Air Platforms Safety and Affordability Technologies

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Air Platforms Safety and Affordability
Technologies
Main Rotor Blade Erosion Coatings
Executing Code ONR Code 35 EC Manager Ms.
Malinda Pagett, ONR Code 352 Product Manager Dr.
David Shifler, ONR Code 332 Product Manager Dr.
David Haas, ONR Code 352/NSWC Carderock
The 2007 Naval ST Partnership Conference is
presented by NDIA with technical support from
ONR DISTRIBUTION STATEMENT A Approved for
public release distribution is unlimited.
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EPE-FY09-03 Air Platforms Safety and
Affordability Technologies

• ST funding is critical for the safe operation
  and availability of existing aviation assets.
• The proposed EC focuses on two ST investments
• Advanced Helicopter Main Rotor Blade Erosion
  Coatings
• Adaptive Expert System for Autonomous Detection
  of Aviation Mishap Leading Indicators

• EC Metrics
• 15 - 20 reduction in H-53 rotor blade returns
  to the depot from a current baseline of 900 per
  year (approx 5.6M) 10x increase in rotor blade
  life from 1,200 to 12,000 hrs
• 25 reduction in Class A/B mishaps (e.g., would
  equate to reduction of 36 Class A mishaps FY02-06)

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Enabling Capability Problem Definition

• Main Rotor Blade Erosion Coating
• The leading edge degradation of rotor blades by
  sand erosion has become one of the largest
  logistics and maintenance burdens.
• Rotor blade life reduced to 1,200 hours
• Demand rates in 2004 52M (AH-64) 100M
  (UH-60) 35M (CH-47)
• Rain also degrades rotor blades.
• Ti leading edge protection exhibits a Corona
  effect which makes helicopters an easy target
  from small arms fire.
• Adaptive Expert System
• Extended plateau in DON aviation mishap rates
• Mishap rates relatively stagnant for past 20
  years
• Human factors are approximately 80 of mishap
  related causal factors.
• DoD mandated reduction in number of aviation
  mishaps will not accept status quo SECDEF
  memo 22 Jun 06 (DON Aviation FY06- 24 Class A
  mishaps, 25 fatalities, 16 acft destroyed)

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Enabling Capability Selection

• Rationale for Technology Selection
• Current main rotor system blades protection
  (tapes and paints) exhibited widespread rain
  erosion to substrate in less than 41 minutes.
• Military Flight Operations Quality Assurance
  (MFOQA) is a principal mishap reduction
  initiative that will generate data quantities
  impractical for comprehensive screening by SMEs.
  Advanced automated analytical tools are required
  to maximize detection of mishap leading
  indicators for corrective action prior to mishap.
• Why Now?
• Rotor and engine technologies identified in
  NAVAIR Rotorcraft ST Workshop as high priority
  items.
• To coincide with technology insertion opportunity
  for transition of Adaptive Expert System
  technology module to Phase 2 MFOQA program (PMA
  209) in FY13.

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Advanced Helicopter Main Rotor Blade Erosion
Coatings

• Technical Description
• Technical evaluation of material coatings for
  erosion control on rotor blade leading edges.
• Exit criteria
• Abrasion resistance increase by 50.
• Lifespan increase from 1,200 hrs in erosive
  environment to 12,000 hrs

• BAA Areas of Interest
• Integration with rotor blades in existing /
  future rotary aircraft
• Mass balancing (c.g., mass moments of inertia, )
• Aerodynamics (surface finish, )
• Blade section properties (flap / twist stiffness,
  )
• Strain compatibility with blade
• Foreign Object Damage (FOD) resistance
• Deicing and resistance to lightening strike
• Material qualification
• Material thermal mechanical properties, sand /
  rain erosion rate resistance to FOD, Solvents,
  Oils, Fuel, UV light, Fungus, Reparability
• Segment of candidate materials leading edge in
  whirling arm rig for sand / rain erosion and
  impact resistance tests
• Ground and flight tests Main rotor blades
  fitted with candidate materials

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Advanced Helicopter Main Rotor Blade Erosion
Coating Current Solutions

• 3M tape does not provide an adequate solution.
• High volume-metric sand erosion rate
• Rain drop impact creates tear quickly
• With combined sand and rain erosion, damage
  caused by prior sand erosion propagates fast
  under severe water hammer stress

• Polymeric coating offers 4x improvement over 3M
  tapes, but still not robust.
• Easy to apply and repair
• Good for sand erosion resistance as soft polymer
  absorbs impact energy by large elastic
  deformation
• However, shear stress from rain drop impact
  creates further damage and a longer term erosion
  protection solution is still desired

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Adaptive Expert System for Autonomous Detection
of Aviation Mishap Leading Indicators

• Technical Description
• Development of an Adaptive Expert System to
  automatically and rapidly analyze aircrew
  performance (1M flight hours annually) to detect
  human factors related mishap leading indicators.
  A critical element is determining if a successful
  feedback mechanism can be developed so the expert
  system adaptation process can take place. A new
  technique using anomaly detection and
  corroboration will be developed for use, in lieu
  of current feedback methods used with artificial
  neural networks (i.e., error minimization),
  because it more closely replicates the human
  reasoning process.
• Exit criteria
• Acceptance of results by Subject Matter Experts
  80 agreement between automated and manual
  methods
• Correctly classify and grade 50 of flights
  during assessment with real-world data

• BAA Areas of Interest
• Developing the means to replicate the complex
  functionality of human intuitive reasoning to
  monitor the operations of an aircraft fleet in an
  automated fashion and identify indicators of
  potential mishaps using aircraft flight data
• Notional Path for Development
• Develop initial analysis model based on available
  operational data.
• Assess expert system results with control data
  sets implement requisite changes and updates
  validate.
• Assess validated model utilizing real-world
  aircraft data in a simulated squadron
  environment.

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Adaptive Expert System for Autonomous Detection
of Aviation Mishap Leading Indicators Current
Solutions / Techniques
Observation
Recognition
Grouping
Examination
Association
Mathematical Relationships
A/C Flight Data
Compare similarities to known groups
SOM
Genetic Algorithms
Clusters
Data Mining
Rule Extraction
Trees
Unsuccessful Prediction
Optimization Adaptation
Corroboration
Sufficient Information
Successful Prediction
Functions performed by current state-of-the-art
techniques.
Neural Networks
Statistics
Knowledge Process 1
Genetic Algorithms
Regression
Knowledge Process 2
Knowledge Process 3

• The proposed Adaptive Expert System approximates
  the
• human reasoning process and extends the
  state-of-the-art by incorporating mechanisms for
  corroboration and adaptation within the expert
  system architecture.

Expert system transforms knowledge processes
into actionable output.
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POINTS OF CONTACT

• Enabling Capability Manager
• Ms. Malinda G. Pagett, Code 352
• 703-588-11047
• malinda.pagett_at_navy.mil
• Advanced Helicopter Main Rotor Blade Erosion
  Coating Program Manager
• Dr. David Shifler, Code 332
• 703-696-0285
• david.shifler_at_navy.mil
• Adaptive Expert System Program Manager
• Dr. David Haas, Code 352/NSWC Carderock
• 301-227-1397
• david.haas_at_navy.mil