THE
PILOT
Principles
of flight
ATPL
STUDENT
pilot
resume
all info you need to pass atpl exams
, POF
General:
Bernoulli: Sum of all energy constant
3
Temperature ~ density(rho)[kg/m ]
Density ∝ mass
Density ∝ pressure
Density does not vary in venturi
Density decrease as humidity increase
Temp ↑ mass flow ↓
2
Dynamic pressure [q]( N/m )
1 2
= / 2 ρV(TAS)
Dynamic press = 0 when speed = 0
Static + dynamic = constant
p/(rho*T) = Constant
• SI units:
- Weight (Newton) = Force = Mass(kg) x acceleration
- Power (Nm/s) = Watts (W) Force x distance ÷ time (J/s) [There is time]
- Work = Joule
2
- Force [kg.m/s ]= m x a
2
- Wing loading[W/S](N/m ): Weight of aircraft ÷ area of the wings
• Density decrease with increase in humidity (Dry air = better performance)
• Mean geometric chord: Wing area ÷ wing span
Difference between MAC & mean camber line
Relative thickness: Expressed in % chord
Symmetrical airfoil: 0 camber, mean camber line = chord line
& lift characteristics as the actual wing
• Aeroplane AOA: Angle between speed vector & longitudinal axis
Wing AOA: Angle between longitudinal axis & wing root chord line
Angle of incidence: Angle between wing root chord line & longitudinal axis
Dihedral angle:
- Angle between wing plane & the horizontal with aeroplane in an unbanked , level condition
- Angle between the 0.25 chord line of the wing and the lateral axis
• Lift & drag forces depend on the pressure distribuition around the aerofoil cross section
• Lift = Component of total aerodynamic force perpendicular to the undisturbed airflow
2D airflow over an aerofoil
o
• Typical C L /C D ratio: Max at angle of attack of 4
• Lift:
- Upwash ahead of the wing & downwash behind
- Downwash increase: Lift generated by the aerofoil increases
- Upper surface produces greatest proportion of lift at all speeds
- Generated when the flow direction of a certain mass of air is changed
• Stagnation point:
- Static pressure maximum value
- Relative velocity = 0
• AOA
- Decrease: Stagnation point moves forward /up, lowest pressure(CP) moves aft, COP moves aft
- Increase: Stagnation point moves down, lowest pressure(CP) moves forward, COP moves forward until crit AOA
• Aerodynamic centre of an aerofoil:
- Approx 25% chord irrespective/independent of AOA
- Assume no flow separation, pitching moment coefficient does not change with carying angle of attack
PILOT
Principles
of flight
ATPL
STUDENT
pilot
resume
all info you need to pass atpl exams
, POF
General:
Bernoulli: Sum of all energy constant
3
Temperature ~ density(rho)[kg/m ]
Density ∝ mass
Density ∝ pressure
Density does not vary in venturi
Density decrease as humidity increase
Temp ↑ mass flow ↓
2
Dynamic pressure [q]( N/m )
1 2
= / 2 ρV(TAS)
Dynamic press = 0 when speed = 0
Static + dynamic = constant
p/(rho*T) = Constant
• SI units:
- Weight (Newton) = Force = Mass(kg) x acceleration
- Power (Nm/s) = Watts (W) Force x distance ÷ time (J/s) [There is time]
- Work = Joule
2
- Force [kg.m/s ]= m x a
2
- Wing loading[W/S](N/m ): Weight of aircraft ÷ area of the wings
• Density decrease with increase in humidity (Dry air = better performance)
• Mean geometric chord: Wing area ÷ wing span
Difference between MAC & mean camber line
Relative thickness: Expressed in % chord
Symmetrical airfoil: 0 camber, mean camber line = chord line
& lift characteristics as the actual wing
• Aeroplane AOA: Angle between speed vector & longitudinal axis
Wing AOA: Angle between longitudinal axis & wing root chord line
Angle of incidence: Angle between wing root chord line & longitudinal axis
Dihedral angle:
- Angle between wing plane & the horizontal with aeroplane in an unbanked , level condition
- Angle between the 0.25 chord line of the wing and the lateral axis
• Lift & drag forces depend on the pressure distribuition around the aerofoil cross section
• Lift = Component of total aerodynamic force perpendicular to the undisturbed airflow
2D airflow over an aerofoil
o
• Typical C L /C D ratio: Max at angle of attack of 4
• Lift:
- Upwash ahead of the wing & downwash behind
- Downwash increase: Lift generated by the aerofoil increases
- Upper surface produces greatest proportion of lift at all speeds
- Generated when the flow direction of a certain mass of air is changed
• Stagnation point:
- Static pressure maximum value
- Relative velocity = 0
• AOA
- Decrease: Stagnation point moves forward /up, lowest pressure(CP) moves aft, COP moves aft
- Increase: Stagnation point moves down, lowest pressure(CP) moves forward, COP moves forward until crit AOA
• Aerodynamic centre of an aerofoil:
- Approx 25% chord irrespective/independent of AOA
- Assume no flow separation, pitching moment coefficient does not change with carying angle of attack
