20068641 aircraft fuel systems
Post on 07-Apr-2018
240 Views
Preview:
TRANSCRIPT
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 1/36
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 2/36
Aircraft Fuel
Reciprocating engine fuels
Turbine engine fuels
Jet A – which is Kerosene Jet B – a blend of kerosene and
gasoline
Jet A-1 – used for operation at
extremely low temperatures• Jet A and Jet B are the most common
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 3/36
Fuel System Contamination
The higher the viscosity of the fuel, the greaterit’s ability to hold contaminants in suspension
This is why jet fuels, which have a higherviscosity than av-gas, are also more susceptibleto contamination than av-gas
The main contaminants that reduce the qualityof fuel are: Other petroleum products
Water
Rust
Scale
Dirt
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 4/36
Water Contamination
Water contamination in fuel can be in twoforms: Dissolved in the fuel
Entrained or suspended in the fuel Water in fuel can cause icing in the
aircraft fuel system, usually in: Boost pump screens
Low pressure filters Large amounts of water can cause engine
stoppage
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
E S l Ali S d
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 5/36
Microbial Growth
Microbial Growth is produced by variousforms of micro-organisms that live andmultiply in water which is in jet fuel
These micro-organisms form slime thatcan be red, brown, green, or black
The organisms feed on hydrocarbons inthe fuel but require water to multiply
This buildup can: Interfere with fuel flow and quantity
indications
Start electrolytic corrosive action
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
E S l Ali S d
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 6/36
Contamination Detection
Coarse fuel contamination can bedetected visually
Uncontaminated fuel should be: Clean
Bright
Contain no perceptible free water
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
E S l Ali S d
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 7/36
Contamination Detection(cont.)
Clean means the absence of any readilyvisible sediment or entrained water
Bright refers to the shiny appearance of
clean, dry fuel
Free water is indicated by a cloud, haze,or water slug
Water saturated in fuel is not always visible Perfectly clear water can contain as much as
three times the acceptable limit
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr Salman Ali S ed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 8/36
Contamination Detection(cont.)
There is no accurate method of detectingfuel entrained water when it is frozen
For this reason, it is important that fuel is
checked when the water is in a liquidstate This should not be done following a flight at
altitude when the fuel would be below 32degrees F
It is more effective to drain the fuel after thefuel has set undisturbed for a period of time,allowing the water to precipitate and settle tothe drain point
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 9/36
Fuel Systems
The purpose of an aircraft fuel system isto store and deliver the proper amount of clean fuel at the correct pressure to the
engine Fuel systems should provide positive and
reliable fuel flow through all phases of flight including:
Changes in altitude Violent maneuvers
Sudden acceleration and deceleration
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 10/36
Fuel Systems (cont.)
Fuel systems should alsocontinuously monitor systemoperation such as:
Fuel pressure
Fuel flow
Warning signals
Tank quantity
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 11/36
Types of Fuel Systems
Fuel systems can be classified in twobroad categories:
Gravity-Feed Systems Pressure-Feed Systems
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 12/36
Gravity-Feed Systems
Gravity-Feed Systems use only theforce of gravity to push fuel to theengine fuel-control mechanism
The bottom of the fuel tank must behigh enough to provide adequatepressure to the fuel-controlcomponent This type of system is often used in
high-wing light aircraft
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 13/36
Pressure-Feed Systems
Pressure-Feed Systems require the use of a fuelpump to provide fuel-pressure to the engine’sfuel-control component
There are two main reasons these systems are
necessary: The fuel tanks are too low to provide enough pressure
from gravity
The fuel tanks are a great distance from the engine
Also, most large aircraft with higher powered
engines require a pressure system regardless of the fuel tank location because of the largevolume of fuel used by the engines
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 14/36
Fuel System Components
Pumps
Tanks
Lines
Valves
Fuel Flow-meters
Filters and
Strainers
Quantity Indicators
WarningComponents
Fuel Drains
Heaters
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 15/36
Fuel Pumps
Fuel pumps are used to move fuelthrough the system then gravity feed isinsufficient
There are three main functions of fuelpumps, they are to move fuel from:
The tanks to the engines
One tank to another
The engine back to the tanks
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 16/36
Fuel-Pump Requirements
Engine fuel systems require mainpumps and in some systemsemergency pumps
These requirements depend on thetype of engines installed on theaircraft
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 17/36
Reciprocating-Engine Fuel-Pump Requirements
Reciprocating-engines which are notgravity-fed require:
At least one main pump for each engine These pumps must be engine-driven
The pump capacity must capable of providing enough fuel flow for all
operations
Engr. Salman Ali SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 18/36
Turbine-Engine Fuel-PumpRequirements
Turbine-Engines require:
At least one main pump for each engine
Main pump power supply must beindependent of all other main pumppower supplies
Each positive-displacement main pump
must be able to be bypassed
g . Sa a SyedSaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 19/36
Turbine-Engine Fuel-PumpRequirements (cont.)
