Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Cat B- Mod 11 Aircraft Systems > 11.2.a Structures General > Flashcards

11.2.a Structures General Flashcards

1
Q

What philosophy are modern structures developed with?

A

Stressed skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is PSE?

A

Principle Structural Elements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are Principle Structural Elements?

A

The part of the aircraft that contributes significantly to carrying flight, ground, or cabin pressure loads.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are some of the PSE’s?

A

Wings
Horizontal Stab
Vertical Stab
Canard
Forward wing
Winglets
Pressurised areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How are aircraft strength requirements specified?

A

In terms of the max loads expected in service and max load plus safety factor.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a flight load?

A

The maximum loads expected in service.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is an ultimate limit load?

A

Flight limit loads multiplied by a factor of safety.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where is the criteria found for limit loads of large aircraft?

A

CS-25

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the five forces acting on an aircraft?

A

Torsion
Tension
Shear
Bending
Compression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is torsion?

A

Stretch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is compression?

A

Squeeze

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is torsion?

A

Twist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is shear?

A

One layer moving opposite to the other.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is bending?

A

Combination of tension and compression.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the three categories of structure?

A

Primary
Secondary
Tertiary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is primary structure?

A

Any part that should it fail lead to loss of control or catastrophic failures and harm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are some examples of primary structure?

A

Wing spars
Engine Mounts
Fuselage frames

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is an SSI?

A

Structurally significant item.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is secondary structure?

A

Non-primary structural components such as ribs, stringers and segments of skin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is secondary structure less prone too?

A

Weakening without facing failure risks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is tertiary structure?

A

Remaining components of the aircrafts framework.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What kind of stuff comes under tertiary structure?

A

Fairings
Fillets
Support brackets

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What does the document FAA AC 23-13A evaluate?

A

Fail safe load transfer
Damage tolerance
Fatigue indexing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a fail safe design?

A

Duplication of structural methods to ensure if one fails then the other will take the load.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the disadvantage of fail safe designs?
They add weight.
26
What is the modern version of fail safe?
Damage tolerance.
27
What is safe life concept?
Prediction of how long a structure can remain in service.
28
How is the safe life indicated?
As a number of cycles or hours.
29
What is the safe life given to the structure?
1/3 of the max calculated hours.
30
What does the damage tolerance concept require?
Evaluation of the structure.
31
What does damage tolerance testing look like?
Repeated static and dynamic load tests, which demonstrate that the structure can withstand the loads expected in service plus a factor of safety.
32
What is another type of damage tolerant structure?
Multiple load path concept.
33
How does multiple load path concept work?
Large, heavy, and highly stressed members are avoided. Small members carry the loads, each supporting only a small percentage of the total.
34
What are crack limiting joints?
Specially designed structure that will limit the spread of cracks but ensure they can be detected.
35
What are the five main structural units?
Fuselage Wings Stabilisers Flight Control surfaces Landing Gears
36
How are the primary dimensions of an aircraft calculated?
There are defined zones, reference points, lines and planes.
37
What are the reference planes?
Vertical Horizontal Longitudinal
38
What are the 8 major zones of an aircraft?
100-800
39
What is zone 100?
Lower fuse
40
What is zone 200?
Upper fuse
41
What is zone 300?
Empennage
42
What is zone 400?
Power plant
43
What is zone 500?
Left wing
44
What is zone 600?
Right Wing
45
What is zone 700?
Landing gear
46
What is zone 800?
Doors
47
The second digit of the zone code is what range for small aircraft or large aircraft?
1-6 for small 1-9 for large
48
On a fuselage how are the coordinates identified?
By body, fuselage stations or water lines and butt lines.
49
What is meant by BS or FS?
Body station or Fuse station
50
How is the body station measured?
From a datum in front of the nose.
51
What are the butt lines?
Vertical planes parallel to the body centreline plane.
52
What is the body butt line 0?
Centreline
53
What are body waterlines?
The horizontal planes at right angles to the butt lines.
54
Where are wing stations measured from?
Either a butt line reference point or from wing rib 1.
55
What are component stations used for?
Various components such as flying controls.
56
What is tension measured in?
Newtons in ISU or Pounds force in imperial
57
How do you calculate tensile strength?
Load of material divided by cross sectional area
58
What is shear strength usually equal to or less than?
Tensile or compressive strength.
59
How is stress created?
When a material is subject to force.
60
What is bending stress a combination of?
Compression and tension
61
What is hoop stress?
The pressure on a cylinder outwards from the centre on the circumference.
62
For any given pressure, what will the hoop stress be?
Twice the value of the longitudinal stress.
63
What is strain a ratio of?
Deformation of a material caused by stress.
64
How is strain calculated?
Change in length divided by the original length.
65
What is fatigue?
Cyclic or alternate loads.
66
What is effective drainage and ventilation crucial for?
Preventing fluids becoming trapped.
67
How do fluids get to the drain holes?
System of longitudinal and cross drain paths.
68
How is loss of pressure prevented from drain holes?
Bilge like valves are used.
69
What must be ventilated to permit vapour to evaporate?
Any cavity in structure that may have flammable vapour or water.
70
Where are ventilation requirements found?
CS-25
71
How is the fittings, attachments and space decided for instruments?
Type Cost Usage Serviceability
72
How must LRU's be placed?
Quickly fitted and removed.
73
How is an aircraft protected from lightning strike?
Bonding Earths External skin
74
If an aircraft is hit by lightning it is important too...?
General walk around Find signs of damage
75
What two types of damage do you get from lightning strikes?
Direct Indirect
76
What is direct damage?
Surface is burnt, melted, or show signs of metallic distortion.
77
What is indirect damage?
Damage to the electrical system and equipment that was caused by large transients on the wiring.
78
If a lightning strike has caused a system malfunction what is there a requirement for?
Full inspection of the defective system.
79
What does a lightning strike normally look like?
Small circular melt or scorch marks approx 3mm in diameter.
80
What other things are inspected in a lightning inspection?
Fuel system valves IDG Hyd fittings Radio Nav
81
What is bonding?
Joining two electrical conductors together.
82
What is grounding?
Process of electrically connecting conductive objects to structure or return path.
83
What is the aim of boding?
Preventing build up of static charges and minimising the risk of electrical arcing and interference with on-board electronic systems.
84
How is hardware used for bonding selected?
Mechanical strength Current Ease of installation
85
When installing grounds what conditions apply?
Must be separated (AC/DC/shields) No more than 4 on one stud Dual grounds must be installed in fuel vapour areas
86
How is composite structure bonded?
They have an aluminium mesh in the layers.
87
What is composite direct bonding?
Exposing the mesh and mounting equipment directly onto it.
88
What is indirect composite bonding?
Exposing the mesh and installing a wire or connector.
89
When testing a bond lead contact point what max ohms must be seen?
0.025
90

Cat B- Mod 11 Aircraft Systems (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions