Overview of Fuel Tank Flammability Reduction Rule

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Overview of Fuel Tank Flammability Reduction Rule
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Fuel Tank Flammability Reduction Rule
Part 25 Rules Amendment 25-125 Subpart E-
Powerplant  25.981 Fuel Tank Ignition
Prevention Appendix M Fuel Tank Flammability
Exposure Requirements Appendix N Fuel Tank
Flammability Exposure Analysis

• Part 26 Rules
•  26.33 Holders of Type Certificates
•  26.35 Changes to Type Certificates
•  26.37 Pending Type Certification Projects
•  26.39 Production Certificate Holders

Operations Rules 121.1117 (FRM) 125.509 (FRM)
129.117 (FRM)
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New Rule Requires

• Part 25 Certification Standards
• New Section 25.5 - Incorporation by Reference
• Incorporates Fuel Tank Flammability Assessment
  Method Users Manual for 25.981 and Appendix N
• Amends Section 25.981
• Replaces amd. 25-102 minimize fuel tank
  flammability standard with limits for all fuel
  tank types
• Main tanks and external Normally Emptied fuel
  tanks - 3 Fleet Average Flammability Exposure or
  (equivalent) conventional unheated aluminum wing
  tank
• Normally Emptied and any part located inside
  fuselage - Appendix M requirements
• 3 Fleet Average Flammability Exposure and 3
  warm day
• Adds fuel tank flammability airworthiness
  limitation requirement
• New Appendices to Part 25
• Appendix M Fuel Tank System Flammability
  Reduction Means
• Appendix N - Fuel Tank Flammability Exposure and
  Reliability Analysis

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New Rule Requires (continued)

• Part 26 Design Approval Holder (DAH) Rule
• Flammability analysis of all fuel tanks in large
  transports
• Flammability airworthiness limitations required
  for all TC Holders fuel tanks
• FRM service instructions from TC Holders for all
  high flammability tanks
• Any tank Above 7 percent reduced to below 7
  percent average except Normally Emptied and part
  inside fuselage
• Reduce to 3 percent average 3 percent warm day
  if above 7 percent, Normally Emptied tanks and
  any part located inside fuselage
• FRM on new production airplane with high
  flammability fuel tanks
• STC and field approved auxiliary tanks require
  design change if existing design compromises
  CDCCL for TC holder tank with FRM
• Pending Type Certification Projects - (e.g. A350,
  787). Flammability require compliance to amd.
  25-125

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New Rule Requires (continued)

• Operational Rules (Parts 121, 125 and 129)
• Passenger Use Airplanes
• Retrofit of 1992 and newer passenger airplanes in
  fleet
• 50 after 6 years,
• 100 after 9 years.
• Any pre 1992 airplane in passenger use must have
  FRM 9 years after effective date
• 1 year extension in compliance time provided if
  ground air use implemented when available at the
  gate
• Once installed, FRM must be operational and
  maintained per TC holders airworthiness
  limitations.
• Cargo Airplanes
• All newly delivered passenger and cargo airplanes
  to have FRM 2 years after effective date.
• Any passenger airplanes converted to cargo must
  maintain FRM

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Timeline for DAH and Operators
9/2008
9/2018
9/2010
9/2014
9/2015
9/2017
Expected 25 years in passenger service
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Guidance Materials

• AC 25.981-2A Fuel Tank Flammability Reduction
  Means
• AC 121-xxx