passenger aircraft subsystems

8/14/2019 Passenger Aircraft Subsystems

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SCHOOL OF AEROSPACE ENGINEERING

ESA 371AIRCRAFT SUB-SYSTEMS ELEMENTS

AY 2008/2009

PASSENGER AIRCRAFT SUBSYSTEMS

AIRBUS A320-200

BOEING 737-700

MCDONNELL DOUGLAS MD-88

Lecturer

Prof. Vladimir Zhuravlev

Prepared ByChan Ray Mun 92226


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Contents

Page

1.0 Introduction 2

1.1 Airbus A320-200 3

1.2 Boeing 737-700 5

1.3 McDonnell Douglas MD-88 8

2.0 Characteristics Table 11

3.0 Crew Size and Functions 12

4.0 Main Onboard Equipment Systems 14

4.1 Environmental Control Systems 14

4.2 Passenger and Cargo Cabin Systems

4.2.1 Interior Layout

4.2.2 Passenger Compartment Equipment

4.2.3 Water and Waste System

19

19

22

26

4.3 Crew Compartment Equipment 28

4.4 Hydraulic Systems 38

4.5 Pneumatic Systems 45

4.6 De-icing and Anti-icing Systems 48

4.7 Emergency Systems

4.7.1 Warning System

4.7.2 Fire Protection

4.7.3 Passenger Evacuation

4.7.4 Emergency Oxygen

52

53

55

57

57

4.8 Engine Control Systems 61

4.9 Flight Control Systems 66

4.10 Landing Gear Systems 72

5.0 Reference 78


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1.0 Introduction

A fixed-wing aircraft is a heavier-than-air craft whose lift is generated not by wing motion

relative to the aircraft, but by forward motion through the air. Fixed-wing aircraft range from

small training and recreational aircraft to large wide-body aircraft and military cargo aircraft.

Many fixed-wing aircrafts have been designed and manufactured to perform different missionspecifications. An airliner is a large fixed-wing aircraft with the primary function of transporting

paying passengers. Such aircraft are usually operated by an airline which owns or leases theaircraft. There are several types of airliners:

Wide-body

aircraft Twin-aisle aircraft used for long-haul flights between airline hubs and

major cities with many passengers

Boeing 747, Airbus A380, Lockheed L-1011 TriStar, McDonnellDouglas MD-11 and Ilyushin Il-96.

Narrow-body

aircraft Single aisle aircraft generally used for medium-distance flights with

fewer passengers than their wide-body counterparts

Boeing 737, McDonnell Douglas DC-9 & MD-80/MD-90 series,Airbus A320 family, Tupolev Tu-204, Tu-214, Fokker F70/F100

Regional airliner Fewer than 100 passengers and may be powered by turbofans orturboprops

Used for short flights between small hubs, or for bringing passengers tohub cities where they may board larger aircraft

Embraer ERJ, Bombardier CRJ series, ATR 42/72 and Saab 340/2000Commuter

aircraft Air taxis, with 19 or fewer passenger seats Lack such amenities as lavatories and galleys and typically do not carry

a flight attendant

Fairchild Metro, Jetstream 31/41, IPTN CN-235, Beechcraft 1900, andEmbraer EMB 110 Bandeirante

Narrow-body aircraft is an airliner with a cabin diameter typically of 3 to 4 metres and airline

seat arranged 2 to 6 abreast along a single aisle. Narrow-body aircraft seating less than 100 passengers are commonly known as regional airliners. For comparison, typical wide-body

aircraft can accommodate between 200 and 600 passengers, while the largest narrow-body

aircraft currently in widespread service the Boeing 757-300 carries a maximum of about 250.

The focus of this project is on narrow-body aircraft namely;

Airbus A320-200

Boeing 737-700

McDonnell Douglas MD-88


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1.1 Airbus A320-200

Fig 1.1 Swiss International Air Lines Airbus A320-200 (HB-IJQ) landing at London Heathrow Airport

Airbus A320 is from the Airbus A320 family of short to medium-range commercial passenger

airliners and is Airbus first entry into the narrow-body market. A320 was first delivered in 1988

and pioneered the use of digital fly-by wire control systems in a commercial airliner. The A320-

200 features wingtip fences and increased fuel capacity over the A320-100 for increased range.

The A320-200 can carry 150 passengers in a two-class configuration and 180 passengers ina single-class configuration. Typical range with 150 passengers for A320-200 is 2900

nautical miles or 5400 kilometres.

Advanced features introduced in A320 include:

The first fully digital fly-by-wire flight control system in a civil airliner. Fully glass cockpit Widespread use of composites The ECAM (Electronic Centralized Aircraft Monitoring) concept LCD (liquid crystal display) units in the flight deck instead of the original CRT (cathode ray

tube) displays

The design of A320-200 follows the airworthiness standards of BCAR Section C and

Section D in British Civil Airworthiness Requirements issued by the Civil Aviation

Authority of Great Britain.


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Overall View

Fig 1.2 3-view of Airbus A320-200

Airbus A320-200 Dimensions

Overall Length 37.57 m

Height 11.76 m

Fuselage Diameter 3.95 mMaximum Cabin Width 3.70 m

Cabin Length 27.51 m

Wing Span (geometric) 34.10 m

Wing Area (reference) 122.6 m2

Wing Sweep (25%

chord)

25 degrees

Wheelbase 12.64 m

Wheel Track 7.59 m


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1.2 Boeing 737-700

Fig 2.1 easyJet Boeing 737-700 lands at Bristol International Airport, Bristol, England

Boeing 737 is a short to medium range, single aisle, narrow-body jet airliner. It has nine variants,

from the early -100 to the most recent and largest, the -900. Boeing 737-700 is in the newervariant of Boeing 737 family called 737 Next Generation.

Boeing 737-700 typically seats 132 passengers in a two class cabin or 148 in all economy

configuration. The maximum range of 737-700 is 3365 nautical miles or 6230 kilometres.

New features of 737 Next Generation include:

Improved CFM56-7 turbofan engine, 7% more fuel efficient than the CFM56-3 Intercontinental range of over 5,556 km Increased fuel capacity and higher Maximum Takeoff Weight (MTOW) Six-screen LCD glass cockpit with modern avionics, retaining crew commonality with

previous generation 737

Passenger cabin improvements, featuring more curved surfaces and larger overhead bins New airfoil section, increased wing span, area, and chord

Winglets on most models Redesigned vertical stabilizer Carbon brakes manufactured by Messier-BugattiThe design of Boeing 737-700 is in accordance with the airworthiness standards stated in

FAR Part 25 of the Federal Aviation Regulations issued by the Federal Aviation

Administration of the United States of America.


