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AIRCRAFT GENERAL


ABBREVIATIONS

TE: training edgeTYP: typicalVHF: very high frequencyVLV: valveWL: water line

GENERAL DIMENSIONS OF THE AIRPLANE:

737- Structure dimensions


General:

Dimensions give locations on the fuselage. The scale for each dimension isinches. You use these dimensions to find components on the fuselage.

Body station line, body buttock line, water line.

The body station line (STA) is a horizontal dimension. It starts at station linezero. You measure the body station line from a vertical reference plane that isforward of the airplane.

The body buttock line (BL) is a lateral dimension. You measure the buttock lineto the left or right of the airplane centre line.

The water line (WL) is a height dimension. You measure the water line from ahorizontal reference plane below the airplane.

737- Fuselage dimensions


Wing reference dimensions:

The wing has two reference dimensions. These reference dimensions give winglocations in inches. Measure each location from buttock line 0.These are wing reference dimensions:

Wing stationWing buttock line

You measure the wing station perpendicular to the wing leading edge.

You measure the wing buttock line parallel to the buttock line.

737- Wing reference dimensions


Vertical stabilizer reference dimensions:

The vertical stabilizer has four reference dimensions. These referencedimensions give vertical stabilizer locations in inches. These are verticalstabilizer reference dimensions:

Vertical stabilizer stationVertical stabilizer leading edge stationRudder stationVertical stabilizer waterline

Measure the vertical stabilizer station perpendicular to the vertical stabilizer rearspar. Vertical stabilizer station 0 starts at the body crown line.

Measure the vertical stabilizer leading edge station perpendicular to the verticalstabilizer leading edge. Vertical stabilizer leading edge station 0 starts at thebody crown line.

Measure the rudder station perpendicular to the rudder hinge centreline. Rudderstation 0 starts at the body crown line.

Measure the vertical stabilizer waterline parallel to the body waterline.

737- Vertical stabilizer reference dimensions


Horizontal stabilizer reference dimensions:

The horizontal stabilizer has three reference dimensions. These referencedimensions give horizontal stabilizer locations in inches. Measure each locationfrom buttock line 0. These are the horizontal stabilizer reference dimensions:

Stabilizer stationStabilizer leading edge stationElevator station

Measure stabilizer stations perpendicular to the horizontal stabilizer rear spar.

Measure stabilizer leading edge stations perpendicular to the horizontalstabilizer leading edge.

Measure elevator stations perpendicular to the elevator hinge centreline.

737- Horizontal stabilizer reference dimensions


ZONE DIAGRAM:

General:

The airplane has eight major zones to help you find and identify the airplanecomponents and parts. The major zones are divided into sub zones and the subzones into zones. These are the major zones:

100- Lower half of the fuselage200- Upper half of the fuselage300- Empennage400- Power plant and nacelle struts500- Left wing600- Right wing700- Landing gear and landing gear doors800- Doors

737- Zone diagram


General:

Two CFM56-7B engines supply thrust for the airplane. The engines also supplypower for these systems:

electric hydraulic pneumatic

737- Power plant


POWER PLANT ENGINE HAZARDS:It is dangerous to work around engines. Use the entry/exit corridor when theengine is in operation. Stay out of the inlet and exhaust areas when the engine isin operation.These are the hazards around an engine in operation:

Inlet suction-exhaust heat.Exhaust velocity-engine noise.

Inlet suction:

Engine inlet suction can pull people and large objects into the engine. At idlepower, the inlet hazard area is a 13 ft (4.0m) radius around the inlet.

Warning: If the wind is over 25 knots, increase the inlet hazard area by 20%.

Exhaust heat:

The engine exhaust is very hot for a long distance behind the engine. This cancause damage to personnel and equipment.

Exhaust velocity:

Exhaust velocity is very high for a long distance behind the engine. This cancause damage to personnel and equipment.

Engine noise:

Engine noise can cause temporary and permanent loss of your ability to hear.You must wear ear protection when near an engine in operation.

Engine entry/exit corridor:

Engine entry corridors are between the inlet hazard areas and the exhaust hazardareas. You should go near an engine in operation only when:

- the engine is at idle- you can speak with people in the flight compartment

For additional safety, wear a safety harness when the engine is in operation.


Training information point:

When the engine is in operation, the anti-collision lights should be on.

737- Power plant engine hazards


FLIGHT CONTROL SURFACES:

General:

The flight controls keep the airplane at the necessary altitude during flight. Theyhave movable surfaces on the wing and the empennage. These are the two typesof flight controls:

- primary- secondary

Primary flight controls:

The primary flight controls has these components:

Aileron (2)Elevator (2)Rudder

Secondary flight controls:

The secondary flight control system has these components:

Leading edge flaps (4), leading edge slats (8), trailing edge flaps (4),spoilers (12), horizontal stabilizer.

The 12 spoilers consist of 4 ground and 8 flight spoilers. The spoilers arenumbered 1 to 12, left to right.

Power source:

Hydraulic actuators or electric motors move the surfaces. You must be verycareful when you work near flight control surfaces. When hydraulic power is on,make sure that all the flight control surfaces are clear of personnel andequipment.


