What Are The Risks Involved In Refueling And Defueling Aircraft

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What Are The Risks Involved In Refueling And
Defueling Aircraft
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Aircraft refueling and de-fueling often lead by
attendant hazards which should be managed
sufficiently for their mitigation to acceptable
levels. The issues are same with tanker or fuel
hydrant system. Pressure refueling is normal for
business jets and multi-crew transport aircraft
but nowadays gravity refueling are available as a
backup system. The primary risk involves
unintended ignition of fuel vapor which can occur
by a single spark. Fuel vapor has a sufficient
quality that creates a high risk of ignition may
result from spillage arising from procedural
errors, leaks, aircraft tank venting or failure
of pressurized fuel lines or their couplings.
During refueling or de-fueling fuel, the movement
may lead to a static charge in building up in the
fuel. If the charge is in high potential, it can
cause sparking within the aircraft. The
possibility of sparks inside the tank and the
charge density in the fuel are not affected by
bonding. Accumulation of a surface static charge
may occur in either on aircraft bladder tank or
in its fueling vehicle under any certain
conditions. Electrical bonding must be used to
eradicate this hazard. Re-fueling should not take
place during thunderstorms.
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Electrical Bonding
There must be a cable to link between the point
or to clean unpainted metal surfaces on the
chosen airframe. Bonding cables should be
connected to the installation delivering the fuel
with the aircraft or installation receiving the
fuel. All connections should be made before
filler caps are removed earlier to start fueling
and then not broken until the fueling is
completed and filer caps are replaced where it is
appropriate. Keep in mind that Fuel Hoses
including conductive hoses are not suitable
substitutes for dedicated clips and bonding wires.
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Static Dissipater Additive
If turbine fuels do not contain a static
dissipater, then its quite impossible to load
wide-cut fuel. Wide-cut fuel is considered to be
involved when it's being supplied or when its
already presented in the aircraft tanks. It is
recommended that when wide-cut fuel has been used
then the next two uplifts of fuel should be
treated as wide-cut. A mixture of kerosene
turbine and wide-cut fuels can result in the
air-fuel mixture in the tank. The mixture is in
the combustible range at common ambient
temperatures during fueling.
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PED Use during Refueling
PED or personal electronic device may create or
induce a spark of sufficient intensity to ignite
fuel vapor released during fueling but it is
inaccessible under normal circumstances. The main
concern is the proliferation of below
specification mobile telephone batteries that
have the potential to fail dangerously. It is
unknown that whether such failure would be
sufficient magnitude to ignite a fuel or the air
mixture but the possibility still exists. It is
recommended under any circumstances during
refueling should be carefully considered and
mitigated. It also appears that personal
electronic devices close to or onboard modem
aircraft can interfere with fuel gauges. Some
navigation equipment may cause false fire
warnings in cargo or baggage holds. Airport
operators should prohibit the use of the personal
electronic device on the apron area in the
vicinity of refueling operations.
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Refueling of Aircraft Bladder Tank
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Refueling on the Passenger on Broad
Aircraft operators should have their procedures
for refueling including emergency evacuation and
if refueling is permitted with the passenger on
board then it should be appropriate with
operations manual and Cabin Crew Manual. Crew
stations and duties should be clearly defined
with passenger communication. The procedure of
emergency evacuation for passenger should be
taken into account the availability of air bridge
access or in-position ground steps in the
selection of exits to be used. One of the flight
crew should remain in the flight deck at least.
There is a common situation that is often
overlooked is where refueling commences after
gate arrival but before all passengers have got
off or started to get off. The crew busy with
their routine post-shutdown procedures may not be
aware that the doors have been opened and
disembarkation started. An unexpected requirement
to carry out an emergency evacuation might create
difficulties.
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Fire Hazard during Fueling and De-fueling
Due to the combustible nature of turbine engine
fuel and AVGAS, the potential for fire while
fueling and de-fueling aircraft must be
addressed. Always fuel and de-fuel outside, not
in a storage room that serves as an enclosed area
for vapors to build up to a combustible level.
Clothing worn during refueling personnel should
be safe not promote any static electricity
buildup, synthetics such as nylon should be
avoided. Cotton can be a safe way of handling
fuel.
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De-fueling
This is an infrequent and special operation. The
person involved including any flight crew should
be careful to refer any necessary procedural
documentation. Fuel removed from aircraft tanks
never reused and must be offloaded into a
dedicated de-fueling tanker.    Accident
There are many accidents or incidents occurs
during fuel loading, for example, Cathay Pacific
Airbus en route from Surabaya to Hong Kong
experienced difficulty in controlling engine
thrust. As the problem worsened one engine became
unusable and a PAN and then a MAYDAY was declared
to a successful landing at the destination with
excessive speed after control of thrust from the
remaining become impossible. Emergency evacuation
followed after the report of landing gear fire.
Saltwater contamination of the hydrant fuel
system at Surabaya after alterations during
airport construction work was found a polymer
contaminant in uplifted fuel.
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Contact Us
Liquid Containment Pty LtdPO Box 1334,
Mudgeeraba Queensland 4213
0405 138 664
info_at_liquidcontainment.com.au
http//www.liquidcontainment.com.au/