Systems 2

1% added mass minuses…

5% cruise time

Wing bending at the tips increase ____ due to a higher AoA

Drag

Why are the engines forward of the wing

To bring the centre of gravity of the wing forward to reduce flutter

What is wing flutter

Where the wing goes in a cycle of bending up and down while changing AoA due to the CoG changing positions

Flexural Aileron Flutter

Where the aileron changes position due to change in CoG, To fix this, the center of gravity should be closest to the main wing

Mass balancing

Reduces wing and aileron flutter by changing the CoG so flutter wont occur

Honeycomb structure

Two load-bearing skins separated by a lightweight material in a honeycomb pattern for extra strength

A metal used commonly in aircraft

Steel, titanium, or aluminium alloys (Duralumin)

Steel is

a mixture of iron, carbon and other elements

Duralumin Is

Aluminium Alloy with copper and magnesium, which has a high stregnth to weight ratio

Magnesium

Excellent strength to weight ratio, burns fiercely

Composite Materials

Made of two or more materials with different properties, strong fibres held in a plastic protective matrix

Composite material failure

Shock, impact or repeated process’ can separate the layers (delamination)

Glass reinforced Plastic

Material mainly used on radome on many aircraft

Kevlar

A type of carbon fibre, 5 times stronger than steel

Composite advantage

Very strong, light weight, and mouldable before baking

Composite disadvantage

Expensive, hard to inspect, impossible to repair

Metal corrosion

Deterioration of metal. Salt based environments are more corrosive

Avoiding metal corrosion

Painting, inspection, washing

Stress corrosion

Combination of stress and corrosion

High risk areas for corrosion

Corrosive environments - near the ocean with salty sea

Aircraft life determinations

Safe life, fail safe and damage tolerant

Safe life

A aircraft is taken out of service significantly before the calculated fatigue failure life, based on declared number of cycles or time period

Fail safe

a component when part of it fails, the whole structure remains in tact by having multiple load paths

Damage tolerant

Ability to withstand damage without catastrophic failure by having multiple load paths

On condition maintenance

Replace as necessary

Hard time Maintenance

Replacing a component when its time life or amount of cycles is over

Plug Doors

Opens inwards and fits in a socket creating cabin pressure

Non plug door

Opens outwards, used for passenger doors

Hinge doors

Opens outwards and must be locked for flight

Cargo doors

Opens outwards and must be pressurised