Systems Fire Protection Working Group DTA - Grenoble, France June 21-22, 2003 FAA Inerting System Flight Testing on an Airbus A320 William Cavage AAR-440 Fire Safety Research Federal Aviation Administration

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Outline Goals and Objectives OBIGGs Instrumentation –System –Center Wing Tank –OBOAS –Additional Parameters Analysis Data –System Performance –Fuel Tank Inerting Summary

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Testing Goals and Objectives Validate the simplified inerting concept and develop/expand upon existing system performance models Examine system sizing requirements Validate in flight inert gas distribution assumptions Examine potential operational effects on the ability of a system to maintain inert conditions in a fuel tank

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D OBIGGS - System Architecture Uses Air Separation Modules based on HFM technology –Excepts hot air from aircraft bleed system –Cools, filters, and conditions air –Air is separated by ASMs and NEA is plumbed to output valves to control flow –OEA is dumped overboard, H/X cooling air deposited in cargo bay near outflow valve –System configured to operate in high and low flow modes Prototype system controlled by control box in cabin that is connected to system with cable Install system in test aircraft cargo bay for simplicity sake

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D FAA OBIGGs Installation Drawing

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D FAA OBIGGs Installation Drawing

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D FAA OBIGGS Installation

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Instrumentation and Data Acquisition Various thermocouples and pressure transducers used to evaluate system performance OBIGGS system flow meter and 2-channel oxygen analyzer for NEA and OEA analysis Eight sample locations within the Center-Wing Tank (CWT) –FAA Onboard Oxygen Analysis System (OBOAS) utilized Aircraft parameters measured Airbus data acquisition system utilized –Full-up flight worthy DAS

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D System Instrumentation Diagram Static Pressure Temperature Spare [O 2 ] Static Pressure Temperature OEA [O 2 ] Temperature Static Pressure Temperature Temperature (FAA Reader) Static Pressure Temperature NEA [O 2 ] Penetration Hole

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Flow Meter

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D CWT Instrumentation NEA Deposit Vent Location

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D OBOAS Mounted in A320 Test Aircraft

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Test Plan Operated system in two flow mode for a series of tests with a 39,000 ft cruise altitude and a high rate of descent (4k ft/min) –Descended to 3,000 feet for operational purposes –Nine total tests, 6 relative to FAA testing goals and objectives –Used OBIGGS in both a single ASM configuration and a 2-membrane configuration to evaluate sizing requirements Testing proved the FAA system concept, acquired system sizing data, and examined the effects of several operational conditions –Studied effect of fuel on an inert ullage –Studied effect of the high flow mode on the inert ullage –Studied effect of bleed air on the membrane performance

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Table of Airbus Flight Tests

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Data Analysis Calculation of bleed air consumed Model of Ullage gas Oxygen Concentration = Mass of oxygen in tank at time t = Mass flow rate of inerting gas (in terms of t) IGOF = Fraction of oxygen in inerting gas Δρ= Change in Ullage Density due to Altitude Change V Tank = Volume of Tank Ullage m Tank = Mass of Gas in Tank m air = Mass of air entering tank With: = NEA Oxygen Concentration = OEA Oxygen Concentration

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Results - System Performance System performed as expected with predictable ASM dynamic charactaristics – Easily predicted with static measurements 2-membrane system configuration gave approximately double the NEA –Less at altitude probably due to OEA back pressure Bleed air consumption greater then expected –Aircraft bleed air pressures were higher then expected at altitude ASM degraded during the ground and flight testing (~ 100 hours) giving about a 14% reduction in productivity –Not much more then normal expected “break-in” of ASM

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D System Performance Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D One vs. Two ASM Performance Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Bleedair Consumption Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Results - Tank Inerting CWT inerting accomplished easily –No stratification observed, ullage acted in a very homogenous manner Two ASM inerting gave very little benefit compared to a single ASM –Different system “tuning” could change that High flow mode effective at helping maintain a low resulting ullage oxygen concentration during descent Fuel load had very little effect on measured ullage oxygen concentrations for both static and consumed fuel loads Simple model effective at predicting resulting ullage oxygen concentration given a system performance and mission profile

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D CWT Inerting Oxygen Concentration Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D One vs. Two ASM Tank Inerting Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D High Flow Mode Benefit Tank Inerting Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D Effects of Fuel Tank Inerting Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D System Performance Data

Airbus Inerting Flight Test ___________________________________ AAR-440 Fire Safety R&D FAA simplified OBIGGS concept validated –System performance predictable –Bleed air consumption significant –ASM performance degradation needs to be studied further Fuel tank inerting –Inert gas distribution accomplished easily –System tuning needs to be studied further to say true benefit of 2 ASMs versus 1 –Two flow mode beneficial –Fuel load effected resulting ullage oxygen concentration very little –Ullage inerting easily modeled given a system performance Summary