Fuel Tank Safety: Fuel Tank Safety Ali Bahrami – FAA Pascal Medal - EASA


Overview: Overview Background Harmonization Goals Ignition Source Prevention Status Flammability Reduction Status


Fuel Tank Safety - Background: Fuel Tank Safety - Background 2004 + Today THAI 737 ARAC 2 1996 SFAR 88 Reviews Flammability Reduction Ignition Prevention


SFAR 88 Lessons Learned: SFAR 88 Lessons Learned Goal of SFAR 88 was to preclude ignition sources Safety Assessments were very valuable Design reviews revealed unexpected ignition sources Difficulty in identifying all ignition sources Number of previously unknown failures found Continuing threat from still unknown failures Unrealistic to expect we can eliminate all ignition sources Must consider flammability reduction of high flammability tanks as an integral part of system safety


Balanced Approach withFlammability Reduction: Balanced Approach with Flammability Reduction Flammability Reduction significantly reduces hole size in flammability layer, virtually eliminating future accidents.


Fleet Average Flammability ExposureTypical Tanks with Jet A Fuel: Fleet Average Flammability Exposure Typical Tanks with Jet A Fuel Main Wing Tanks 2-4% Tail Tanks 2-4% Body Tanks Un-pressurized >20% Pressurized <5% Center Wing Tank with Adjacent Pack Bays 15-20% Center Wing Tanks without Pack Bays 4-7%


Harmonization Goal: Harmonization Goal To establish mutually acceptable positions between the FAA and EASA related to fuel tank safety, working within the requirements of the existing and developing rules and policies, while respecting the responsibilities of the State of Design: Resulting in a common solution set for the operators, and Facilitating transfer of airplanes from country-to-country with minimal impact on operators.


Harmonization Process: Harmonization Process FAA and EASA have closed SFAR 88 open issues FAA and EASA are coordinating common SFAR 88 closure letters that will be sent to manufacturers Weekly internal FAA team meetings to monitor all fuel tank safety activity EASA internal team coordination Biweekly FAA, EASA and TCCA telecons to continue and reinforce harmonization effort


Ignition Prevention Status: Ignition Prevention Status Ignition prevention safety reviews completed Design changes have been identified Common solution set agreed TC holders are preparing service bulletins and ADs are being issued


Ignition Prevention – Operating Requirements: Ignition Prevention – Operating Requirements Operating rules compliance dates extended FAA/EASA had required incorporation of maintenance program changes by December 2004 FAA notice extended compliance date to December 2008 EASA plans to extend operating rule compliance date December 2005 for Airworthiness Limitations (ALIs, CDCCLs) December 2006 for other maintenance information Harmonized SFAR 88 maintenance policy memo published; EASA equivalent being prepared ADs being issued for safety critical maintenance ALIs, CDCCLs Not all TC holders have developed maintenance instructions required by SFAR 88/JAA-EASA policy


Flammability Reduction Harmonization Status: Flammability Reduction Harmonization Status FAA and EASA agree on flammability reduction measures for new production airplanes and future designs FAA and EASA continue to work toward common retrofit position Plan agreed for working toward harmonization FAA plans to propose a flammability reduction rule later this year 2005 Special conditions are harmonized FAA issued final rule 747 special conditions January 24, 2005 EASA finalizing their final rule special conditions Harmonized special conditions will be issued for other certification projects


Summary: Summary Balanced approach of ignition prevention and reduced flammability can provide a substantial improvement in fuel tank safety Reducing flammability is now practical Ignition prevention still major protection strategy Combined strategies should virtually eliminate risk of future fuel tank explosions FAA and EASA have been working to harmonize fuel tank safety programs Ignition prevention actions are harmonized Significant progress made in harmonizing flammability reduction Reached agreement on flammability reduction standards for in- production aircraft and new designs Plan agreed for working toward agreement on retrofit