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Overall View

Fig 2.2 Boeing 737-700 with winglet

Boeing 737-700 DimensionsOverall Length 33.63 m

Height 12.57 m

Fuselage Diameter 3.76 m

Cabin Width 3.54 m

Cabin Height 2.20 m

Wing Span 34.31 m

Wing Area 124.6 m2

Wing Sweep 25.02 degrees

Aspect Ratio 9.45

Wheelbase 12.60 m

Wheel Track 5.72 m


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Fig 2.3 3-view of Boeing 737-700, -700C


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1.3 McDonnell Douglas MD-88

Fig 3.1 Delta Air Lines McDonnell Douglas MD-88 taking off from Ronald Reagan National Airport, Washington

The McDonnell Douglas MD-80 series are twin-engine, medium-range, single-aisle commercial

jet airliners. It was designed by McDonnell Douglas as an improved version of Douglas DC-9. In

comparison with the DC-9-50, MD-80 featured:

An increased wingspan

Larger fuselage Various aerodynamic improvements More fuel efficient engines Performance management system to optimise fuel efficiency and performance

The MD-80 series were built by Douglas and under license by the Shanghai Aviation IndustrialCorporation in China until production ended in 1999. MD-88 is an updated variant of MD-82

(variant for hot and high operations with 20,000 lb thrust JT8D-217 engines and increased

maximum takeoff weight) with glass cockpit, advanced EFIS cockpit displays and windshearwarning system.

The McDonnell Douglas MD-88 carries 152 passengers in 2-class configuration or 172

passengers in a single class over the range of 2050 nautical miles or 3800 kilometres.

The design of MD-88 follows the airworthiness standards of FAR Part 25 of the Federal

Aviation Regulations issued by the Federal Aviation Administration of the United States of

America.


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Overall View

Fig 3.2 MD-88 taking off from Fort Lauderdale-Hollywood International Airport

McDonnell Douglas MD-88 Dimensions

Overall Length 45.02 m

Height 9.05 m

Fuselage Diameter 3.35 m

Wing Span 32.87 m

Wing Area 112.3 m2

Wheelbase 22.05 m

Wheel Track 5.08 m


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Fig 3.2 3-view of MD-88


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2.0 Characteristics Table

A320-200 B737-700 MD-88

Manufacturer EADS Airbus Boeing Commercial

Airplanes

McDonnell Douglas

Role Narrow-body, short tomedium-range airliner

Narrow-body, short tomedium-range airliner

Narrow-body,medium-range airliner

Type of payload Main: Passenger

(+ cargo and light luggage)

Passenger capacity 2-class 1-class 150180 128148 142172

Cargo volume, m3 38.8 28.4 35.5

Fuel capacity, L 23860 26022 22129

Operating empty

weight, kg

42900 37648 35369

Payload weight, kg 19250 16505 16200

Max takeoff weight,

kg

77000 60328 67812

Max landing weight,

kg

64500 58060 58967

Cruise speed, km/h 900 955 811

Range (max pax),

km

5700 4400 3798

Max altitude, m 12500 12500 11200

Runway length, m 2400 2300 2600Power plant Engine type Engine thrust,

kN

2 XCFM56-5B

111-120

2 XCFM56-7B

108

2 XPW JT8D-217A/C

111-125

Consumption, L/h 2700 2770 3900


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3.0 Crew Size and Functions

Crew SizeAirbus A320-200 2 Flight crew

1 Captain 1 First officer

> 4 Cabin crew

Boeing 737-700 2 Flight crew 1 Captain 1 First officer

> 3 Cabin crew

McDonnell Douglas MD-88 2 Flight crew 1 Captain 1 First officer

>2 Cabin crew

Crew FunctionsCaptain

i. Ensures that a thorough inspection of the airplane and all equipment is properlyconducted.ii. Plans the mission by analyzing information, the expected weather over the mission route,

and special instruction.

iii. Prepares or supervises and coordinates the activities of the crew members during thepreparation of flight plan and clearance.

iv. Determines that the weight and center of gravity are within prescribed limits.v. Ensures that the passengers have been briefed on the location and operational use of

emergency equipment and are familiar with in-flight emergency signals and emergency

exits.vi. Operates controls to start and check engines, and to taxi, take-off, land and controls the

airplane in flight under varying conditions of weather, daylight and darkness, various-range missions.vii. Monitors operation of pressurization system to ensure safety of airplane and personnel.

viii. Directs the employment of navigational and communications equipment by the navigator,and copilot.

ix. Ensures that required flight logs, records and maintenance forms are prepared.First Officer

i. Assists the pilot in mission planning by obtaining pertinent weather forecast, intelligencereports, maps, and other documents.

ii. Assists navigator in piloting the mission route and calculating the route information andfuel requirements.iii. May perform inspections upon instructions of the pilot.

iv. Assists the pilot in operating controls and equipment on the ground and in flight.v. Operates the airplane on the ground and in flight upon instructions from the pilot.

vi. Prepares the flight log and required records and maintenance forms.vii. Operates the communications equipment and assists the pilot in navigating the airplane in

the absence of a navigator.

viii. Takes emergency procedure actions as required by the flight manual and/or the pilot.


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Cabin crew

i. Attend pre-flight briefing, during which air cabin crew members are assigned theirworking positions for the upcoming flight.

ii. Carry out pre-flight duties, including checking the safety equipment, ensuring the aircraftis clean and tidy, ensuring that information in the seat pockets is up to date and that all

meals and stock are on board.iii. Welcome passengers on board and direct them to their seats.iv. Inform passengers of the aircraft safety procedures and ensure that all hand luggage is

securely stored away.

v. Check all passenger seat belts and galleys are secured prior to take-off.vi. Make announcements on behalf of the pilot and answer passenger questions during the

flight.

vii. Serve meals and refreshments to passengers.viii. Sell duty-free goods and advise passengers of any allowance restrictions in force at their

destination.

ix. Reassure passengers and ensure that they follow safety procedures correctly inemergency situations.x. Give first aid to passengers where necessary.

xi. Ensure passengers disembark safely at the end of a flight and check that there is noluggage left in the overhead lockers.

xii. Complete paperwork, including writing a flight report.


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Ram Air SystemProvides cooling air for heat exchangers. Operation of the

system is automatically controlled by the packs throughoperation of ram air inlet.

Fig 4.1.2 Ram air inlet

Air Mix Valves

The two air mix valves for each pack control hot and cold air.

