ATA 51 - Standard Practices/Structures

Question 1

What are the four typical principles used in aircraft design?

Answer 1

• Fuselage - skin is attached to the frames and stiffened by stringers
• Boxes - Skins stiffened with stiffeners are attached to spars and ribs
• Composite parts could be monolithic or sandwich construction

Question 2

In terms of ATA chapters how is the structure of the aircraft broken down?

Answer 2

• ATA 52 - doors
• ATA 53 - fuselage
• ATA 54 - pylons
• ATA 55 - stabilisers
• ATA 56 - windows
• ATA 57 - wings

Question 3

In terms of structure, what do the passenger/crew doors and the emergency exit doors comprise?

Answer 3

Same aluminium alloy design comprising skins, edge members, horizontal beams and vertical frames

Question 4

What do the forward and aft cargo door consist of?

Answer 4

Aluminium alloy structures consisting of skins, edge members, corner pieces, horizontal beams and vertical frames

Question 5

Describe the bulk cargo door?

Answer 5

Plug type design opening inside the fuselage

Comprise skins, edge members and horizontal beams both being made from aluminium alloy

Question 6

Describe the main landing gear doors?

Answer 6

Composite construction, including carbon fibre skins

Question 7

How many parts is the fuselage divided into in the technical documentation?

Answer 7

Five

Question 8

How does the fuselage structure compare between A321 and A320?

Answer 8

8 frames added FWD of the centre section and 5 frames added AFT of the centre section

Question 9

How does the fuselage structure compare between A319 to the A320?

Answer 9

3 frames removed FWD of the centre section and 4 frames removed AFT of the centre section

Question 10

How does the fuselage structure compare between the A319 to the A318?

Answer 10

1.5 frames removed FWD of the centre section and 3 frames removed AFT of the centre section

Question 11

Describe the primary structure of the pylon?

Answer 11

The pylon box which is an assembly of titanium alloy and steel parts

Includes spars, ribs, side panels, engine attachment and pylon to wing attachment fittings

Question 12

Describe the secondary structure of the pylon?

Answer 12

Comprises forward, lower and the aft fairings, and the pylon to wing centre fillets

Question 13

What does the horizontal stabiliser include?

Answer 13

Centre joint and two outer spar boxes

Question 14

What is the leading edge and trailing edge structure of the horizontal stabiliser made from?

Answer 14

Mainly from Carbon Fibre Reinforced Plastic (CFRP)

Question 15

What is the tip of the horizontal stabiliser made from?

Answer 15

Aluminium alloy

Question 16

What are the elevators made of?

Answer 16

CFRP structure including top and bottom skin panels, ribs and front spar

Hinge and actuator fittings and the trailing edge profile are made from aluminium alloy

Question 17

What does the structure of the vertical stabiliser consist of?

Answer 17

• Main spar box
• Leading edge
• Tip
• Trailing edge

Question 18

Describe the main box of the vertical stabiliser?

Answer 18

Assembly of CFRP ribs, spars and side panels

Question 19

Describe the vertical stabiliser structure?

Answer 19

• Leading edge made of GFRP
• Tip made of GFRP
• Trailing edge structure made of aluminium alloy
• Trailing edge panels made of CFRP

Question 20

Describe the structure of the rudder?

Answer 20

• Two side panels made of CFRP
• Front spar made of CFRP
• Leading edge panels made of CFRP
• Hinge and actuator fittings made of aluminium alloy
• Trailing edge profile made of aluminium alloy

Question 21

Which components are included in the cockpit windows?

Answer 21

• Windshield
• Sliding windows
• Side fixed windows

Question 22

How are the cabin windows held in position?

Answer 22

By a retainer ring

Question 23

What does the wing centre box provide?

Answer 23

Cantilever attachment for the outer wings

Question 24

Describe the wing centre box?

Answer 24

Assembly of aluminium alloy parts

Located between frames 36 to 42

Question 25

What is the purpose of the main box of the outer wing?

Answer 25

Main load carrying structure Supports a fixed leading edge structure, fixed trailing edge structure and a wing tip

Question 26

Describe the leading edge structure?

Answer 26

Has leading edge ribs, attached to the main box front spar, and which supports the “D-nose” structure

Question 27

What does the fixed trailing edge of the outer wings include?

Answer 27

Hinge fittings and actuator fittings for the movable surfaces and intermediate ribs

Question 28

What are the access panels of the outer wing made of?

Answer 28

CFRP

Question 29

What movable surfaces is each outer wing fitted with?

Answer 29

* Five slats * An inboard and outboard flap * Five spoilers * One aileron

Question 30

What are the slats made of?

Answer 30

Aluminium alloy

Question 31

What are the flaps made of?

Answer 31

CFRP structure and a sandwich aluminium trailing edge structure

Question 32

What are the spoilers and ailerons made of?

Answer 32

CFRP

Question 33

What is the nose cone made of?

Answer 33

Quartz Fibre Reinforced Plastic