Download - Presentation at 7 th Annual Wildland Fire Safety Summit, Toronto, Ontario, Canada 19th July,2003
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THE SAFE AND ECONOMIC STRUCTURAL HEALTH MANAGEMENT OF AIRTANKER AND LEAD AIRCRAFT INVOLVED IN FIREBOMBING
OPERATIONS
Presentation at 7th Annual Wildland Fire Safety Summit, Toronto, Ontario, Canada
19th July,2003
Steve Hall (Celeris Aerospace Canada Inc.)Dick Perry (Sandia National Laboratory)
Joe Braun (Systems and Electronics Inc.)
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OVERVIEW Reasons for Structural Concerns Related to Aircraft Operating in the
Firebombing Role Potential causes of structural problems
Addressing the Structural Concerns Rationale behind the procedures and processes that need to be
implemented with particular reference to fatigue and damage tolerance Understanding the loads imposed on firebombing aircraft
Structural Health Management of Aircraft Involved in the Firebombing Role
Short and longer term issues related to the safe and economic use of these aircraft
Inspection, Maintenance and the Bottom Line Accumulating Knowledge Pending Activities Conclusions and Recommendations
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SUMMER 2002 WING FAILURES
C-130A Built 1957 21,900 hours total Both wings failed June 2002
PB4Y-2 Single Tail Liberator Built 1944/45 timeframe 8,200 Special Mission hours Failure one wing July 2002
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REASONS FOR CONCERN
Resulted in the formation of the Blue Ribbon Commission by the USDA/FS and BLM which reported in December 2002
Number of recommendations/observations including Many of the aircraft involved in the firebombing role were not
designed for this role Loads to which they have been subjected are largely unknown as is
their current structural health status There is a need to harmonize the inspection and maintenance of
firebombing aircraft with modern day certification approaches such as fatigue and damage tolerance
Approach to funding, contracts and the ongoing and modernization of the fleet needs to be reviewed
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ADVERSE OPERATIONAL IMPLICATIONS
C-130A and PB4Y-2 Fleets immediately grounded Loss of approx 10-12 Heavy Tankers
Major concerns about USDA/FS Beech Baron Lead Aircraft Immediate need for replacement?
Forest Service note that contracts will not be awarded to C-130A and PB4Y-2 aircraft
Heavy airtankers operating with a 15% reduction in payload for the 2003 fire season
Unanticipated expenses associated with additional inspection and maintenance actions
Delayed contract award and operational availability
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OVERVIEW OF FIREBOMBING AIRCRAFT CONFIGURATIONS AND OPERATIONS
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FIREBOMBING AIRCRAFT
Air Tankers 800 – 1,200 gallons Translates to
approximately 8,000 to 12,000 lbs
Heavy Air Tankers 2,200 – 3,000 gallons and
above Translates to approximately
22,000 to 30,000 lbs retardant
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FIREBOMBING AIRCRAFT (cont)
Lead Aircraft Initial Survey of Fire for
Escape Routes Guide Heavy Tankers in
over fire Ensure Fire Prevention
Officer has view of drop Spend far more time
over the fire than do the air tankers
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AIR TANKER CONFIGURATION
Scoop
Internal Tank
External Tank
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TYPES OF TANK
Constant Flow One pair doors Computer controlled Aperture changes to
ensure constant flow Consistent “Coverage
Level”
Sequenced Doors Two, four, eight or more Door sequence
automatically selected Release percentage of
load that is proportional to the number of doors
Coverage Level not as consistent
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TYPES OF LOAD
Retardant or Foam Pre-mixed or mixed on board Drop as a barrier to the fire
Water Dropping on the fire
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OPERATIONAL PROFILE AIR TANKERS
Transit to fire Depends on distance, if relatively close often below 2000 ft
AGL Holding pattern around the fire
Generally around 1,000 ft to 1,500ft around the fire Drop Zone
150 ft AGL (or 150ft parallel to terrain in mountainous drops) Airspeed around 110 – 120 knots
Flap often required (typically 50%, occasionally 100%) Want available power when retracted
Load, usually dropped in 50% increments, occasionally 100% Drop Time
Of the order of 4 -10 seconds depending on coverage level
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Potential Causes of Structural Problems
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SPECIAL MISSION AIRCRAFT
Aircraft that is operating in a role for which was not envisaged during its design
Firebombing Aircraft ILS/VOR Calibration Pipeline/Geological Survey Crop-Spraying Atmospheric Research (Hurricane Hunters)
Majority tend to operate in Low-level roles Low-level consistent use below 2,500 ft AGL Turbulent environment aircraft subject to an increased gust frequency Some roles involve increased manoeuvre spectrum for terrain avoidance
Note that even when an aircraft has been designed for the environment, care is required regarding the source of the design loads
Lots of data for low-level data is transit data and is not usually representative of consistent low-level operation
High-Level Role
Low-level Roles
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WHAT DO WE KNOW ABOUT SPECIAL MISSION SPECTRUM?
