349.12
$826.41
$0.00
2,125
$92,426.88
Cost Variance (CV = EV - AC)
Schedule Variance (SV = EV - PV)
Cost Performance Index (CPI = EV/AC)
Schedule Performance Index (SPI = EV/PV)
Estimated Cost at Completion (EAC)
-$518.68
-649.16
0.68
0.63
$136,382.63
-$1,075.78
-1597.72
0.68
0.59
$135,343.48
-$463.95
-115.99
0.93
0.98
$99,118.41
$466.03
846.61
1.05
1.09
$88,111.11
$1,672.74
2118.56
1.14
1.18
$81,273.83
$2,065.16
1858.56
1.15
1.13
$80,653.05
$1,808.75
819.24
1.11
1.05
$83,025.53
$2,674.24
553.86
1.15
1.03
$80,654.84
Hourly Rate: $43.50/hr
Design of a System for Aircraft Fuselage Inspection
47
Project Plan: Budget/Performance
Earned Value Weeks 1-38
Design of a System for Aircraft Fuselage Inspection
48
Project Plan: Budget/Performance
Earned Value Weeks 1-11
Design of a System for Aircraft Fuselage Inspection
49
Project Plan: Budget/Performance
CPI/SPI Weeks 1-11
Design of a System for Aircraft Fuselage Inspection
50
Future Work
Now
•
•
•
•
•
•
Determine attributes of design alternatives
Complete design of experiment
Sensitivity analysis
Quantify requirements
Utility - cost analysis
Conclusions
February
2016
Design of a System for Aircraft Fuselage Inspection
51
Design of a System for Aircraft Fuselage Inspection
52
Utility Hierarchy
Utility
Time (-)
Non-Functional
Quality
Maintainability (+)
Type 1 Error Rate (-)
Reliability (+)
Type 2 Error Rate (-)
(+) – Higher is better
(-) – Lower is better
Design of a System for Aircraft Fuselage Inspection
53
IDEF0 Analyze Data
Design of a System for Aircraft Fuselage Inspection
54
Arena Total Time
Design of a System for Aircraft Fuselage
Inspection
55
Project Plan: Budget/Performance
United States Department of Labor Bureau of Labor Statistics
Occupational Outlook Handbook
Occupation
2012 Median Pay
Aerospace-Engineers
$49.07/hr
Industrial-Engineers
$37.92/hr
http://www.bls.gov/ooh/architecture-and-engineering/aerospace-engineers.htm
http://www.bls.gov/ooh/architecture-and-engineering/industrial-engineers.htm
Average: $43.50/hr
Design of a System for Aircraft Fuselage Inspection
56
Concept of Operations: Design Alternatives
Design Alternatives
Technology
Description
Thermographic
Imaging
Heats area 1-2 degrees,
algorithm determines if
problematic
Synthetic
Aperture
Imaging
Captures 2-D images at
different angles to create
a 3-D image
Contact
Non-Contact
Contact
Non-Contact
Delivery
Method
Description
Level of Human
Involvement
Robotic Crawler
Travels along outside of
aircraft, scans
designated areas.
Autonomous
Synthetic Aperture,
Thermographic
Robotic Arm
Utilizes track to move
around.
Autonomous
Synthetic Aperture
Handheld
Scanner carried by
inspector
Enhanced
Synthetic Aperture
Design of a System for Aircraft Fuselage Inspection
Applicable Technology
57