Fuel Tank Inerting Harmonization Working Group Team Reports

Ground-Based Inerting Designs Task Team Final Report
TABLE OF CONTENTS
1.0 ABSTRACT ....................................................................................................................................C-1
2.0 INTRODUCTION...........................................................................................................................C-1
3.0 BACKGROUND.............................................................................................................................C-2
4.0 APPLICABILITY ...........................................................................................................................C-2
5.0 SYSTEM DESIGN ASSUMPTIONS.............................................................................................C-3
6.0 DESIGN CONSIDERATIONS.......................................................................................................C-3
6.1 Specific Inert Gas Selection.................................................................................................C-3
6.2 Basic Inert Gas Introduction................................................................................................C-4
6.2.1 Ullage Washing.....................................................................................................C-5
6.2.2 Fuel Scrubbing......................................................................................................C-5
6.2.3 Fuel Flow Injection ...............................................................................................C-6
6.2.4 Combinations ........................................................................................................C-6
6.3 Ullage Gas Distribution.......................................................................................................C-6
6.3.1 Ullage Washing Through Existing Refueling Manifold .......................................C-6
6.3.2 Ullage Washing Through Existing Fuel Tank Vent System.................................C-7
6.3.3 Ullage Washing Through a Dedicated Distribution Manifold..............................C-7
6.3.4 Alternatives for Gas Distribution..........................................................................C-7
6.4 Servicing Considerations.....................................................................................................C-7
6.5 Other System Considerations ..............................................................................................C-8
6.6 MMEL/Maintenance Considerations...................................................................................C-8
6.7 System Costs........................................................................................................................C-9
6.8 Environmental Issues...........................................................................................................C-9
7.0 GROUND SUPPLY REQUIREMENTS ........................................................................................C-9
7.1 NEA Purity ..........................................................................................................................C-9
7.2 NEA Volumes Required....................................................................................................C-10
7.3 Ground Supply Pressure ....................................................................................................C-12
7.4 Ground Based Gas Supplies ..............................................................................................C-13
8.0 GENERAL AIRPLANE SYSTEM DESIGN ...............................................................................C-14
8.1 General System Layout .....................................................................................................C-14
8.2 Servicing Interface.............................................................................................................C-16
8.3 Servicing Panel Location...................................................................................................C-16
8.4 General System Design Analysis.......................................................................................C-17
8.5 Ground and Flight Testing Experience..............................................................................C-18
8.6 System Controls.................................................................................................................C-19
8.7 System Operation and Servicing .......................................................................................C-20
8.8 Auxiliary Tank Design Issues............................................................................................C-20
8.8.1 Auxiliary Tank Pressurization Alternative..........................................................C-21
9.0 EQUIPMENT REQUIRED...........................................................................................................C-21
9.1 NEA Servicing Interface....................................................................................................C-21
9.1.1 Witness Drains....................................................................................................C-22
9.1.2 Isolation Valve ....................................................................................................C-22
9.1.3 Non-Return Valve...............................................................................................C-22
9.1.4 Thermal Relief Valve..........................................................................................C-23
9.1.5 Indication and Control ........................................................................................C-23
9.1.6 Drain Valves .......................................................................................................C-23
9.1.7 Placards...............................................................................................................C-23
9.2 Auxiliary Tanks .................................................................................................................C-23
9.3 Additional Equipment Required........................................................................................C-23
C-iii