Generally very little Limited number of health monitoring programs
completed to define the loadsNRCC/IAR Circa Mid 1970’s - 1988Limited NASA Work (Reliability Issue)FAA Collecting Low-level data, yet to be collated
However, from the limited data available some initial trends have been identified which indicate an urgent need for further work
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LOADING MECHANISMS
Two mechanisms that have to be considered High Load Exceedance or Overstressing the aircraft
Over-g of the aircraft High Load at High Weight Concerns
Long-term impact of cyclic loading Fatigue and Damage Tolerance
Repetitions of cyclic loading and its accumulated impact A major focus of past analyses of special mission
aircraft has been the high load exceedance aspects Part of the picture and something of which we have to be
constantly vigilant However, it is by no means the full picture, nor the major
reason for the structural failures that have occurred
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IDENTIFYING HARSH OR UNUSUAL USAGE
Exceedances/Hour (Log)
G-Level
Increasing SeverityIncreasing Severity
1.0g
-ve Spectrum +ve Spectrum
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COMPARATIVE SEVERITY
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F-27 DATA – SAMPLE 003
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
-1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4
G-Level
Exc
eed
ance
s p
er H
ou
r
F-27 Total (003)
F-27 Heavy (003)
F-27 Light (003)
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F-27 DATA – SAMPLE 004
1.0E-02
1.0E-01
1.0E+00
1.0E+01
1.0E+02
-1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4
G-Level
Ex
ce
ed
an
ce
s p
er
Ho
ur
F-27 Total (004)
F-27 Heavy (004)
F-27 Light (004)
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FATIGUE CONCEPTS
Alt
ern
ati
ng
Str
es
s (
Sa
)
Number of Cycles (N)
Different Mean Stress Levels
(Sm)
Str
es
s
Time
Min Stress (Smin)
Mean Stress (Sm)
Max Stress (Smax)
Alt Stress (Sa)
R =Smin
Smax
Miner’s Cumulative Damage Law
1..........3
3
2
2
1
1 n
n
N
n
N
n
N
n
N
n
N1
Sa1
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MAIN OBSERVATIONS Aircraft in Low-level Special Mission Roles see a much more
severe spectrum than comparable aircraft operating in the roles for which they were originally designed
Inordinate amount of relatively low-level loads Much more turbulent environment More Manoeuvres
Control Aircraft Terrain avoidance
Some high loads, but generally the majority of the structural damage can be attributed to the low level loads
A large amount of accumulated world-wide flying in the original design role is a necessary, but not a sufficient condition for ongoing structural integrity in the special mission role
Acceleration of damage in critical areas Damage being sustained in previously unknown areas
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ADDRESSING THE STRUCTURAL CONCERNS
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SO WHAT? The previous slides have illustrated that the
limited data available suggests that from a cyclic loading perspective (fatigue) firebombing usage is more severe than many operational roles, including the roles for which the majority of the aircraft were designed
The next issue that has to be addressed is what are the implications of these loads for individual aircraft structures?
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EVALUATING THE SIGNIFICANCE
Identify areas in the structure that are likely to be adversely impacted by firebombing usage and assess exactly how they will respond
Structural Analysis/Certification terminology these are termed critical areas, Principal Structural Elements (PSE’s) or Structurally Significant Items (SSI’s)
To do this we need to understand the cyclic stresses experienced at each location
Load is what is applied, stress is how the structure responds Typically we measure loads Mechanism of translating these to stresses (Use of “Transfer Functions”)
Detail structural configuration
Evaluate the structural health at each location Where are we starting from, ie: what has happened in the past Where are we going, ie: based on the starting point how fast is future usage
consuming the “health” of the structure?
