References:

[a] Boeing C_40A Aircraft Maintenance Manuals, Part 1, System Description Section
[b] C-40A Operations Manual, Vol. 2

201.1 SYSTEM COMPONENTS AND COMPONENT PARTS

Referring to a standard print of this system or the actual equipment, identify the following system components and component parts and discuss the designated items for each: [ref. a]

A. What is its function?
B. Where is it located?

201.1.1 Aircraft structure:

Fuselage

Function and Location:

The fuselage is 105 foot 7 inch long, 158 inch high cylindrical shaped compartment, which provides pressurized and non-pressurized compartment(s) containing avionics, mechanical, and safety devices for aircrew, personnel and cargo, to which the wings, elevators, and rudder are attached.

Stabilizers

Function and Location:

Horizontal stabilizer spans 47 feet 1 inch and it effects sweep and affects pitch control and reduces uncontrolled movement along the lateral axis.

Vertical stabilizer rises 41 feet 3 inches from the ground, and affects yaw control along the vertical axis.

Wings

Function and Location:

The wings span 112 feet 7 inches. They provide lift and attachment points for flight control surfaces (ie: ailerons) and engines.

Engine pylons

Function and Location:

Two pylons, one on each wing, are attached to the wings 15 feet 10 inches from aircraft centerline. They are the attachment structures connecting the engines to the wings and provide aerodynamic properties and protection of engine related components.

Radome

Function and Location:

The aerodynamic cone on the forward end of the fuselage covers the radar dish and additional avionics. The radome provides aerodynamic properties and protection of electronics and radar components.

Doors

Function and Location:

There are six doors/hatches used for normal maintenance and egress purposes (forward passenger, forward galley service, over wing (2), aft passenger, aft galley service) and five main access doors/hatches (Forward cargo, aft cargo, APU access, forward access, E/E bay) then the main deck cargo door.

Air stairs

Function and Location:

Located in the E/E compartment and operated from either the flight deck or from the exterior forward passenger door.

201.1.2 Flight controls:

Control column

Function and Location:

Located in the flight compartment, there are two control columns (pilot/first officer) and are used (push/pull) to control the elevators.

Rudder pedals

Function and Location:

Located in the flight compartment, there are two pairs of pedals (pilot/first officer) on the floor, forward of the control column and are used for steering (up to 7 degrees each side of center) and yaw control.

Ailerons

Function and Location:

Located on the trailing edge of the outer wings, with input from the control wheel on the control column, operate ailerons and flight spoilers inducing changes in the aerodynamics causing the aircraft to roll along the longitudinal axis.

Rudder

Function and Location:

Located on the trailing edge of the vertical stabilizer, with input from the control column, induces changes in the aerodynamics causing the aircraft to yaw along the vertical axis.

Elevators

Function and Location:

Located on the trailing edges of the horizontal stabilizer, with input from the rudder pedals, induce changes in the aerodynamics causing the aircraft to pitch along the lateral axis.

Trim tab

Function and Location:

Small airfoils located on the trailing edges of the ailerons, elevators, and rudder, with input from trim tab controls in the flight cabin, causes minute changes in the desired direction.

Flaps

Function and Location:

The leading edge flaps, located inboard of the engines, and trailing edge flaps on the trailing edges of the mid- and inner wings, are high lift devices that increase wing lift and decrease stall speed during takeoff, low speed maneuvering and landing.

Slats

Function and Location:

The leading edge slats, located outboard of the engines, are high lift devices that increase wing lift and decrease stall speed during takeoff, low speed maneuvering and landing.

Flight spoilers

Function and Location:

Four flight spoilers are located on the upper surface of each wing. These are used as speed brakes to increase drag and reduce lift, both in flight and on the ground. The flight spoilers also supplement roll control in response to control wheel commands.

Ground spoilers

Function:

Works with the flight spoilers as speed brakes when the aircraft is on the ground to increase drag and decrease speed.

Krueger flaps

Function and Location:

A flap control system with the airfoil surfaces located on the lower side of the leading edge of the inner wings. They are high lift devices that increase wing lift and decrease stall speed during takeoff, low speed maneuvering and landing.

201.1.3 Hydraulics:

Pumps

Function and Location:

Both A and B hydraulic systems have an engine-driven pump and an AC electric motor-driven pump. An engine-driven hydraulic pump supplies approximately 4 times the fluid volume of the related electric motor-driven hydraulic pump.

Reservoirs

Location:

Each hydraulic system (System A, B and Standby) reservoir located in the main wheel well area.

Power Transfer Unit (PTU)

Function and Location:

Supplies additional volume of hydraulic fluid needed to operate the auto-slats and leading edge flaps and slats at the normal rate when system B engine-driven hydraulic pump volume is lost.

State the purpose of the hydraulic system

Function and Location:

Either A or B hydraulic system can power all flight controls with no decrease in airplane controllability.

201.1.4 Landing gear:

Struts

Function and Location:

The two main landing gear (MLG) absorbs landing forces and holds most of the airplane weight when the airplane is on the ground. The main landing gear also transmits the braking forces to the airplane structure.
The airplane has two main landing gears and a single nose gear. Each main gear is a conventional two-wheel landing gear unit. The nose gear is a conventional steerable two-wheel unit. Hydraulic power for retraction, extension, and nose wheel steering is normally supplied by hydraulic system A.