Air that flows through the cold

air mix valve is process througha cooling cycle and then

combined with hot air flowing

from the hot air mix valve.

Recirculation Fan

Reduces the air conditioningsystem pack load and the engine

bleed air demand. Air from the

passenger cabin and electrical

equipment bay is drawn to theforward cargo bay where it is

filtered and circulated to the mix

manifold.

Fig 4.1.3 Air Conditioning Pack Schematic


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Fig 4.1.4 Air Conditioning Distribution

Pressurisation System

Cabin pressurization is controlled during all phases of airplane operation by the cabin pressurecontrol system. The system uses bleed air supplied to and distributed by the air conditioning

system. Pressurisation and ventilation are controlled by modulating the outflow valve and the

onboard exhaust valve.

Pressure Relief Valves

Two pressure relief valves provide safety pressure relief by limiting the differential pressure to a

maximum of 9.1 psi. A negative relief valve prevents external atmospheric pressure fromexceeding internal cabin pressure.

Outflow ValveThe outflow valve is the overboard exhaust exit for the majority of the air circulated through the

cabin. Cabin air is drawn through foot level grills, down around the aft cargo compartment where

it provides heating, and is discharged overboard through the outflow valve.


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Fig 4.1.5 Pressurisation Outflow Schematic

Overboard Exhaust ValveOn the ground and in flight with low differential pressure, the

overboard exhaust valve is open and warm air from the E & E bay

is discharged overboard. In flight, at higher cabin differentialpressures, the overboard exhaust valve is closed and exhaust air is

diffused to the lining of the forward cargo compartment.The overboard exhaust valve is driven open if either pack switch isin high and the recirculation fan is off. This allows for increased ventilation in the smoke

removal configuration.


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[A320-200]

Avionics bay ventilation filtering systemSupplies the avionics compartment with dry, clean air while

aircraft is on the ground and in the air. The 2-stage system

offers a demister for water coalescene and a particulate filterfor dust removal.

Fig 4.1.6 Avionics bay ventilation filter developed by Donaldson

Electrical supply to ECS components on Airbus A320-200 is shown below:


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4.2 Passenger and Cargo Cabin Systems

Reason of use of Passenger and Cargo Cabin System:

To carry payload of passenger and cargoFunction of Passenger and Cargo Cabin System: Provide safety and comfort for passenger Provide sufficient cargo compartment4.2.1 Interior Layout

[A320-200]

Typical 2-class layout

Typical single-class layout

Single-class, high density layout

Basic bulk loading configuration


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Cargo loading system

Long-range compatible unit load devices


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[B737-700]

Cabin cross-section, 4-abreasts sitting

Cabin cross-sections, 6-abreast sitting


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4.2.2 Passenger Compartment Equipment

Passenger compartment seats

In low-cost carrier such as Air Asia, the

seat backrest cannot be reclined. Someairliners offer in-seat audio and video

entertainment at the passenger

compartment seats.Typical arrangement of seats in a row is

3+3.

Fig 4.2.1 Air Asia A320 economy seats

Fig 4.2.2 First class seats of Air Canada

Aircraft Class Seat Pitch Seat Width Seat Recline

A320-200 First 36 21 21.5 5

Economy 33 35 17.8 18 4.5

B737-700 First 38 21 7.5

Economy 31 17.2 3

MD-88 First 37 19.5 n/a

Economy 31 33 17 n/a

Cabin attendant seats

Also known as jump seats, they are placed near emergency doors and have a shoulder harnessand a seat belt. Cabin attendant seats are usually attached to the walls of the galleys or lavatories

or mounted on the floor of the passenger compartment. The seat bottom can be folded verticallyfor storage.


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Overhead storage compartmentsProvides space for passengers carry-on luggage.

Fig 4.2.3 Overhead storage compartment of A320-200

Fig 4.2.4 Overhead storage compartment of B737-700

Passenger service units (PSU)

Features reading lights, steward call indicators,information sign (such as no smoking and fasten seat

belts), loudspeaker, seat and row number indicator,

digital interface to cabin intercommunication datasystem

Fig 4.2.5 A320s PSU manufactured by Goodrich Corporation

GalleysThe galley is the compartment where

food is cooked and prepared. It includes

not only facilities to serve and storefood and beverages, but also contain

cabin attendant seats, emergency

equipment storage, as well as anythingelse flight attendants may need during

the flight.

Fig 4.2.6 Bcher G6 aft galley installed in A320


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Fig 4.2.7 G4B galley manufactured by Driessen for B737-700

Fig 4.2.8 G1 galley manufactured by Driessen for B737-700


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BafflesAlso known as class dividers, it is used to separate

different class of passenger seats

Fig 4.2.9 B737 baffle manufactured by Composites Unlimited

Lavatory

Modern lavatories uses vacuum flush and mostly have safetyfeatures including smoke detectors, waste receptacle portable fire

containment halon extinguishing bottles and oxygen-smothering

flapper lids fitted to the hand towel waste disposal receptacles.

Fig 4.2.10 A320 Lavatory manufactured by Dasell Cabin Interiors

Fig 4.2.11 Position of galley (G) and lavatory (L)


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4.2.3 Water and Waste System

Functions:

Distribute portable water to the toilets and the galleys Disposes waste water Stores toilet wastesThe system is insulated to prevent water leaks and ice build-up.

[A320-200]

Potable water

Potable water is stored in a 200L tank infront of the wing box behind the forward

cargo compartment. While airborne, the

airplane uses bleed air to pressurize the water

system; on the ground, it uses air from theservice panel pressure port. Potable water is

piped to galleys and lavatories.

Wastewater systemWastewater from galleys and sinks in

lavatories drains overboard through 2 anti-icemasts. The forward mast drains from the

forward cabin while the aft mast drains from

the aft cabin. Differential pressure discharges

the wastewater in flight and gravity does soon the ground.


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Toilet systemDifferential pressure forces waste from the toilet

bowls into the waste storage tank. On ground, andat altitudes >16000 feet, a vacuum generator

produces the necessary pressure differential. Clear

water from the potable water flushes the toilets. Aflush control unit, within each toilet, controls the

flush sequence. The waste tank has a usable

capacity of 170L.

The waste and water system in A320-200 is connected to the electrical supply system by:


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4.3 Crew Compartment Equipment

Reason of use of Crew Compartment Equipment:

Area where the pilot controls the airplaneFunction of Crew Compartment Equipment: Contains flight instruments, and the controls which enable the pilot to fly the aircraft. Increase pilot situation awareness without causing information overload[A320-200]

Cockpit plan

The cockpit can accommodate twocrewmembers, plus a third

occupant. The 2 pilot seats are

mounted on columns while the 3rdoccupant seat is a folding seat.