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COMPARISON ASW vs FIREBOMBING
Data from Grumman Tracker (S2) Canadian Forces ASW OMNR Firebombing (Undulating) West Coast Firebombing
(Mountainous) Assuming similar weights and
Stress/g of between 5ksi/g and 10ksi/g
Firebombing is approximately 1.8 to 2.0 times as severe as ASW
FIREBOMBING
MOUNTAINOUS
FIREBOMBING
MOUNTAINOUS
FIREBOMBING
UNDULATING
ASW OPERATIONS
ASW OPERATIONS
FIREBOMBING
UNDULATING
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CHALLENGES OF SPECIAL MISSION AIRCRAFT
Generally older aircraft May or may not be supported by the OEM or a type
certificate holder Frequently not supportive or consider it not cost-effective to
generate data for this role Liability/Risk issues
Engineering data is often limited Regular data collection and validation is not easy as aircraft
are frequently geographically dispersed Frequently not equipped with a data-bus that facilitates the
straightforward capture of many parameters
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HOW DO YOU GO ABOUT EVALUATING THE ONGOING STRUCTURAL HEALTH OF AN
AIRCRAFT?
What do you measure, what criteria do you use?
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ACTIONS INITIATED USDA/FS & Sandia Laboratory inspection base-lining program
Development of Structural Health Management Plans by some operators
Including generic and specific parameters
Instrumentation of a C-130A Aircraft and development of initial firebombing profiles
Sponsored by the FAA and TBM/IAR
Initial instrumentation and limited preliminary analysis of North American Based Airtankers
Sponsored by the USDA/FS and Sandia Laboratories 2003 – P2, P3, DC-7 and possibly CV-580 2004 – Additional aircraft
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BASELINE INSPECTION PROGRAM
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PURPOSE
Reduce risk of major structural failure One time for 2003 season Enhanced Inspection Program
Determine the condition of the fleet Basis for continuing program for long-term
airworthiness Standardization among contractors and types Identify best practices
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PROCESS
Documentation search Historical information OEM and other user documents
Site visits to all large air tanker contractors Inspection documentation Inspection practice Damage histories
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SANDIA FINDINGS Damage Tolerance Assessment
P-3US Navy missions most relevant to P-3CFull scale fatigue testing (P-3C, 2002-2003)
P-2VNo relevant data identified
C-54-DC, DC-6, DC-7SID on DC-6 only1992Based on service history
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SANDIA FINDINGS (cont)
Inspection Programs (AIPs) Wide variation in depth and detail of AIPs No FAA process for standardization or periodic
review Wide variation in use of NDI beyond visual
inspection
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SANDIA FINDINGS (cont)
Existing history data and inspection practice are less effective than true damage tolerance assessment as air tanker time builds in relation to prior mission time
Flight environment and loads data are essential elements of a damage tolerance based continuing airworthiness program, for both current and future air tankers
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IMPLEMENTING A STRUCTURAL HEALTH MONITORING PROGRAM
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Certified, Safe and
Economically Viable Aircraft
Inspection, Maintenance and Overhaul Intervals
Fatigue and Damage
Tolerance Analysis
Critical Area Identification
Previous Flight or Full-Scale Tests
Past Service History
Maintenance Records as
a Firebomber Aircraft Configuration and Model Variants
Loads Actually Experienced by the Aircraft in Critical
Areas
Critical Area Geometry Factors
Relevant Materials Data
Parameters to be Monitored
Recorders and Instrumentation
Operational Data Acquisition and
Validation
Data Analysis and Dissemination
Development of New Techniques
Depot LevelField Deployable
Structural Health Management Plan Considerations
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PROGRAM SCOPE Limited Survey and assume representative of fleet usage
Loads Environment Stress Survey (LESS) Most severe Safety Factors Finite Commitment
Repeat periodically to assess validity LESS plus limited Individual Aircraft Tracking (IAT) program
Representative IAT aircraft to confirm LESS data remains valid Safety Factors not as severe Ongoing commitment
Repeat LESS when significant change in usage occurs LESS program plus full IAT program
Generally subset of LESS parameters on IAT aircraft Least severe safety factors Ongoing commitment
Repeat LESS when significant change in usage occurs
Initially Required for Firebombing as “representative” usage may not exist
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SELECTING PARAMETERS
Principle # 1: Minimize parameters to be monitored
Even though cost of additional channels and sensors relatively cheap
Avoid “If we are not sure let’s monitor it syndrome” AKA “More data has to be better”
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IDENTIFYING PARAMETERS Requirements
New requirements Service History Testing
Use of Existing or Development of Transfer Functions Stress Analysis, Test Data, etc.
