S Aircraft Construction Flashcards
3 main aircraft sub assemblies
Fuselage
Wings
Empennage
5 attachment methods?
- Riveting
- Welding
- Bolting
- Pinning
- Adhesives
What is the name of a joint which connects 2 panels together using rivets?
Doubler joint
What is a method of ensuring bolts do not come loose?
Wire locking
Can composite materials be riveted?
No
How do we attach composite materials?
Composite fastener
What isa longeron?
Main longitudinal load bearing member of the fuselage
What are stringers?
Run longitudinally, bonded to the skin, help withstand buckling
What are formers/frames?
Define the shape and provide skin attachment points
What doos the aircraft skin do?
Provides aerodynamic shape as well as withstanding tension and compression stresses
What is a bulkhead?
Provide structural partitions inside the fuselage and give structural support
What is a firewall?
Fire resistant bulkhead installed between engine compartment and the rest of the airframe structure
What are intercostels?
When weaker areas around the windows and doors are reinforced with frames and stringers
What is a machined structure?
A single piece of material effectively carved with components included in its shape, removing the need for joints
Why are most fuselage sections circular?
Eliminating corners helps ensure laminar flow
Circular cross section can more easily withstand loads imposed by pressurisation
What is a double bubble structure?
Intersecting circles tied together by the fuselage floor
What shape are unpressurised aircraft?
Don’t have to be circular, can vary more widely
3 advantages of an oval fuselage?
- Lower manufacturing cost
- Greater capacity
- Better options for cargo
Where is the pressure hull located?
Between the forward and rear pressure bulkheads
What is the pressure bulkhead pressurised to?
Between 8 and 9psi
What is axial stress?
Stress acting along the longitudinal axis
What is hoop stress?
Stress that acts radially across the fuselage structure
When do axial and hoop stresses occur?
Cyclic stresses - every time the cabin is pressurised
What are 3 types of wing design?
Cantilever
Semi-cantilever
Externally braced