Fig 4.3.1 Top view of cockpit


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Pilot seatsA pilot seat can be adjusted

mechanically or electrically. Armrestand headrest can also be adjusted to

provide comfort and to enhance

performance.

There is storage for briefcase and life jacketat the back of the pilot seat.


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Cockpit windowsThe cockpit has fixed and

sliding windows. Sliding

windows are used asemergency exits for the pilot.

Pilots instrument panel

1. An optimised layout of six LCD (Liquid Crystal Display) screens ensures that the two-personcrew can easily assimilate all relevant data.

EFIS displays, for flight information ECAM displays, for systems, engine and warnings information All six LCDs are interchangeable, functionally and by part number

2. The absence of heavy, bulky control columns between the pilots and their instrumentsensures an unimpeded view.

3. Two Multipurpose Control and Display Units (MCDU) on the pedestal, in addition toaccessing the Flight Management System (FMS), are used to give systems maintenance data,

in the air and on the ground, upon request.

4. The system is coupled to a printer and can also be coupled to an optional AircraftCommunication Addressing and Reporting System (ACARS) link.

5. Real time flight and systems data are displayed to the pilots on 6 LCDs.


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6. Flight information is provided by the Electronic Flight Instrument System (EFIS) comprisingof Primary Flight Display (PFD) and Navigation Display (ND) in front of each pilot.

7. System information is provided by the Electronic Centralised Aircraft Monitor (ECAM)comprising of engine instrumentation and warnings on the upper screen, and aircraft systems

on the lower screen.

8.

Features Integrated Stand-by Instrumentation System (ISIS) on one additional LCD screen.

Fig 4.3.3 Pilots instrument panel


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PedestalIt is located between the Captain and the First Officer.

Overhead panel

The panel is located above and in between the Captain and the First Officer.


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Cockpit visibilityDuring flight, pilot must have good visibility from the cockpit. The pilot can view approximately

15 metres in front from the cockpit. The pilot have a visibility angle of 33 degrees abovehorizontal and 20 degrees below horizontal. The pilot is also able to see the wingtip of his of the

airplane which is a desirable aspect.


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Electrical supply to the cockpit is as follows:


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4.4 Hydraulic Systems

The reason of use of Hydraulics Systems:

An efficient way of transferring power from small low energy movements in the cockpit tohigh energy demands in the aircraft

The function of Hydraulics Systems:

Assist the operator in a accomplishing a mechanical task that requires a great amount of work Used to power brakes, flight controls, leading edge flaps and slats, trailing edge flaps,

landing gears, nose wheel steering, thrust reversers, and autopilots

[A320-200]

Airbus A320-200 has 3 continuously operating hydraulic systems: blue, green and yellow. Each

system has its own hydraulic reservoir. Normal system operating pressure is 3000 psi. Hydraulic

fluid cannot be transferred from 1 system to another.

Green system pumps

A pump driven by engine 1 pressurises the green system.

Blue system pumpsAn electric pump pressuries the blue system. A pump driven by ram air turbine (RAT)

pressurizes this system in an emergency

Yellow system pumps

A pump driven by engine 2 pressurises the yellow system. An electric pump can also pressurize

the yellow system, which allows yellow hydraulics to be used on the ground when the enginesare stopped. Crew members can also use a hand pump to pressurise the yellow system in order to

operate the cargo doors when no electrical power is available.

Power transfer unit (PTU)

A bidirectional power transfer unit enables the yellow

system to pressurize the green system and vice versa.The power transfer unit operates automatically when

the differential pressure is between the green and the

yellow systems is >500 psi. The PTU therefore allowsthe green system to be pressurised on the ground

when the engines are stopped. Fig 4.4.1 PTU manufactured by Eaton

Ram air turbine (RAT)A drop-out RAT coupled to a hydraulic pump allows the blue system to function if electrical

power is lost or both engines fail. The RAT deploys automatically if AC BUS 1 and AC BUS 2

are both lost. It can be deployed manually from the overhead panel. It can be stowed only when

the aircraft is on the ground.


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System accumulatorsAn accumulator in each system helps to maintain a

constant pressure by covering transient demandsduring normal operation.

Priority valvesPriority valves cut off hydraulic power to heavy load users if hydraulic pressure in a system gets

low.

Fire shutoff valves

Each of the green and yellow systems has a fire shutoff valve in its line upstream of its engine-

driven pump. The flight crew can close it by pushing the ENG 1(2) FIRE pushbutton.

Leak measurement valves

Each system has a leak measurement valve upstream of the primary flight controls. These valvesmeasure the leakage in each circuit.

FiltersFilters clean the hydraulic fluid as follows:

HP filters on each system and on reservoir filling system and the normal braking system Return line filters on each line Case drain filters on engine pumps and the blue electric pump (which permit maintenance

to monitor engine wear by inspecting the filters for presence of metallic particles)


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Fig 4.4.2 Generation of hydraulic system

Reservoir pressurizationNormally, HP bleed air from engine 1 pressurises the hydraulic reservoirs automatically. If the

bleed air pressure is too low, the system takes air pressure from the crossbleed duct. The systems

maintain a big enough pressure to prevent their pumps from cavitating.

Fig 4.4.3 Reservoir pressurisation schematic


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Energy supply of hydraulic system is shown as below:

Interaction of hydraulics system (blue, yellow and green) with flight control systems is shown in

the figure below.

Fig 4.4.5 Flight control schematic


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[B737-700]

Boeing 737-700 has 3 hydraulic systems: A, B and standby. Either A or B hydraulic system canpower all flight controls with no decrease in airplane controllability. Each hydraulic system has a

fluid reservoir located in the main wheel well area. System A and B reservoirs are pressurised by

bleed air. The standby system reservoir is connected to system B reservoir for pressurisation andservicing. Pressurisation of all reservoirs ensures positive fluid flow to all hydraulic pumps.