Durability/Reliability in Operational Environment If you cannot reliably measure it or if robust sensor cannot be installed, the
parameter is of little use Integration with aircraft systems
Avoid impact on critical systems or structure Do not want airworthiness or certification issues
EMI/EMC has to be considered Components themselves Installed in aircraft
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GENERIC vs SPECIFIC PARAMETERS Generic parameters are “universal” parameters that
characterize the phenomena being measured Vertical Centre-of-Gravity Acceleration (Nzcg)
Specific parameters are parameters which represent the actual response of the structure to the phenomena
Strain gauge readings measured at specific locations on a structure
Location specific Ideally, require as many generic parameters as
practicable Practice: Require a combination of both
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SIGNIFICANT PHASES OF FLIGHT?
LANDING
“HEAVY”TAXI/TAKE-OFF
“LIGHT”
“BOMBING RUN”
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DATA CAPTURE REQUIREMENTS
Taxi/Take-Off
HeavyBomb Run
Light Landing
C.G Acceleration X X X X XStrain Readings (?) X X X X X
Aircraft Weight X X X X XAircraft Configuration X XType of Drop (Full or Partial Salvo) XAltitude XAirspeed X X X X XFlap Position X X XDifferential Cabin pressure ? ? ? ? ?Sink Speed XTouch and Go X
Location X XTime Synchronization/Correlation X XMission Type (Ferry, Firebomb, etc.) XWeather Conditions XAmbient Temperature X
Item
Read or Derived from Aircraft
Instrumentation or Data Bus
Installed Sensors
Source Function
Manual or Automatic Meta Data Extraction
What you "want"
What you may need to interpret what you
"want"
What you may need to interpret what you
"want"
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HOW/WHERE WILL IT BE OBTAINED? For each parameter you need to know
Measured Direct reading? Computed on Aircraft or Post-Flight?
Constant Recording or Discrete Signal What triggers/toggles recording on/off?, eg:
Application of Aircraft Power Weight-on-Wheels Airspeed below a certain value for a certain time
Derived from data on Aircraft Bus Computed on Aircraft or Post-Flight?
Derived from Ground (Meta) Data Interrogation of hard-copy data from form? Interrogation of electronically stored data?
Will data be obtained from a central location or from geographically dispersed locations?
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POTENTIAL PARAMETERS Continuous
Airspeed Centre-of-Gravity
Acceleration (Nzcg) Roll acceleration Pressure Altitude Radar Altitude Flap Position Aileron Position Elevator Position Float Position ( Continuous
Flow)
Discrete Weight-on-wheels Firebomb door sequencing
(weight) Supplementary Data
Fuel Load (Average Fuel Burn rate)
Flying Hours Configuration
Expansion 4-8 channels to address type
related issues if required Probably with strain gauges
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O p e ra t io n a lB a s e # 1
O p e ra t io n a lB a s e # 2
O p e ra t io n a lB a s e # N
C e n t r a l P r o c e s s in gF a c i l i t y
E n g in e e r in gA n a ly s is
S t r u c t u ra lA n a l y s i s
C o r ro s io nA n a l y s i s
L i f e - C y c l eM a n a g e m e n t
I n s p e c t io n a n dM a in te n a n c e
O p e r a t o rF e e d b a c k
I n s p e c t io n sC o m p le te d
In s p e c t io n s /M a in te n a n c e
R e q u ire d
In s t r u m e n ta t i o nM a i n t e n a n c e a n d
S u p p o r t
“D a y - to -D a y ”M a n a g e m e n t
M e d iu m /L o n g -T e rm
M a n a g e m e n t
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SOURCES OF DATA ERROR
Hardware Faulty Recorders and or Sensors Sensor installation problems Incorrect recorder initialization procedures
Software Incorrect data downloading and/or transcription Incorrect configuration tracking
Universal implementation of fleet-wide modifications Inappropriate application of Fill-in data
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TYPES OF DATA ACQUISITION ERROR
Two general classifications Logical Errors - Errors that can easily be identified
as right or wrongRange checksEvent response frequency
Potential Errors - Errors which only become apparent over time and/or require detailed analysis by skilled personnelStrain gauge drift
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FINAL DATA VALIDATION
Confirming initial (logical error) checks performed at operational bases
Evaluating potential error checks Strain gauge drift
Over time, implicit need for historical data Have to compare like data, implicit need to track data by
configuration Tracking initialization readings a good first start
Statistical Validation Beware of self-fulfilling prophecy Look for change in usage
Value of Exceedance curves and other tools
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OPERATIONAL ENVIRONMENT
Primary requirement is to provide a minimal increase in operational workload
You will not get the data you require if: Acquisition equipment requires:
Too much hand holdingTakes too much time to download Is not straightforward to useCannot easily be maintained or supported
Benefits of collecting data you do not require!!!