737- Flight control surfaces


DOORS introduction

Purpose

The doors are movable units that give access to the airplane compartments.

General description:

These are the types of doors on the airplane:- forward and aft entry doors- forward and aft galley service doors- emergency exit hatches (and pilots’ sliding windows)- cargo doors- interior doors (crew door and lavatory doors)- miscellaneous access doors

Location:

The entry doors are on the left side of the airplane.The galley service doors on the right side of the airplane.The emergency exit hatches are above the wings on both sides of the airplane.The pilot’s sliding windows are in the flight compartment.The crew door and lavatory doors are inside the airplane.The cargo doors are on the right side of the airplane.The miscellaneous access doors are near the systems they serve.

Training information point:

You can open and close entry, galley service, and cargo doors in winds up to 40knots without structural damage. You can let these doors stay latched open inwinds up to 65 knots without structural damage.If a door is left open for a long time, a protective cover should be put over thedoor frame. This prevents bad weather damage to the airplane.


737- Doors


FLIGHT COMPARTMENT PANELS:

Flight Compartment panels:

These are the major panels in the flight compartment:- P1 captain instrument panel- P2 centre instrument panel- P5 forward overhead panel- P5 aft overhead panel- P7 glare shield panel- P3 first officer instrument panel- P9 forward electronic panel- control stand- P8 aft electronic panel

737- Flight compartment panels


LEVELING AND WEIGHING – DESCRIPTION AND OPERATION:

General:

Refer to figure 14.

A. The aircraft is made level to do the weighing procedures and to do somemaintenance procedures.

B. The weighing procedures are done to find the total weight and centre ofgravity of the aircraft. The weight is measured with the aircraft on jacks.To find the total weight and centre of gravity, the weights measured ateach jacking are added.

Levelling and weighing of the aircraftFig 14


TOWING AND TAXIING – DESCRIPTION AND OPERATION:

1- General:

A. TowingThe aircraft can be towed or pushed with a towing tractor when it is impracticalto move the aircraft whit its own power. The aircraft is towed with a tow bar thatattaches to the axle of the nose landing gear. A minimum of two persons isnecessary for towing operations. Five persons are necessary for towingoperations in confined areas.

B. Taxiing:Taxiing operations are done with an operator in the pilot’s seat. The operatormoves the aircraft with the combined use of the engine power, the brakes andthe nose wheel steering.

2- Description:

A. Towing:Refer to figure 15.

(1)The aircraft is pushed or towed with the tow bar connected to the axle ofthe nose landing gear and to the towing tractor. The nose-wheel steeringsystem must be off and the steering torque arms disconnected when theaircraft is towed or pushed to permit the nose wheel to turn freely. Withthe steering torque arms disconnected, the nose wheel can be turned 360degrees.

(2)The towing radii shown in figure 15 is based on towing operations withthe nose wheel turned 90 degrees from the centre to get the smallestpossible turning circle.

B. Taxiing:

(1)For taxiing operations, the use of engine thrust is necessary. Control of theaircraft is with the brakes and the nose wheel steering. With the nose-wheel steering system on, the nose-wheel steering range is 70 degrees leftor right.

(2)The aircraft can be controlled with the nose-wheel steering system off byuse of differential thrust and brakes. With the nose-wheel steering systemoff, the nose wheel can turn freely 70 degrees left and right during ataxiing operation.


WARNING: When you tow the airplane, all persons must stay out of thedangerous areas around the tow vehicle, tow bar and nose wheels. Personnel onthe ground must be aware of the possibility of being run over by the nosewheels. The tow vehicle, tow bar, and airplane will change position duringpushback and towing. Maintain a minimum of 10 feet separation betweenpersons on the ground and the equipment that moves. A fatal injury could occur.

Towing of the aircraftFigure 15


JACKING POINTS:

General:

These are seven jacking points to lift and stabilize the airplane. The jackingpoints consist of three main and four auxiliary jack points.

The main jack points are the wing jack points A and B, and the aft body jackpoint C. These jack points allow you to connect jacks and lift the completeairplane.

The four auxiliary jack points are the forward body jack point, the nose gearaxle jack point, and the two main gear axle jack points. The forward body jackpoint at position D stabilizes the airplane. Jack points E and F, underneath thelanding gear axles, lets you remove the wheel and tire or brake assembly withoutjacking the complete airplane.

Before you jack the airplane, make sure that the airplane gross weight and thecentre of gravity are within the approved limits.


737-jacking points


PARKING AND MOORING-DESCRIPTION AND OPERATION:

1. General:

A. Parking and mooring of the aircraft must be done properly to prevent damageto the aircraft and to prevent injuries to persons when the aircraft is parked. Theweather conditions and the length of time the aircraft is parked are used to findthe level of precautions necessary. If possible, park the aircraft in a hangar, butif this is not possible, park the aircraft into the wind.


SERVICING

1. General:

A. ground hydraulic power servicingB. external AC powerC. external DC powerD. ground air servicingE. fuel system replenishingF. hydraulic system replenishingG. oil system replenishingH. oxygen system replenishingI. water/waste replenishing

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