A and B hydraulic system pumps

Both A and B hydraulic systems have an engine-driven pump and an AC electric motor-driven

pump. The system A engine pump is powered by

No.1 engine while system B engine-driven pumpis powered by the No.2 engine. An engine-driven

hydraulic pump supplies approximately 4 times

the fluid volume of the related electric motor-

driven hydraulic pump.Hydraulic fluid used for cooling and lubrication

of pumps passes through a heat exchanger before

returning to the reservoir. The heat exchanger forsystem A is located in the main fuel tank No.1

and for system B is in the main fuel tank No.2

Power transfer unitThe purpose of PTU is to supply additional volume of hydraulic fluid needed to operate the

autoslats and leading edge flaps and slats at the normal rate when system B engine-drivenhydraulic ump volume is lost. The PTU uses system A pressure to power a hydraulic motor-

driven pump which pressurizes system B hydraulic fluid. The PTU operates automatically when

all the condition exists: system B engine-driven pump hydraulic pressure drops below limits airborne flaps are less than 15 but not up flaps not up

Landing gear transfer unit

Its purpose is to supply the volume of hydraulic fluid needed to raise the landing at the normalrate when system A engine-driven pump volume is lost. The system B engine driven pump

supplies the volume of hydraulic fluid needed to operate the landing gear transfer unit when all

of the following condition exist: airborne No.1 engine RPM drops below a limit value landing gear is lever is positioned UP either main landing gear is not up and locked


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4.5 Pneumatic Systems

Reason of use of pneumatic system:

Pneumatic system uses incompressible air which is lighter than hydraulic fluid Compressed air does not present temperature-related problems No fire hazard is associated with compressed airFunction of pneumatic system:

The pneumatic system supplies high-pressure air for air conditioning, enginer starting, winganti-icing, water pressurization and hydraulic reservoir pressurization.

[A320-200]

Fig 4.5.1 Position of pneumatic system denoted by P

High-pressure air has 3 sectors: engine bleed systems, APU load compressor and HP ground

connection.

Engine bleed system

The aircraft has two similar engine bleed air systems which are designed to select the compressor

stage to use as a source of air, regulate the bleed air temperature and regulate the bleed airpressure.

Air is normally bled from the intermediate pressure stage (IP) of engines high pressure (HP)

compressor to minimize fuel penalty. At low engine speed, the system bleeds air from the HPstage and maintains it at 36 + 4 psi. An intermediate pressure check valve downstream of the IP

port closes to prevent air from the HP stage from being circulated to IP stage.


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Bleed Monitoring Computer (BMC)A Bleed Monitoring Computer controls and

monitors each engine bleed system. Each BMCreceives information about bleed pressure and

temperature and valve position. The BMC

supplies indications and warnings to ECAM andCFDS (from crew compartment equipment).

Bleed valve

The bleed valve, which is downstream of thejunction of HP and IP ducting, acts as a shut-off

and pressure regulating valve. It maintains

delivery pressure at 44 + 4 psi. Each bleed valveis pneumatically operated and controlled

electrically by its associated BMC.

Fig 4.5.2 Liebherr's Bleed Valves on A320 engine

PrecoolerA precooler downstream of the bleed

valve regulates the temperature of the

bleed air. The precooler is an air-to-airheat exchanger that uses cooling air bleed

from the engine fan to limit thetemperature to 200

oC. The fan air valve

controls fan air flow.

Fig 4.5.3 Donaldsons air-cooled precooler

APU bleed air supplyAir from the APU load compressor is available on the ground and in flight. The APU bleed valve

operates as a shut-off valve to control APU bleed air. APU bleed air supplies the pneumaticsystem if the APU speed is above 95%. This opens the crossbleed valve and closes the engine

bleed automatically. A check valve near the crossbleed duct protects the APU when bleed aircomes from another source.

CrossbleedA crossbleed valve on the crossbleed duct allows the air supply systems of the 2 engines to be

isolated or interconnected. A rotary selector of the AIR COND panel controls the crossbleedvalve electrically. 2 electric motos control the valve.


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Leak detectionLeak detection loops detect any overheating near the hot air ducts in the fuselage, pylons and

wings. For the pylon and APU, the sensing elements are tied to form a single loop and for thewing, a double loop. When the 2 wing loops detect a leak, they activate a wing leak signal.

Electrical supply to pneumatic system is shown as below:


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4.6 De-icing and Anti-icing Systems

Reason of use of De-icing and Anti-icing Systems:

Aircraft flies at high altitude which low temperature can induce formation of ice Formation of ice on the wing reduces lift Large pieces of ice can be ingested into turbine engines or impact moving propellers and

cause failure

Function of De-icing and Anti-icing Systems:

De-icing system removes ice formed on the surface Anti-icing system prevents formation of ice

[A320-200]

Fig 4.6.1 Anti-ice and anti-rain systems

Wing anti-iceIn flight, hot air from the pneumatic systems heats the 3 outboard slats of each wing. Air is

supplied through one valve in each wing.

Engine anti-iceAn independent air bleed from the high pressure compressor protects each engine nacelle from

ice. Air is supplied through a 2-position valve that the flight crew controls with 2 buttons, 1 foreach engine.


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Fig 4.6.2 Wing anti-ice heating slats 3-4-5

Window heatA320 uses electrical heating for anti-icing each windshield and demisting the cockpit side

windows. 2 independent Window Heat Computers, one on each side, automatically regulate the

system, protecting it against overheating and indicate faults.

Window heating comes on automatically when at least 1 engine is running or when the aircraft isin flight. It also comes on manually before the start of engine when the flight crew switches on

the Probe/Window Heat pushbutton.Windshield heating operates at low power in the ground and at normal power in flight. Only one

heating level exists for the windows.


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Fig 4.6.3 Window heatschematic

Probes heatElectrical heating protects pitot heads, static ports, angle-of-attack probes and total air

temperature probes. 3 independent Probe Heat Computers automatically control and monitor

captain probes, F/O probes and STBY probes. They protect against overheating and indicatefaults.

Visual ice indicatorAn ice detection system. The external visual ice indicator is installed between the 2 windshields.

The indicator has also a light.


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The energy supply to anti-icing system on A320-200 is as follows:


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4.7 Emergency Systems

Reason of use of Emergency Systems:

No matter how well the designing and manufacturing process, some systems will inevitably fail

or malfunction. Emergency systems are designed to cater for such failures.

Function of Emergency Systems:

Inform crew that something is wrong or malfunction Allow crew to perform corrective action such as to provide alternative means of control or

safe evacuation

Fig 4.7.1 Emergency systems location on BAC 111


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[B737-700]

4.7.1 Warning System

Warning lights

Conditions which require immediate action are indicated by red warning lights located in thearea of the pilots primary field of vision. These lights indicate engine, wheel well, cargo, or

APU fires; autopilot, autothrottle disconnects; and landing gear unsafe conditions.

Conditions which require timely attention of flight crew are indicated by amber caution lights.

Blue lights inform the flight crew of electrical power availability, valve position, equipment

status, and flight attendant or ground communications. Blue lights are for information and do not

require immediate flight crew attention.Green lights indicate a fully extended configuration, e.g. landing gear and leading edge devices.