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PRELIMINARY CHARACTERIZATION OF FIREBOMBING ROLETBM/IAR/FAA C-130A FLARE PROGRAM
(YUMA ARIZONA February, 2003)
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C-130A AIRCRAFT (3,000 gallon)
Flight Test at U.S Army Test Range in Yuma Arizona
End February 2003 Defined Profiles (No Fire)
Calibration Flights Typical Firebombing Terrain
Level and Mountainous Twelve Continuous
Parameters Accelerations Strains Control Positions
Eight Discrete Parameters
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REMOVABLE TANK INSTALLATION
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RECORDER HARDWARE
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CONTROL POSITIONS
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door closeddoor open
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door opendoor closed
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door closed
door open
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door closed
door open
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OPERATIONAL DATA ACQUISITION ACTIVITIES2003 FIRE SEASON
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OPERATIONAL ACTIVITIES - 2003
TBM DC-7B Tanker 66 Approx 30 hrs Operational
Data
IAR C-130A Tanker 31 (Spain) Approx 50 hrs Operational
Data
Minden Aircraft P2-V7 Tanker 55 (Final Stages Instrumentation)
Aero Union P3-A Tanker 55 (Final Stages Instrumentation)
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SEI CUMULATIVE FATIGUE RECORDER (CFR) MODEL A1002
The CFR Model A1002 made by SEI is capable of recording 24 analog signals, 16 digital signals and global positioning as an option
The analog signals will be 12 high level and 12 low level signals. The low level signals will be capable of accepting strain gauge type signals (millivolts).
The recorded flight data will be stored on a 32 megabyte PCMCIA card.
The weight of this unit is less than 3 pounds.
It is designed to DO-160 for environmental and EMI.
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AIRCRAFT DATA ACQUISITION PROCESSING AND TRACKING (ADAPT) (Secure Web-based Download and Analysis)
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WORLD-WIDE DATA MANAGEMENT AND ACCESS
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INSTALLATION REQUIREMENTS
Preliminary Aircraft Survey Three to four days
Production of Survey/Installation Report and approval by Local Regulatory Agencies (eg: FAA/FSDO)
One Week to ?????? Manufacture and Distribution of Installation Kits
Six to Eight weeks Initial Running of Wires and Equipment (Operator Personnel)
About one week of continuous effort Connection of equipment and validation of operation (SEI/Celeris Aerospace
Personnel) Connection of Sensors Continuity Checks etc. (approximately 1 day) Ground Calibration Checks (approximately 1 day) Flight Checks (approx 2 hours flying with some simulated drops using water) Training of Operational Crews on Data Upload System (approx 1 day, undertaken in
conjunction with calibration process
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= 422nZ + 454 ± 59 (95%) = 366nZ + 445 ± 49
(95%)
Zero-g Strain Calibration
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C-130A SPANISH DATA
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C-130A SPAIN (High G – Flaps Down – Global View)
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C-130A SPAIN (High G – Flaps Down – Detail View)
11500 12000 12500 13000TIME
0.5
1.0
1.5
2.0
2.5
-200.0
300.0
800.0
1300.0
1800.0
0.0
1000.0
2000.0
3000.0
4000.0
5000.0
NZ by TIME
STR.2 by TIME
ALTITUDE by TIME
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EXAMPLE WING LOCATIONS - TBM DC-7
Centre-Spar Close View Left (Port Side) Wing, Looking Aft
Up
Inboard
Strain Gauge Location
Vertical c.g and Roll Accelerations
Control Position transducers
Discrete Signals to delineate flight phases
Strain Gauges:
3 Wing Locations (Matching Left and Right
1 Horizontal Stabilizer
1 Vertical Stabilizer
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DC-7B CALIFORNIA FIRES(Steep Descent – High G Flaps Down)
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DC-7B CALIFORNIA FIRES(Two Sequential Drops – Global View)
