Section A: Flashcards
Aircraft Structure must be?
Lightweight, Strong, Durable, Stiff
What are the limit, proof and ultimate load?
maximum faced, load handled without yield, load handled without catastrophic failure.
Wing Structural requirements?
Aerodynamic, Stiffness, Strength, Subsystem, Durability
Spar Function?
To carry the vertical shear force and direct bending stresses. Forms the front and rear of the wing box.
Rib Function?
Maintains the shape of the wing. Transfers load from the stringers to the spars. Support for stringers. Carries shear force for stringers, bending moments, in-plane tension and compression.
Wing Skin and Stringer Function?
Carries Stresses from aerodynamic loads. Provides smooth profile. Carry stresses during torsion.
Prevents wrinkling of skin. Transfers load to spars. Supports skin. Can be used to join skin pieces.
Fuselage Components?
Skin, Frames, Stringers, Longerons, Bulkhead
Types of Cyclic Fatigue?
Cabin Pressure, GAG, Landing, Maneuvers and Gusts, Flaps and Control Surfaces.
What is the Fail Safe Philosophy?
Parts need to be damage tolerant, easily checked for damage and be easily replaceable.
What is E(u)?
Nunber of gust cycles per km with speed greater than u
What is Strip Theory?
Lift is proportional to incidence angle, uniform lift co-efficient, local lift force acts through the A.C.
What is the Effective Lift Moment Arm?
Root Bending Moment / Total Lift
What are the methods of increasing the Divergence Speed?
Increasing torsional stiffness, sweeping the wing backwards, decreasing e.
What are the Reversal Model assumptions?
We assume that both forces have identical distributions, and that the centre of lift for both effects is constant.
What are the methods of increasing the Reversal Speed?
Decreasing d, increasing torsional stiffness, placing aileron further inboard.