2 Master Fire Warning Lights illuminate when any fire condition occurs.2 Master Caution Lightilluminate when any caution occurs outside the normal field of vision of

the flight crew.

2 System Annunciator Lights are located on the glare shield. They include only systems locatedin the forward, aft overhead and fire control panels.

Fig 4.7.2 Master Caution and System Annunciator lights

Stall warningStall warning is provided by a control column shaker on each control column. The stall warning

stick shaker consists of 2 eccentric weight motors. They alert the pilots before a stall developsThe warning is given by vibrating both control columns.

Aural signals

Various aural signals call attention to warnings and cautions. An aural warning for airspeedlimits is given by a clacker, the autopilot disconnect by a warning tone, takeoff configuration and

cabin altitude by an intermittent horn, and landing gear position by a steady horn. The fire

warning by afire warning bell. Ground proximity warnings and alerts, and windshear warningsand alerts are given by voice warnings.


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Proximity Switch Electric Unit (PSEU)The PSEU monitors takeoff configurations warnings, landing

configurations warnings, landing gear warnings, and air/groundsensing. The PSEU, its sensors and its input signals are

monitored for internal faults. When designated faults are

detected, PSEU light on the aft overhead panel illuminates andthe OVERHEAD system annunciator light and MASTER

CAUTION lights illuminate.

Traffic Alert and Collision Avoidance System (TCAS)TCAS alerts the crew to possible conflicting traffic. TCAS

interrogates operating transponders in other airplanes,

tracks the other airplanes by analyzing the transponderreplies and predicts the flight paths and positions. TCAS

provides advisory and traffic displays of the other airplanes

to the flight crew.

Ground proximity alertsThe ground proximity warning system (GPWS) provides

alert for potentially hazardous flight conditions involvingimminent impact with the ground. The GPWS monitors

terrain proximity using an internal worldwide terrain

database. Proximate terrain data shows on the navigationdisplay. Alerts are based on estimated time to impact.

These alerts are look-ahead terrain alerts. The GPWS

provides alerts based on radio altitude and combinations of

barometric altitude, airspeed, glide slope deviation, andairplane configuration.


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4.7.2 Fire Protection

Engine overheat and fire detectionAs the temperature of a detector increases to a predetermined limit, the detector senses an

overheat condition. At higher temperatures, the detector senses a fire condition. The indications

of an engine fire are the fire warning bell sounds, both master FIRE WARN lights illuminate, therelated engine fire warning switch illuminates, and all related engine overheat alert indications

illuminate.

Engine fire extinguishingConsists of 2 engine fire extinguisher

bottles, 2 engine fire warning switches, 2BOTTLE DISCHARGE lights and an

EXT TEST switch. Either or both bottles

can be discharged into either engine.

Fig 4.7.3 Engine fire bottles

APU fire detection

As the temperature of the detector increases to a predetermined limit, the detector senses a fire

condition. The indications of an APU fire are

the fire warning bell sounds, both master FIREWARN lights illuminate, the APU fire warning

switch illuminates, the APU automatically shuts

down, the wheel well APU fire warning hornsounds, and the wheel well APU fire warning

light flashes

APU fire extinguishingConsists of 1 APU fire extinguisher bottle, an

APU fire warning switch, an APU BOTTLE

DISCHARGE light, and EXT TEST switch.The APU ground control panel located in the

right main wheel well also contains an APU fire

warning light, an APU BOTTLE DISCHARGEswitch, an APU fire control handle and APU

HORN CUTOUT switch.

Fig 4.7.4 APU ground control panel


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Main wheel well fire protectionMain wheel well fire protection consists of fire detection powered by the No.2 AC transfer bus.

As the temperature of the detector increases to a predetermined limit, the detector senses a firecondition. The indications of a main wheel well fire are the fire warning bell sounds, both master

FIRE WARN lights illuminate, and the WHEEL WELL fire warning lights illuminates. The

main wheel well has no fire extinguishing system. The nose wheel well does not have a firedetection system.

Cargo compartment smoke detection

The forward and aft cargo compartments each havesmoke detectors in a dual loop configuration.

normally each loop must sense smoke to cause an

alert. These loops function in the same manner asthe engine overheat/fire detection loops.

Fig 4.7.5 Cargo hold smoke detector

Cargo compartment fire warning

The indications of a cargo compartment fire are the fire warning bell sounds, both master FIRE

WARN lights illuminate, and the FWD/AFT cargo fire warning lights illuminates.

Cargo compartment fire extinguishing

A single fire extinguisher bottle is installed in the air conditioning mix bay on the forward wingspar. Detection of a fire in either forward or aft compartment will cause the FWD or AFT cargo

fire warning light to illuminate. Once armed and discharged, the contents of the bottle will be

totally discharge into selected compartment.

Lavatory smoke detectionThe lavatory smoke detection system monitors for the presence of smoke. When smoke is

detected, an aural warning sounds; the red alarm indicator light on lavatory smoke detector panelilluminates and the appropriate amber lavatory call light will flash; and the amber lavatory

SMOKE light on the forward overhead panel illuminates.

Lavatory fire extinguisher systemA fire extinguisher system is located beneath

the sink area in each lavatory. When fire isdetected, fire extinguisher operation is

automatic and flight deck has no indication

of extinguisher discharge.


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4.7.3 Passenger Evacuation

Evacuation slideAn inflatable slide that is placed at emergency doors and is

used to evacuate an aircraft quickly. The slide operates

automatically or manually and inflate rapidly so thatpassengers can slide to the ground. Doors are designed to

open outwards and are of sufficient to allow passengers to

exit rapidly.

[A320-200]

4.7.4 Emergency Oxygen

The oxygen system supplies adequate breathing oxygen to the crew and passengers in case of

depressurization or presence of smoke or toxic gas.

Cockpit fixed oxygen systemConsists of: A high-pressure cylinder, in the left-hand lower fuselage A pressure regulator, connected directly to the cylinder that delivers oxygen at a pressure

suitable for users 2 overpressure safety systems to vent oxygen overboard through a safety port if the pressure

gets too high A supply solenoid valve that allows the crew to shut off the distribution system 3 (or 4) full-face quick donning masks, stowed in readily-accessible boxes adjacent to the

crew members seats

The crew member squeezes the red grips to pull out the mask out of its box. A mask-mountedregulator supplies a mixture of air and oxygen or pure oxygen, or performs emergency pressure

control. The storage box contains a microphone lead with a quick-disconnect for connection tothe appropriate mask microphone cable.