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DC-7B CALIFORNIA FIRES(Two Sequential Drops – Detail View)
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P-3A INSTALLATION
Cumulative Fatigue Recorder and Synchro to Analogue Converter
Left Aileron Position Transducer (String-Pot)
Airspeed and Altitude Transducers (Interface with Aircraft Pitot-Static System)
Left Wing Lower spar Cap Strain Gauge (Looking Aft)
Up
Inboard
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LESSONS LEARNED - IMPLEMENTATION
Preferable to do the installation in the off-season Should be starting now for 2004 Funding for these type of activities can be challenging
Need for consistency in approval process Depending on experience of local regulatory authorities approval can take
anywhere from one to ten plus weeks Central area in regulatory agencies with expertize in the installation of structural
health monitoring systems Remote support capability for troubleshooting is essential
Take advantage of inherent remote support capabilities of Windows XP Regular Data downloading essential
Every one to two days when active on fire as large amounts of significant structural activity
Essential to make this a bullet proof and straightforward process with minimal data footprint (slower modem connection compressed files)
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LESSONS LEARNED – PRELIMINARY DATA
G-Levels limits particularly with flaps down are exceeded on a frequent basis
Appears to be during or after drop However, CORRESPONDING STRAIN/STRESS LEVELS ARE
NOT THAT HIGH G has traditionally been used as a proxy for strain Transport aircraft conservative but OK Firebombing where large instantaneous change in weight it may be
inappropriate For Firebombing harsh or unusual usage should be based on
combined G and strain criteria? Should ensure safe operation but minimize unnecessary in-field
inspections and or change-out of aircraft Better feel for this aspect once additional data has been
collected during the 2004 fire season
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OBSERVATIONS RELATED TO LONGER-TERM ISSUES
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THREE PRONGED APPROACH
ONGOING SAFE AND ECONOMIC
MANAGEMENT OF CURRENT FLEET
STRATEGIC FIREBOMBING MANAGEMENT
PLAN
(Ten Year Sliding Window)
REGULATORY AND CERTIFICATION
ISSUES
TRANSITIONING TO REPLACEMENT
AIRCRAFT
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FLEET REPLACEMENT Based on current financial and practical limitations
current fleet replacement is realistically five to seven and more likely ten years away
Implies have to address issues related to current aircraft as there is no “short-term” fix
Two Implications There is a need to monitor the existing fleet as it is going to
be around for some time Efforts devoted to doing this will not be wasted as the data
collected will both help to ensure ongoing safety and provide a basis of selection for future firebombing aircraft
Prior to conversion and usage
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REGULATORY AND CERTIFICATION ISSUES
Regulatory and Certification Authorities have to be involved in the process as ultimately they determine the airworthiness criteria against which the aircraft will be evaluated
Direct impact of their cost and economic viability
There are a number of issues which need to be addressed with the industry to ensure safe, economic and practical provision of firebombing services
Change Product Rule (CPR) Impact/Implications on future aircraft conversions
Pending NPRM on evaluation basis of operational aircraft over the next ten years Impact/Implications for existing firebombing fleet
Access to engineering and support data In the light of liability/risk concerns versus potential revenue streams Relevance of this data from an aging aircraft perspective
Agreed Firebombing Certification Methodology? Based on a recognition of the unique and challenging demands of this role
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TRANSITIONING TO REPLACEMENT AIRCRAFT
Fleet Replacement Suitable Aircraft
Capability to carry/deliver the retardant Evaluating the ability of the structure to perform in the firebombing
role Development of a firebombing specification ??