Turbine-engines also require emergencypumps The emergency pump must be immediately
available to supply fuel to the engine in theevent of a main pump failure
Emergency pump power supplies must beindependent of that of the corresponding mainpump
If both the emergency and main pumpsoperate continuously, there must be somemeans of alerting the flight crew of a failure of either pump
g ySaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali Syed
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 20/36
Fuel Pump Classification
One way to classify fuel pumps isaccording to the pump’s function
These classifications are: Boost Pump
Scavenge Pump
Cross-feed Pumps
g ySaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali SyedS di El i i C
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 21/36
Fuel Pump Classification
Another way to classify fuel pumpsis by their method of operation
These pumps are: Vane-type
• Variable-volume
Centrifugal
Ejector
g ySaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali SyedS di El t i it C
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 22/36
Vane-Type Pumps
Vane-type fuel pumps are the mostcommon
They use a rotor which turns vanesin a cylinder, the vanes act to pushthe fuel through the system
Vane-type pumps can have fromtwo to six vanes and they may bevariable volume also
g ySaudi Electricity Company
Abha-Saudi Arabia
Engr. Salman Ali SyedS di El t i it C
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 23/36
Centrifugal Pumps
Centrifugal pumps are used to movefuel from one tank to another orfrom the fuel tank to the engine
They are electrically driven andsome may operate at differentspeeds
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSa di Electricit Compan
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 24/36
Ejector Pumps
An ejector pump is normally used toscavenge fuel from remote areas
These pumps have no moving partsthey rely on return fuel from theengine to pump the fuel
Ejector pumps work on the venturiprinciple
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 25/36
Fuel Tanks
Fuel systems on different aircraftmay use several types of fuel tanks
The three basic types of fuel tanksused on aircraft are:
Integral
Rigid Removable
Bladder
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 26/36
Integral Fuel Tanks
Integral Fuel Tanks are commonly located in theaircraft’s wings or fuselage
These tanks are ones that are built into thestructure of the aircraft and generally can not be
removed Integral Fuel Tanks are formed by the actual
structure of the aircraft
The seams are sealed, usually with syntheticrubber, to produce an area inside the aircraftstructure which will contain the fuel
This type of tank is used in some light high-performance aircraft and turbine-poweredtransports
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 27/36
Rigid Removable Fuel Tanks
Rigid removable fuel tanks are oftenmade of aluminum components that arewelded together
These tanks are installed incompartments specifically made for thetank
The tanks may be held in place with
padded straps This type of tank is often found on more
expensive light aircraft and reciprocating-engine-powered transports
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 28/36
Bladder Type Fuel Tanks
Bladder type fuel tanks are basically areinforced rubberized bag
These tanks are installed in
compartments which support the weightof the fuel
The tank is held in place with buttons orsnaps on the bottom and sides of the
tank This type of tank is usually found on light
aircraft and some turboprop and turbine-powered aircraft
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 29/36
Fuel Lines
Fuel lines on aircraft are either made of rigid metal tubing or flexible hose
Most of the fuel lines are the rigid type
which are usually made of aluminumalloys
The flexible hose fuel lines are eithermade of synthetic rubber or Teflon
The diameter of tubing used is decided bythe engine’s fuel requirements
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 30/36
Valves
Fuel selector valves are used inaircraft fuel systems to:
Shut off fuel flow
Cross-feed
Transfer fuel
Selector valves may be operated
manually or electrically dependingon the installation
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 31/36
Filters and Strainers
Fuel is usually strained at three points inthe system
Through a finger or bootstrap strainer in
the bottom of the fuel tank Through a master strainer which is
usually located at the lowest point in thesystem
Through a third strainer near the fuelcontrol unit
Saudi Electricity CompanyAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 32/36
Quantity Indicators
Mechanical
Inverted float gauge
Rotating dial gauge
Upright float gauge
Sight-glass gauge
Resistance
Capacitance
y p yAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 33/36
Fuel Subsystems
Some aircraft fuel subsystems allowfor fuel:
Jettison Heating
Cross-Feeding
y p yAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 34/36
Fuel Jettison
The fuel jettison system comprises acombination of fuel lines, valves,and pumps provided to dump fueloverboard during an in-flightemergency
This will reduce the weight of the
aircraft so an emergency landing ispossible
y p yAbha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 35/36
Fuel Heating
Fuel heating is necessary for turbineengines to thaw ice particles in thefuel that would otherwise clog the
filters Fuel is routed through a heat
exchanger that uses either engineoil or compressor bleed air to bringthe fuel up to an acceptabletemperature
Abha-Saudi Arabia
Engr. Salman Ali SyedSaudi Electricity Company
8/6/2019 20068641 Aircraft Fuel Systems
http://slidepdf.com/reader/full/20068641-aircraft-fuel-systems 36/36
Cross Feeding
Cross feed systems allow the flow of fuel from any of the tanks to any of the engines
Some reasons that this systemmight be used are: Engine failure
Problem with one or more fuel tanks Redistribute fuel for weight and balance
purposes
Abha-Saudi Arabia
top related