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Fig 4.7.6 Crew oxygen mask

Fig 4.7.7 Pressure regulator mounted at the mask

Fixed oxygen system for cabin

Supplies oxygen to passengers in case of cabin depressurization.Chemical generators produce the oxygen. Each generators feed a

group of masks. Generators and masks are in the passenger service

units, in the lavatories, in each galley, and at each cabin crew station.Each container has an electrical latching mechanism that opens

automatically to allow the masks to drop if cabin pressure altitude

exceeds 14000 feet. The generation of oxygen begins when the user pull the mask towards the passenger seat. The chemical used for

oxygen generation creates heat. Therefore, the smell of burning or

smoke and cabin temperature increase is expected. The maskreceives pure oxygen under positive pressure for 15 minutes.


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Flight crews portable oxygen systemThe smoke hood on the left back side of the cockpit protects the eyes and respiratory system of

one member of the flight crew while he is fighting a fire, or if smoke enters the cabin, or if cabinloses pressure. The smoke hood uses a chemical air regeneration system. An orosnasal mask

allows the hoods wearer to inhale regenerated air, and it returns the exhaled breath to the

regeneration system. The hood last for 20 minutes.


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Electrical supply to A320-200s oxygen system and fire protection system is shown below:

Oxygen system

Fire protection system


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4.8 Engine Control Systems

Reason of use of engine control systems:

Aircraft flies at wide range of forward speeds, altitudes and temperatures. Hence, fuel flow and

air flow to the engine must be controlled to allow the engine to operate at its optimum efficiency.

Modern engine control systems allow the pilot to perform carefree handling of the enginethroughout flight envelope thus reducing crew workload.

Function of engine control systems:

Fuel flow to allow varying engine speeds to be demanded and to allow the engine to behandled without damage by limiting rotating assembly speeds, rates of acceleration, and

temperatures

Air flow to allow the engine to be operated efficiently throughout the aircraft flightenvelope and with adequate safety margin

Exhaust gas flow by burning the exhaust gases and varying the nozzle area to provideadditional thrust

[A320-200]

Airbus A320-200 uses 2 CFM 56-5B engines, one on each wing. The CFM 56-5B is high bypassratio turbofan engine.

Fig 4.8.1 CFM 56-5B engine schematic


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Low-pressure (LP)

compressor/turbine

The low-speed rotor (N1) consists of a front fan (single-stage) and

a four-stage LP compressor connected to a four-stage LP turbine

High-pressure (HP)

compressor/turbine

The high-speed rotor (N2) consists of a nine-stage HP compressorconnected to a single-stage HP turbine

Combustion chamber The annular combustion chamber is fitted with 20 fuel nozzles

and 2 ignitersAccessory gearbox Located at the bottom of fan case. Receives torque from

horizontal HP rotor drive shaft and drives gearbox mounted

accessories

Full Authority Digital Engine Control (FADEC)

Each powerplant has a Full Authority Digital Engine Control (FADEC) system. FADEC, alsocalled the Electirc Control Unit (ECU), is a digital control system that performs complete engine

management. FADEC has two-channel redundancy, with one channel active and one in standby.

If one channel fails, the other automatically takes control. The system has a magnetic alternator

for an internal power source. FADEC is mounted on the fan case. The Engine Interface Unit(EIU) transmits to FADEC the data it uses for engine management.

The advantages of using FADEC are: Substitution of hydromechanical control system reduced weight and fuel burn Increased automation reduced pilot workload Optimised engine control reduced maintenance cost

FADEC lowers cost and increases engine life.

Fig 4.8.2 Goodrichs FADEC for Airbus A320


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Fig 4.8.3 FEDAC schematic


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Functions of FADEC:

Control of gas generator Control of fuel flow

Acceleration and deceleration schedulesVariable bleed valve and variable stator vane

schedules

Control of turbine clearanceIdle setting

Protection against engine exceeding

limits

Protection against N1 and N2 overspeed

Monitoring of EGT during engine start

Power management Automatic control of engine thrust ratingComputation of thrust parameter limits

Manual management of power as a function of thrust

lever positionAutomatic management of power (A/THR demand)

Automatic engine starting sequence Control of: the start valve (on/off)

the HP fuel valve the fuel flow the ignition (on/off)

Monitoring of N1, N2, FF, EGTInitiation of abort and recycle (on the ground only)

Manual engine starting sequence Passive monitoring of engine

Control of: the start valve the HP fuel valve the ignition

Thrust reverser control Actuation of the blocker doors

Engine setting during reverser operationFuel recirculation control Recirculation of fuel to the fuel tanks according to

the engine oil temperature, the fuel systemconfiguration and the flight phase

Transmission of engine parameters

and engine monitoring information to

cockpit indicators

The primary engine parameters

The starting system statusThe thrust reverser system status

The FADEC system status

Detection, isolation and recording of

failures

FADEC cooling


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Electrical supply to FADEC and EIU is shown below:


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4.9 Flight Control Systems

Reason of use of flight control systems:

Enable the pilot to exercise control over the aircraft during all portions of flightFunction of flight control systems: Provide stable control for all parts of the aircraft flight envelope Control the high-lift devices required during approach and landing phases of flight Provide the pilot with artificial feel so that the pilot is able to control the aircraft comfortably Reduce pilot workload[A320-200]

Airbus is the first aircraft manufacturer to introduce Fly-By-Wire (FBW) to civil transport. The

advantages of using FBW system are it incorporates flight envelope protection, reduces costs,reduces pilot workload and improves aircraft performance.

The flight control surfaces are all hydraulically powered and are electrical or mechanical

controlled:

Electrical control Mechanical control

Elevators (2) Rudder

Ailerons (2) Tailplane trim (reversionary mode)Roll spoilers (8)

Tailplane trim (1)

Slats (10)

Flaps (4)Speedbrakes (6)

Lift dumpers (10)

Trims


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Fig 4.9.1 Flight control schematic. The blue, yellow and green hydraulics systems power the flight control actuators.

Cockpit controls

2 sidestick controllers (1 for each pilot) with which to exercise manual control of pitch androll. These are on their respective lateral consoles. The 2 sidestick controllers are not coupledmechanically and they send separate sets of signals to the flight control computers.

2 pairs of pedals, which are rigidly interconnected, give the pilot mechanical control of therudder.

Control speed brakes, controlled with a lever on the centre pedestal Mechanically interconnected handwheels, which are on each side of the centre pedestal,

control the trimmable horizontal stabilizer.

A single switch on the centre pedestal to set the rudder trim.