Brakes

Function and Location:

Each min gear wheel has a multi-disk hydraulic powered brake. The brake pedals provide independent control of the left and right brakes.

Wheels

Function and Location:

The main landing gear wheels are made of inner and outer wheel halves. Tie bolts hold the two halves together.

Nose doors

Function and Location:

The nose landing gear doors open to permit gear operation. They close to aerodynamically seal the nose landing gear well to decrease drag. They are attached to the outboard edges of the nose landing gear wheel well with hinges.

Nosewheel steering

Function and Location:

The nose wheel steering system supplies the ground directional control of the airplane. Steering inputs come from the steering wheel or the rudder pedals.

Proximity Switch Electronics Unit (PSEU)

Function and Location:

Hydraulic system A usually supplies pressure to the landing gear extension and retraction. Hydraulic system B supplies pressure for retraction only through the landing gear transfer valve. The landing gear transfer valve receives electrical signals from the proximity switch electronics unit (PSEU).

Antiskid/autobrake

Function and Location:

The antiskid system controls the brake system to prevent wheel skids during brake application.

201.1.5 Fuel:

Tanks

Function and Location:

There are three tanks:

Main tank 1 is in the wing box of the left wing. Main tank 2 is in the wing box of the right wing. The center tank is in the fuselage and the left and right wing root. The capacity of the main tanks 8,630 lbs each. The capacity of the center tank is 28,830 lbs. Fuel tank capacity does not include surge tanks. The capacity of each surge tank is 235 lbs.

Vents

Function and Location:

The fuel vent system keeps the pressure of the fuel tanks near the ambient pressure.

Boost pumps

Function and Location:

There are two center tank boost pumps on the center tank. They are on the rear spar. Access to the center tank boost pumps is through the wheel wells.

There are forward and aft boost pumps in the main tank No. 1 and No. 2. The forward boost pumps are on the front spar. The aft boost pumps are on the rear spar. Access to the forward boost pumps is through extended Krueger flaps. Access to the aft boost pumps is through the wheel wells.

The APU dc boost pump supplies fuel to the APU. The APU dc boost pump has a pump assembly and a housing assembly. The housing assembly is inside the fuel tank. The pump assembly attaches to the outside of the fuel tank. The APU dc boost pump is on the left wing rear spar.

Control panels

Function and Location:

The pressure fueling system lets you refuel all tanks. You also use the system during fuel transfer from tank to tank. The fueling station permits automatic and manual control of the fueling shutoff valves.

201.2 PRINCIPLES OF OPERATION

201.2.1 What is the sequence of component involvement to accomplish movement of flight surfaces?

Function and Location:

Control wheels move cables that give input to feel and centering units, which in turn control proximity control units (PCU). The PCU(s) move cables or torque tubes to move the flight surfaces.

201.3 PARAMETERS/OPERATING LIMITS

For the items listed, answer the following questions: [ref. a]

A. What are the allowable operating limits?

201.3.1 Main cargo door Function and Location:

You can operate or let the main deck cargo door stay open at or above the canopy position in winds below 40 knots without structural damage. If it is raining, do not operate the main deck cargo door above the canopy position. If you let water into the passenger service units and its oxygen generators, damage to the equipment can occur.

201.3.2 Entrance/service doors

Function:

You can open and close entry, galley service, and cargo doors in winds up to 40 knots without structural damage. You can let these doors stay latched open in winds up to 65 knots without structural damage.

201.4 SYSTEM INTERFACE � None to be discussed.

201.5 SAFETY PRECAUTIONS

201.5.1 What special safety precautions apply to: [ref. a]

Extending Krueger flaps and slats

Make sure the inboard fan duct cowl and teh thrust reversers are closed or removed before you extend the OR REMOVED BEFORE YOU EXTEND THE LE FLAPS AND SLATS. THERE IS NOT SUFFICIENT CLEARANCE FOR THE LE FLAPS AND SLATS TO EXTEND IF THE INBOARD FAN DUCT COWL AND THE THRUST REVERSERS ARE IN THE OPEN (MAINTENANCE) POSITION. THIS CAN CAUSE DAMAGE TO EQUIPMENT.

Opening over wing exit and doors

If you open the door from the outside of the airplane, brace your knee against the door to prevent injury.

Pressurized hydraulic components

Keep persons and equipment away from all control surfaces and the nose grea when hydraulic power is applied. The ailerons, elevators, rudder, flaps, slats, spoilers, and nose gear are supplied with power by the hydraulic systems. Injuries to persons or damage to equipment can occur when hydraulic power is supplied.

You must monitor the instruments and indicator lights for the hydraulic systems when hydraulic systems are pressurized. This is to make sure the hydraulic systems operate correctly. If the overheat light of a hydraulic system comes on, you must stop the operation of that hydraulic system immediately. Damage to the equipment can occur if you do not do this.

Do not operate the EMDP for more than 2 minutes if the No. 1 Fuel Tank contains less than 250 gallons (1675 lbs/760 Kilograms) of fuel. You must let the reservoir temperature decrease to ambient temperature before you operate the pump again. Damage to equipment can occur if you do not do this.

BMS 3-11 type 4 fire resistant hydraulic fluid (Skydrol)

Hydraulic Fluid, BMS 3-11 Type IV (Skydrol), can cause injury to persons. If you get the hydraulic fluid in your eyes, flush the eyes with water and get medical aid. If you eat or drink the fluid, get medical attention.