Chapter 4 Structure Concepts

Question 1

parts carrying almost no loading

Answer 1

frames, ribs, leading and trailing edge

Question 2

structure concept

Answer 2

1. load paths
2. position of load carrying elements
3. interfaces between different components
4. material selection
5. constructive details related to the manufacturing technology

Question 3

net load on an aircraft

Answer 3

net load = aerodynamics - inertia

Question 4

stick model

Answer 4

simplifying a structure as beams

Question 5

load paths

Answer 5

wing supports fuselage, and fuselage supports wing

VTP is supported by fuselage

HTP is supported by VTP

Question 6

bending stresses are painful because …

Answer 6

… material load bearing capacity is not exploited, hence more material is needed

Question 7

sandwich

Answer 7

alternative to stringer-stiffened panel

two thin load carrying skins (carbon composites, aluminum) bonded to a light-weight core (aramid, fiberglass, aluminum)

+ high bending stiffness (high critical buckling stress)
+ good damping
- consume a lot of volume
- difficult to join (because of weak core)
- capture moisture

Question 8

load-carrying part of a wing

Answer 8

wingbox

consists of skin, stringers, spars, ribs

Question 9

fuselage consists of …

Answer 9

… skin, stringers, frames, longerons, floors

Question 10

major structure interfaces

Answer 10

1. wing - fuselage
2. empennage - fuselage
3. engine - wing / fuselage
4. landing gear - wing / fuselage
5. etc.