Fuel Tank Safety

1
Fuel Tank Safety

• Mike Kaszycki, FAA
• Dave Gibbons, JAA

2
Fuel Tank Safety

• Harmonization of Unsafe Condition Criteria
• Fuel Tank Safety Reviews
• Implementation of Unsafe Condition Criteria
• Continued Operational Safety/Maintenance
• Fuel Tank Inerting
• Summary

3
Harmonization of Unsafe Condition Criteria

• FAA and JAA fuel tank safety review requirements
  reference different regulations
• FAA FAR 25.901 25.981(a) (b), amendment
  25-102
• JAA JAR 25.1309
• FAA and JAA developed harmonized policy
• Includes unsafe condition criteria for
  determining mandatory action from SFAR 88 JAA
  fuel tank safety reviews.
• JAA issued policy letter on February 3, 2003
• FAA issued policy memorandum on February 25, 2003
  
• Expectation is to have common solution set.

4
Unsafe Condition Criteria

• Four-Element Unsafe Condition Evaluation Criteria
• Element 1. Single Failures all tanks
• Element 2. Combination of failures
• a) Fuel tanks with low flammability exposure
  time Known combinations of failures are
  considered an unsafe condition.
• b) Fuel tanks with high flammability exposure
  time Non-compliant design features and
  associated maintenance actions identified by the
  system safety analysis will be used for
  establishing unsafe condition.
• Element 3. Unacceptable service experience all
  tanks
• Element 4.  Determination of the flammability
  exposure time of each fuel tank
• Heated CWT High flammability exposure
• Other tanks Low flammability exposure

5
Fuel Tank Safety Reviews

• FAA/JAA are participating in joint SFAR 88
  reviews of several type certificate holders,
  together with certifying authorities
• Airbus (Toulouse) March 19 - 20
• Boeing (Seattle) April 22 - 25
• Embraer (Ft. Lauderdale, FL) April 29 May 1
• Bombardier (Montreal) May 6 8
• Other TC holder reviews may only have the
  certifying authority participation, depending on
  the results of the above reviews (JAA will
  provided standardization of European NAA reviews).

6
Implementation of Unsafe Condition Criteria

• OEM review identified harmonization issues with
  implementation of the unsafe condition criteria.
• Authorities differed in interpretation of
  portions of the unsafe condition criteria.
• We are committed to jointly resolving open issues
  from SFAR 88 review.

7
Continued Operational Safety/Maintenance

• SFAR 88 requires identification of additional or
  enhanced maintenance and inspection procedures,
  in addition to possible design changes.
• When SFAR 88 was issued, FAA believed the most
  practical method to incorporate necessary
  maintenance and inspection instructions would be
  by operating rules.
• After rule was issued, several aviation
  authorities and industry groups indicated
  mandating by airworthiness directives would be
  preferred.
• As part of the harmonization program, the FAA
  agreed that airworthiness directives would be
  used to mandate any maintenance and inspection
  procedures required to address unsafe conditions.

8
Continued Operational Safety/Maintenance

• FAA will change the operating rules back to their
  pre-SFAR 88 wording.
• FAR sections 91.410(b), 121.370(b), 125.248(b)
  and 129.32(b).
• ADs will be issued to require maintenance actions
  necessary to address unsafe conditions.
• Maintenance and inspection instructions not
  required to address unsafe conditions will be
  evaluated under existing standard maintenance
  review processes.(e.g., MRB)
• If practical, ADs will use the December 6, 2004,
  compliance date to be harmonized with JAA policy
  letter.
• Any change to this target date will be harmonized
• Requirement deleted for U.S. operators to perform
  a design reviews for STC holders who did not
  complete SFAR 88 reviews.

9
Fuel Tank Inerting

• Boeing applied to FAA for certification of
  Flammability Reduction System (FRS) for 737 and
  747 airplane models.
• FRS is based on using fuel tank inerting system
  to reduce center wing tank flammability
• Boeing applied to JAA for 737 Next Generation
  models to formalize harmonization process.
• FAA and JAA have developed harmonized
  certification requirements.
• FAA 737 issue paper P-1 contains proposed FAA
  special conditions
• JAA CRI PTC E-10 contains proposed JAA special
  conditions
• Plan is to publish both FAA and JAA proposed
  special conditions for comment concurrently in
  June 2003 with 60 day comment period.

10
Fuel Tank Safety Summary

• Harmonization of implementation of the unsafe
  criteria continues to support common solution
  set.
• Fuel tank safety reviews are taking place to
  support mandatory action decisions by June 2003.
• FAA and JAA have harmonized certification
  requirements for fuel tank inerting.