Economic Basis Investment in alternate aircraft Ongoing monitoring of firebombing aircraft Fatigue and Damage Tolerance Basis
Maintenance and Inspection Intervals Delivery and Payment Models
Significant re-thinking of these issues as it would appear that the costs associated with the Blue Ribbon panel recommendations are not compatible with the current levels of funding
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ADDITIONAL OBSERVATIONS Addressing all the issues related to the ongoing safe and economic operation of
firebombing aircraft is a task for which no one organization would appear to have sufficient resources
Although this environment is a competitive one, there are significant economic benefits to collaboration on issues that effect everyone
Common recorder usage Common data collection and validation Combined efforts for fatigue and damage tolerance analysis of similar aircraft types
Now that the USDA/FS and SNL have developed the Infrastructure they are prepared to let other organizations can take advantage of this infrastructure on a cost recovery basis
Cost-effective way of implementation that allows everybody to benefit from generic data and trends
Coordination of efforts and regular exchange of information between regulatory agencies, client organizations and operators
Wealth of experience distributed through a variety of forums Can a system of meetings and working groups be set-up to disseminate information and develop policies and
procedures that would be beneficial to all?
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THE MISSING LINKS
Predominantly focused on large airtankers Other aircraft involved in firebombing
operations may be just as critical as they all work in a similar environment Smaller multi-engine and single engine airtankers Lead Aircraft Spotter (Bird-dog?) aircraft Rotary Wing Aircraft
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PENDING ACTIVITIES Collect data from existing instrumented aircraft and hopefully instrument more
aircraft during the 2004 fire season Funding Provisions are a challenge – more reliance on inter-agency collaboration? These activities need to be commenced within the next month
Develop a consistent and coherent certification and operational monitoring mechanism in collaboration with regulatory agencies and operators
Make best use of resources Avoid frustration
Develop a certification and fatigue/damage tolerance template using data from the existing program
Confidence and consistency of approach Cost-Effective as approval of a plethora of approaches will not be required
Develop collaborative efforts with other North American and non North American Agencies
Benefits of accumulating data to characterize the firebombing role quicker Shared lessons learnt improve both safety and the cost-effectiveness of
implementation
98Systems & Electronics, Inc.SEI
CONCLUSIONS/RECOMMENDATIONS
There is an urgent safety and economic need to fully characterize the loads experienced in the firebombing role Existing Aircraft Develop specifications for future aircraft
Due to the variability of operation, individual aircraft (total fleet) tracking systems should be implemented as soon as possible
Initial data acquisition should be expanded to lead aircraft as soon as possible Appear to experience the most severe usage and yet are currently not monitored
Programs to assess how best lower capacity multi-engine aircraft, single engine aircraft and rotary wing aircraft can best be monitored should be explored as soon as possible
A consistent and coherent certification and evaluation mechanism should be developed between contracting agencies, regulatory agencies and operators as soon as practicable
Validation through a template based on analysis of one or more existing aircraft types
The establishment of a Strategic Firebombing Structural Health Management Plan (Rolling Ten Year Window) for the Acquisition and Ongoing Operation of all Fixed and Rotary-wing Aircraft Involved in Firebombing Roles is essential if the ongoing safe and economic operation of current and existing fleets is to be ensured
Reflect, current and future requirements together with associated funding levels It is hard to envisage how the approaches recommended by the Blue Ribbon panel as a consequence of the 2002 heavy airtanker accidents
can be implemented within the current funding structure
Inter-agency and International collaboration for the assessment of aircraft in the firebombing role will provide the quickest and most-cost-effective method of addressing the many common challenges that are faced by all agencies using aircraft in this role
99Systems & Electronics, Inc.SEI
ACKNOWLEDGEMENTS TBM, IAR who have initiated and supported a lot of this recent
work Woody Grantham/Fritz Wester (IAR) Norm Stubbs (TBM)
FAA, USDA/FS and Sandia Laboratories for their ongoing support of the recent work
John Howford, Tom Defiore, Carl Gray, Todd Martin and Steve Edgar of FAA
Tony Kern and Ron Livingston of USDA/FS
Staff members at Celeris Aerospace and SEI who have established an infrastructure for structural health monitoring of heavy airtankers and lead aircraft in an incredibly short time-frame
100Systems & Electronics, Inc.SEI
CONTACTING THE PRESENTER
Celeris Aerospace Canada Inc.880 Taylor Creek Drive
Orleans, Ontario
CANADA, K1C 1T1
Tel: (613) 837-1161
FAX: (613) 834-6420
InternetSteve Hall - [email protected]
Webpage - http://www.celeris.ca