11.3.1 - Fuselage Structures

Question 1

What are production break points?

Answer 1

Production break points are where the fuselage is broken up into sections and riveted together during manufacture.

Question 2

How is the cabin floor supported?

Answer 2

Support struts and crossbeams support the cabin floor structure.

Question 3

What is a ‘‘Plug Door’’?

Answer 3

Plug-type doors are a little bigger than the dimensions of the door jamb in which they fit

Question 4

What takes the pressure loads during flight on a door?

Answer 4

The total load is distributed over the whole door jamb

Question 5

Where would you find a non-plug type door?

Answer 5

Cargo compartment doors

Question 6

What are the advantages and disadvantages of the outward opening cargo door?

Answer 6

Advantage - More cargo space compared to inward opening door

Disadvantage - mechanics more complex and stronger requirements as pressure inside will try to force door outwards

Question 7

How are the flight crew alerted to an open door condition on the aircraft?

Answer 7

Proximity sensors on the doors

Green/red lights on cockpit screen

Question 8

What are the layers made from in a main cockpit window?

Answer 8

Cockpit windows consist of layers of toughened glass and plastics

Question 9

What material are the window heating elements made of?

Answer 9

Gold, tin oxide & indium oxide

Question 10

Why heat cockpit windows?

Answer 10

• Increase the flexibility of the windshields (Bird strike)
• Keeps the windows free of ice
• Keeps the windows from fogging over

Question 11

What type of damage would you inspect a cockpit window for?

Answer 11

• Delamination (layers coming loose)
  Pealing
• Tearing
• Breaking

Question 12

What material are cabin windows made from and why?

Answer 12

Certain synthetic (acryllic) windows

They have a larger coefficient of expansion than the surrounding surface.

Question 13

What is the purpose of the inner pane on a cabin window and which window takes the load?

Answer 13

Inner pane is designed as backup if window doubler fails (fail-safe design)
Also vent hole in the inner pane to allow for pressure adjustment

The window doubler takes the load

Question 14

What kind of stressed skin structure is used for the construction of
pressurised fuselages?

Answer 14

Semi-monocoque is used in modern commercial aviation

Question 15

Which zones of the fuselage are usually pressurised?

Answer 15

The cockpit, cabin, avionics compartment and cargo compartment are normally pressurised

Question 16

____ Skin type fuselages are used in modern transport aircraft

Most fuselages of transport aircraft are ____ _____ structures. It is shaped by a number of frames and ______ to keep each other at the correct distance

Answer 16

Stressed

Semi-monocoque

stringers

Question 17

_____ ____ and ______ support the cabin floor structure

Answer 17

Support struts

crossbeams

Question 18

Plug-type doors are a little _____ than the dimensions of the ____ ____ in which they fit

Answer 18

bigger

door jamb

Question 19

For cockpit windows, there is a heating element between the _____ window and the ____ layer

Answer 19

outside

plastic

Question 20

The heating element is made of …

Answer 20

Gold, tin oxide or indium oxide

Question 21

Heating the cockpit windshields is necessary because:

Answer 21

• It increases the flexibility of the windshield (birds)
• It keeps the windows free of ice
• It keeps the windows from fogging over

Question 22

There is a small ______ _____ in the inside window to allow for adjustment for ______ differences between the inside and outside window

Answer 22

ventilation hole

pressure