Aircraft general knowledge
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nurse001
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THE
PILOT
Aircraft
general
knowledge
ATPL
STUDENT
pilot
resume
all info you need to pass atpl exams
Downloaded by: nurse001 |
Distribution of this document is illegal
, Stuvia.com - The Marketplace to Buy and Sell your Study Material
AGK
System design, load, stress & maintenance
• Damage/fault tolerant design:
- Capability to withstand a certain amount of weakening of a structure without catastrophic failure
- Takes cracking of the structure into account
• Fail safe design:
- More than one load carrying component, parallel structural parts, load sharing
- Based on redundancy of components
- Does not imply that the system will never fail despite having backups
• Safe life design:
- Replacement of part after a given number of cycles/flight hours in use
- One load carrying component is sufficient provided it is strong enough
- Does not imply that the system will never fail in the safe life period
There is no most favourable design method, as each component varies
• Maintenance:
1. Hard time: Component overhauled/removed after a set number of hours/cycles regardless of condition
2. On condition: Monitoring of critical parameters & replacement of parts if a limit value is exceeded
• Stress: Force/area
1. Tension: Force resisting from being pulled apart
2. Torsion: Caused by twisting
3. Compression: Push force
4. Torque: Axial rotation force
5. Shear: Force parallel to cross section
6. Buckling: Effect of more than one force
• Strain:
- Deformation due to stress, expressed as a % change of dimension of original dimension
• Elastic deformation
- Tendency of material to return to its original state
- Temporary & reverses when load is removed
• Corrosion: Incorrect metallic bonding
1. Stress: Continuous tensile load + corrosion
2. Intergranular: Grain boundaries inside metal
• Fatigue: Material is continually loaded & unloaded & will eventually break even though load is the same
• Aircraft flies beyond certified load factor: Subject to permanent deformation
No effect Minor Major Hazardous Catastrophic
Qualitive None Probable Remote Extremely remote Extremely improbable
Quantative None 10-3 10-5 10-7 10-9
Flight crew None Slight workload Physical discomfort Physical distress Fatality/Incapacitation
Airplane margins None Slight reduction Significant reduction Large reduction Hull loss
Passengers Inconvenience Physical discomfort Physical distress Serious/fatal injury Multiple fatalities
Airframe
• Engine compartment decking & firewall: Stainless steel/titanium sheet
• Sandwich structure:
- Consists of two thin sheets separated with light core material
- Low mass high stiffness
- Stabilizes covering sheets
- Unsuitable for absorbing concentrated loads
- Does not use resin
• Composite structure:
- Consists of matrix & fibres
- Component strengths can be tailored to the direction of load, not the same in all directions
- Higher strength to weight ratio compared to other metal
• Truss type: Small light aircraft/training planes
• Monocoque:
- Takes all the load on a stressed skin
- Normally uses aluminium/magnesium alloy
• Semi-monocoque:
- Fuselage of transport airplanes
Downloaded by: nurse001 |
Distribution of this document is illegal
written by
nurse001
www.stuvia.com
Downloaded by: nurse001 |
Distribution of this document is illegal
, Stuvia.com - The Marketplace to Buy and Sell your Study Material
THE
PILOT
Aircraft
general
knowledge
ATPL
STUDENT
pilot
resume
all info you need to pass atpl exams
Downloaded by: nurse001 |
Distribution of this document is illegal
, Stuvia.com - The Marketplace to Buy and Sell your Study Material
AGK
System design, load, stress & maintenance
• Damage/fault tolerant design:
- Capability to withstand a certain amount of weakening of a structure without catastrophic failure
- Takes cracking of the structure into account
• Fail safe design:
- More than one load carrying component, parallel structural parts, load sharing
- Based on redundancy of components
- Does not imply that the system will never fail despite having backups
• Safe life design:
- Replacement of part after a given number of cycles/flight hours in use
- One load carrying component is sufficient provided it is strong enough
- Does not imply that the system will never fail in the safe life period
There is no most favourable design method, as each component varies
• Maintenance:
1. Hard time: Component overhauled/removed after a set number of hours/cycles regardless of condition
2. On condition: Monitoring of critical parameters & replacement of parts if a limit value is exceeded
• Stress: Force/area
1. Tension: Force resisting from being pulled apart
2. Torsion: Caused by twisting
3. Compression: Push force
4. Torque: Axial rotation force
5. Shear: Force parallel to cross section
6. Buckling: Effect of more than one force
• Strain:
- Deformation due to stress, expressed as a % change of dimension of original dimension
• Elastic deformation
- Tendency of material to return to its original state
- Temporary & reverses when load is removed
• Corrosion: Incorrect metallic bonding
1. Stress: Continuous tensile load + corrosion
2. Intergranular: Grain boundaries inside metal
• Fatigue: Material is continually loaded & unloaded & will eventually break even though load is the same
• Aircraft flies beyond certified load factor: Subject to permanent deformation
No effect Minor Major Hazardous Catastrophic
Qualitive None Probable Remote Extremely remote Extremely improbable
Quantative None 10-3 10-5 10-7 10-9
Flight crew None Slight workload Physical discomfort Physical distress Fatality/Incapacitation
Airplane margins None Slight reduction Significant reduction Large reduction Hull loss
Passengers Inconvenience Physical discomfort Physical distress Serious/fatal injury Multiple fatalities
Airframe
• Engine compartment decking & firewall: Stainless steel/titanium sheet
• Sandwich structure:
- Consists of two thin sheets separated with light core material
- Low mass high stiffness
- Stabilizes covering sheets
- Unsuitable for absorbing concentrated loads
- Does not use resin
• Composite structure:
- Consists of matrix & fibres
- Component strengths can be tailored to the direction of load, not the same in all directions
- Higher strength to weight ratio compared to other metal
• Truss type: Small light aircraft/training planes
• Monocoque:
- Takes all the load on a stressed skin
- Normally uses aluminium/magnesium alloy
• Semi-monocoque:
- Fuselage of transport airplanes
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