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Cabin & Fire Safety Reports
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| Title: |
Evaluation of Oxygen Cylinder Overpacks Exposed to
Elevated Tempature |
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Summary: |
Tests were conducted inside a large
industrial convection furnace to determine the temperature
and time required to cause pressure relief activation of
three different size oxygen cylinders commonly used in
commercial transport aircraft. The cylinders were first
emptied of gaseous oxygen for safety reasons and refilled
with nitrogen to the original pressure. The furnace
temperature was ramped to 400°F, which represented the
temperature reached during a Halon 1301 suppressed
deep-seated cargo compartment fire. Cylinder pressure
relief activation typically occurred after the surface
temperature had reached only 300°F.Additional tests
were conducted using a 76.5-cubic-foot oxygen cylinder
placed inside several types of cylinder cases, commonly
referred to as overpacks. The overpacks were available in
a variety of constructions, all for the purpose of
protecting the cylinder from impact damage that may occur
during shipment. The tests were run to determine the level
of thermal protection, if any, that the overpacks might
provide when the cylinders are subjected to elevated
temperatures. Two custom-made overpacks were also tested
that contained insulating materials aimed specifically at
providing thermal protection. Tests showed that some
common overpacks have the ability to protect the cylinder
from pressure relief activation for nearly 60 minutes
while other types designed specifically for thermal
insulation can provide significant additional
protection. |
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| Title: |
Full-Scale Test Evaluation of Aircraft Fuel Fire
Burnthrough Resistance Improvements |
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Summary: |
This report summarizes the research
and full-scale tests undertaken by the Federal Aviation
Administration (FAA) to evaluate the fuselage burnthrough
resistance of transport category aircraft that are exposed
to large postcrash fuel fires. Twenty-eight full-scale
tests were conducted in a reusable fuselage test rig to
determine the effectiveness of thermal-acoustical
insulation improvements in preventing or delaying fuselage
burnthrough. The testing showed that the method of
attaching the insulation to the fuselage structure had a
critical effect on the effectiveness of the insulation
material. In addition, the composition of the insulation
bagging material, normally a thermoplastic film, was also
shown to be an important factor. A number of fiberglass
insulation modifications and new insulation materials were
shown to be effective in varying degrees. For example, a
heat-treated, oxidized polyacrylonitrile fiber (OPF)
encased in a polyimide bagging material prevented
burnthrough for over 8 minutes. When contrasted with
current insulation materials, which were shown to fail in
as little as 2 minutes, effective fire barriers such as
the OPF insulation offer the potential of saving lives
during a postcrash fire accident in which the fuselage
remains intact. |
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| Title: |
A
Review of the Flammability Hazard of Jet Fuel Vapor in
Civil Transport Aircraft Tanks |
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Summary: |
This report documents the findings
of a Fuel Flammability Task Group made up of recognized
fuel and combustion specialists investigating the
flammability and explosiveness of fuel within an aircraft
fuel tank. The task group reviewed all available reports
on the subject and met and discussed the data with
technical experts from Boeing Commercial Airplane Co.,
California Institute of Technology, and the National
Transportation Safety Board. The scope of the report
includes jet fuel definitions and specifications, jet fuel
flammability data, influences of various factors on fuel
flammability, and predictive analyses and models for
flammability. The report discusses the impact of this
knowledge on the needs for in-flight fuel fire
prevention. |
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| Title: |
Initial Development of an Exploding Aerosol Can
Simulator |
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Summary: |
A device was constructed to simulate
an exploding aerosol can. The device consisted of a
cylindrical pressure vessel for storage of flammable
propellants and base product and a high-rate discharge
(HRD) valve for quick release of the constituents.
Simulator tests were conducted using representative
constituents and propellant quantities for comparison with
actual cans heated to the point of rupture and ignition.
This report describes the tests conducted with the
simulator in unconfined spaces, a B-727 cargo compartment,
and an LD-3 Unit Loading Device (ULD). Subsequent work is
planned with the aim of matching the ressure pulse
produced by the exploding aerosol can simulator with that
measured during an overheated aerosol can explosion. |
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