12 Descent Flashcards
Forces on an AC in the descent?
D = T + W sinγ
L = W cos γ
Descent Angle?
The angle of an airplane’s flight path (measured in degrees) with respect to Earth’s horizon.
Descent Gradient?
The ratio of vertical height lost to horizontal distance flown through the air. It’s expressed as a percentage.
Ground Gradient?
The ratio of vertical height lost to horizontal distance flown over the ground. Wind affects this gradient—headwinds increase it, while tailwinds reduce it.
Glide gradient?
Gradient = Height / Distance
Realtionship between drag and gradient?
The greater the drag the steeper the slope and the angle of the descent.
Therefore the descent gradient is steeper when drag increases.
For class B, What is the gross and net gradient?
How does mass affect the glide angle?
A heavier AC must glide at a higher speed to to be at Vmd beacsue the drag curve has moved up and to the right.
How does configuration effect the glide angle / gradient.
Flaps reduce the lift to drag ratio. This steepens the glide path, increases the glide angle and reduced the glide range.
How does config change the total drag curve and hence Vmd?
Increase in parasite drag. Drag curve moves left and up.
CDA?
Continous Descent Approach, aircraft stays higher for longer.
Effect of wind on descent?
Headwind decreeases the ground range and increases the glide angle.
A tailwind increases ground range and reduces the glide angle with respect to the ground,
What is the glide for maximum endurance?
Spend maximum about of time in the air. Maximum at Vmp, where the power required is minimum.
Descent angle and gradient between max range and endurance?
Effect of wind on endurance?
Wind doesnt affect glide endurnace.
A typical descent schedule?
The higher the cost index:
- The steeper the descent path, the higher the speed.
- The shorter the descent distance.
- The later the top of descent (TOD)
