Improving aircraft safety throughfuel tank inerting technologyHoneywell Aerospace

Honeywell

1944 East Sky Harbor Circle

Phoenix, Arizona 85034

North America: 1.800.601.3099

International: 1.602.365.3099

www.honeywell.com

C61-0689-000-001May 2008© 2008 Honeywell International Inc.

On-Board Inert Gas Generation System (OBIGGS)Honeywell Aerospace

Honeywell is a leading global provider of

integrated avionics, engines, wheels and

brakes systems and service solutions for

aircraft manufacturers, airlines, business

and general aviation, military, space and

airport operations.

For more information on Honeywell

Aerospace, visit us online at

www.honeywell.com/aero

Global Network of Support Services

Honeywell’s resources span the Americas,

Europe, Middle East, Africa, Asia and the

South Pacific to deliver dedicated 24/7

service support. As a world leader in

aviation aftermarket services, our global

repair centers, logistics network and field

services engineering teams are able to

quickly repair, supply, and warranty equipment

whenever and wherever it is needed.

Find out more

To get more information on our OBIGGS

solution, send us an email at

obiggs@honeywell.com

HWELL3272-OBIGGsLet_FA.qxp:C61-0689-000-000 5/20/08 10:34 AM Page 1

The risk of fuel tank explosions has been a

common concern of aircraft manufacturers and

airlines since the beginning of commercial flight.

Using advanced fuel tank inerting technologies,

Honeywell has delivered the first FAA-certified

solution that enhances the safety of commercial

air transport. Our On-Board Inert Gas Generation

System (OBIGGS) substantially reduces the

possibility of ignition of flammable fuel vapors

in an aircraft’s fuel tank by lowering the oxygen

concentration below the level that will support

combustion. The result is safer aircraft operations.

There are three major causes of fuel tank

explosions as noted by the FAA*. All of which

are reduced by OBIGGS.

The first source is electrical arcing that may occur

if a part of the insulation on the electrical wire

bundles that run through the fuel tanks wears off,

exposing a small patch of bare wire, often not

visually discernable, that contacts a metal surface.

Second are friction sparks that can occur from

rotating components, such as a steel fuel pump

impeller, rubbing on the pump inlet check valve.

The final source is auto ignition, where combustion

can occur when the fuel/air mixture spontaneously

ignites from heat; even in the absence of an

ignition source.

Proven solution to cost-effectively enhance commercial aircraft safety

The first FAA-certified commercialair transport system that reduces theprobability of fuel tank explosions.

System Operation

The OBIGGS process starts with processed air,

which is conditioned to optimum pressure and

temperature and then passed through a series

of Air Separation Modules (ASM). The ASMs

separate the oxygen from the process air through

a permeable gas separation membrane, producing

primarily nitrogen-enriched air (NEA). The NEA is

delivered to the fuel tank where it displaces the

flammable fuel/air mixture to reduce the risk of

an explosion or fire.

The system consists of either an independent

Thermal Control Unit (TCU) or one that is

integrated with the Environmental Control System

(ECS), along with the Air Separation Unit (ASU)

and instrumentation to control the operation

and distribution of air to the fuel tanks.

Key OBIGGS Components

The following is a typical list of components

that are used in the fuel tank inerting system:

� Pressure regulating and shut-off valve

� Heat exchanger to condition the temperature

� High efficiency ozone converter to ensure

long ASM life

� Turbo compressor to condition the pressure

(not required for all applications)

� Valves used to control NEA distribution and

flow modes

� Pressure, temperature and oxygen sensors

� Contaminant filter

� Air separation modules

� Honeywell digital controller with full

built-in-test display

Leading Technologies

As a leading systems integrator, Honeywell is

responsible for the overall design, performance

and integration of our fuel tank inerting systems

and has formed industry partnerships to ensure

the best technologies are incorporated into

our OBIGGS solutions. Our fuel tank inerting

technologies have been installed on select

aircraft since 2005 for an in-service evaluation

and have accumulated over 20,000 flight hours

of proven operation.

Key OBIGGSAdvantages

� Integrated withexisting ECS toensure minimalaircraft impact

� Low air flowconsumptionensures minimalfuel-burn impact

� Extensive databaseof component designdata to ensure highcomponent reliability

� State-of-the-artoxygen sensingequipment

� Full developmentand test facilitiesto ensure systemoperability andtechnology readiness

� Over 50 years ofsystems engineeringand integration ofcomplex mechanicaland pneumaticaircraft systems

� Global supportnetwork to meetall productsupport needs

Preconditioned air from thethermal control unit

Oxygen Enriched Air (OEA)is vented overboard

Permeable membrane separatesoxygen from the process air

Nitrogen Enriched Air (NEA)delivered to the fuel tanks

OEA

NEA

Temperature control valve

Check valve

Fan

Heat exchanger

Ozone converter

Thermal Control Unit Air Separation Unit

*FAA Initial Regulatory Evaluation – Fuel Tank Flammability Reduction Report

HWELL3272-OBIGGsLet_FA.qxp:C61-0689-000-000 5/20/08 10:34 AM Page 3