DOT/FAA/AR-98/26 A Review of the Flammability Hazard of ...

1 DOT/FAA/AR-98/26 Office of Aviation ResearchWashington, 20591A Review of the FlammabilityHazard of Jet A Fuel Vapor in CivilTransport Aircraft Fuel TanksJune 1998 Final ReportThis document is available to the publicthrough the National Technical InformationService (NTIS), Springfield, Virginia Department of TransportationFederal Aviation AdministrationNOTICEThis document is disseminated under the sponsorship of the of Transportation in the interest of information exchange. TheUnited States Government assumes no liability for the contents or usethereof.

2 The United States Government does not endorse products ormanufacturers. Trade or manufacturer s names appear herein solelybecause they are considered essential to the objective of this Report Documentation Page1. Report Government Accession Recipient's Catalog Title and SubtitleA Review OF THE Flammability Hazard OF JET A FUEL VAPOR IN5. Report DateJune 1998 CIVIL TRANSPORT AIRCRAFT FUEL TANKS6. Performing Organization CodeAAR-4227. Author(s)Fuel Flammability Task Group8. Performing Organization Report Performing Organization Name and AddressFire Safety Section, AAR-422 Federal Aviation Administration10.

3 Work Unit No. (TRAIS)William J. Hughes Technical CenterAtlantic City International Airport, NJ 0840511. Contract or Grant Sponsoring Agency Name and Department of TransportationFederal Aviation Administration13. Type of Report and Period CoveredFinal ReportOffice of Aviation ResearchWashington, DC 2059114. Sponsoring Agency CodeAAR-42215. Supplementary NotesCompiled by Richard Hill, Federal Aviation Administration, William J. Hughes Technical Center, Atlantic City InternationalAirport, AbstractThis report documents the findings of a Fuel Flammability Task Group made up of recognized fuel and combustion specialistsinvestigating the Flammability and explosiveness of fuel within an aircraft fuel tank.

4 The task group reviewed all availablereports on the subject and met and discussed the data with technical experts from Boeing Commercial Airplane Co., CaliforniaInstitute of Technology, and the National Transportation Safety Board. The scope of the report includes jet fuel definitions andspecifications, jet fuel Flammability data, influences of various factors on fuel Flammability , and predictive analyses and modelsfor Flammability . The report discusses the impact of this knowledge on the needs for in-flight fuel fire Key WordsIgnition, Explosion, Jet fuel, Flammability ,Fuel vapor18.

5 Distribution StatementThis document is available to the public through the NationalTechnical Information Service (NTIS), Springfield, Security Classif. (of this report)Unclassified20. Security Classif. (of this page)Unclassified21. No. of Pages6222. PriceN/AForm DOT (8-72)Reproduction of completed page authorizediiiTABLE OF CONTENTSPageEXECUTIVE SUMMARY vii1 INTRODUCTION Background Fuel Flammability Task Group

6 Past Fuel System Design for Fire Safety 22 DISCUSSION Jet Fuel Jet Fuel Specifications Properties Flash Point Specifications and Measurements Jet Fuel Flash Points Points and Flammability Hot-Surface Ignition Jet A Fuel Flammability Data

7 Ignition Data Need for Additional Data on Spark Ignition Hot-Surface Ignition Data Probability Formulation Determination of the Fuel/Air Mixture General Considerations Fuel Loading Effects Fuel Tank Geometry (Compartments)

8 Vertical Mixing Fuel Degassing Misting Mass Exchange With External Environment Determination of Fuel/Air Mixture Summary Thermal Modeling Need for Numerical Simulations Codes Being Developed Thermal Modeling Summary Fuel Tank Vulnerability Analysis Methodology

9 Methodology Development Example Application Code 403.

10 CONCLUSIONS 404. REFERENCES 425. UNCITED REFERENCES REVIEWED 45 APPENDIX A TASK GROUP RESUMESvLIST OF ILLUSTRATIONSF igurePage1 Flammability Limits for AVTAG/JP-4 and AVTUR/JP-832 Nonequilibrium Flammability Limits for AVTUR/JP-843 Flammability Limits for AVTUR Fuel Vapors and Mist44 Pressure Altitude Temperature Limits of Flammability for Jet A andJet B Type Fuels in Air55 Estimated Minimum Electrical Ignition Energies for Jet A/Jet A-1 andJet B Fuels56 Rate of Spread of Flame