Fig 4.9.2 Sidestick


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ComputersSeven flight control computers process pilot and autopilot inputs according to normal, alternate

or direct flight control laws.

2 Elevator Aileron Computer (ELACs) Normal elevator and stabilizer control

Aileron control3 Spoilers Elevator Computer (SECs) Spoilers control

Standby elevator and stabilizer control

2 Flight Augmentation Computer (FACs) Electric rudder control

In addition 2 Flight Control Data Connectors (FCDC) acquire data from the ELACs and SECs

and send it to the electronic instrument system (EIS) and the centralized fault display system

(CFDS).

Pitch control

2 elevators and the Trimmable Horizontal Stabiliser (THS) control the aircraft in pitch. Themaximum elevator deflection is 30 degrees nose up and 17 degrees nose down. The maximumTHS deflection is 13.5 degrees nose up and 4 degrees nose down.


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Roll control

One aileron and 4 spoilers on each wing control the aircraft about the roll axis. The maximum

deflection of aileron is 25 degrees. The ailerons extend 5 degrees down when the flaps are

extended (aileron droop). The maximum deflection of the spoilers is 35 degrees.

Yaw control

One rudder surface controls yaw. The yaw damping and turn coordination functions are

automatic. The ELACs compute yaw orders for coordinating turns and damping yaw oscillations

and transmit them to the FACs. The pilots can use conventional rudder pedals to control rudder.


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Flaps and slatsEach wing has 2 flap surfaces and 5 slat surfaces. These surfaces are electrically controlled and

hydraulically operated.


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Electrical supply to the flight control systems are shown as below:


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4.10 Landing Gear Systems

Reason of use of landing gear systems:

Landing gear is used for landing and ground manoeuvring of the aircraft. Without landing gears,

an aircraft will not be able to land on the runway and potential damage would occur on the

aircraft body.

Function of landing gear systems:

To absorb landing shocks and taxiing shocks To provide ability for ground manoeuvring: taxi, take-off roll, landing roll and steering To provide for braking capability To allow for airplane towing To protect the ground surface[A320-200]

Fig 4.10.1 Position of landing gears

The landing gear of A320-200 consists of two main gears that retract inboard and a nose gear

that retracts forward. Doors enclose the landing gear bays. Gear and doors are electricallycontrolled and hydraulically operated. The doors which are fitted to the landing gear struts areoperated mechanically by the gear and close at the end of retraction. 2 Landing Gear Control and

Interface Units (LGCIUs) control the extension and retraction of landing gear and operation of

the doors. They also supply information about the landing gear to ECAM for display and send

signals indicating whether the aircraft is in flight or on the ground to other aircraft systems.

Fig 4.10.2 Landing gear footprints


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Main gearEach main gear has twin wheels and an

oleopneumatic shock absorber. Each mainwheel has an antiskid brake.

Nose gearThe two-wheeled nose gear has anoleopneumatic shock strut and a nose wheel

steering system.

Nose wheel steeringA hydraulic actuating cylinder steers the nose wheel. Thegreen hydraulic system supplies pressure to the cylinder and

electric signals from the Brake and Steering Control Unit

(BSCU) controls it. BSCU receives orders from the Captainsand the First Officers steering hand wheels, the rudder pedals,

or the autopilot.

Fig 4.10.3 Steering handwheel


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Brakes

The main wheels have multidisc brakes that can be actuated by either of two independent brake

systems. The normal system uses green hydraulic pressure while the alternate system uses theyellow hydraulic system backed up by a hydraulic accumulator. Braking commands come form

either the brake pedals or the auto brake system. All braking functions are controlled by a 2-

channel BSCU. There are four modes of operation; normal braking, alternate braking with anti-skid, alternate braking without anti-skid and parking brake.

Fig 4.10.4 Goodrich carbon brakes and wheels

Anti-skid systemProduces maximum braking efficiency by maintaining wheels just short of an impending skid.

When a wheel is on the verge of locking, the system sends brake release orders to the normal and

alternate servo valves.

Auto brake

The purposes of this system are: to reduce the braking distance in case of an aborted takeoff to establish and maintain a selected deceleration rate during landing, thereby improving

passenger comfort and reducing crew workload

Parking brake

Brakes are supplied by yellow hydraulic system or accumulator via the dual shuttle valves.

Alternate servo valves open allowing full pressure application. The accumulator maintains theparking pressure for at least 12 hours.

Fig 4.10.4 Brake hydraulic accumulator


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Tyre pressure indicating systemIncludes a sensor that measure the pressure of each tyre, a transmission unit that transmits the

electrical pressure signal from the sensor to the computer, and a tyre pressure indicating unitcomputer that sends information to the ECAM for cautions and the system page display.

The size and pressure of each tyre are shown below:


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Electrical supply to the landing gear is shown below:

As observed, landing gear systems require close interaction with the hydraulics system. Greenhydraulic system actuates all gear and doors. Yellow hydraulic system supplies the parking

brakes.


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5.0 Reference

Technical Informationwizzair.com/about_us/fleet

www.gear-up.ch/miscstuff_02.htm

www.prospects.ac.uk

General SubsystemsESA 371 Lecture Notes, Prof Vladimir ZhuralevAirplane Design Part IV: Layout Design of Landing Gear and Systems, 1989, Dr. Jan RoskamAdvanced Aircraft Systems, 1993, David LambardoAircraft Systems: Mechanical, Electrical, and Avionics Subsystems Integration, 2001, Ian Moir, Allan

Seabridge737 Airplane Characteristics for Airport Planning, October 2005A320 Airplane Characteristics for Airport Planning, July 1995MD-80 Series Airplane Characteristics for Airport Planning,1990Airbus A320 Technical Appendices

Airbus A320 Flight Crew Operating Manualwww.smartcockpit.comwww.b737.org.uk/aircraftsystems.htmwww.airframer.com/aircraft_detail.html?model=A320www.wikipedia.org

Passenger Cabin Systemswww.kennysia.comwww.seatguru.com

www.continental.com/web/en-US/content/travel/default.aspxwww.delta.com/planning_reservations/plan_flight/aircraft_types_layout/index.jspwww.sizewise.com/docs/skies.html

www.aircanada.com/en/about/fleet/a320-200xm.htmlwww.planebuzz.com/2008/04

a320cabinmod.blogspot.comwww.gecas.com/pdf/B737-700.pdf

www.compositesunlimited.com/samples.htmlwww.dasell.comwww.goodrich-lighting.com/catalog/Chapter02_Passenger_Service_Units

Hydraulic Systemswww.eaton.com

www.donaldson.com

passenger aircraft subsystems

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