DESCENT AND GLIDING

Question 1

What are the forces in a Steady Glide?

Answer 1

Drag = Thrust + WAT

Question 2

How is glide angle increased?

Answer 2

By increasing the drag component

Greater drag means that WAT component has to increase, which then increases the angle of descent

Question 3

What’s the speed for minimum angle of descent and when will min angle be smallest?

Answer 3

It’s Vmd.

Will be smallest when drag is smallest

Question 4

What’s the speed for max angle of descent and when will max angle be highest?

Answer 4

Speed is at an as high speed as possible limited by drag devices
Max angle is highest when the drag is greatest

Question 5

Does weight have any influence on max angle of descent?

Answer 5

No

Question 6

Why can i be bad to use gear and flaps to try to get max angle of descent?

Answer 6

Because the benefit of extending gear and flaps is usually offset by a large reduction in parasite drag at the often much slower limiting speeds Vfe and Vlo
Speed for max angle of descent is therefore usually type specific

Question 7

Speed for minimum rate of decent?

Answer 7

Speed for minimum descent is Vmp.
A/c has a slightly steeper angle of descent at Vmp but the much slower speed at Vmp compared to the “more” correct Vmd (0,76 of Vmd) results in a lower (minimum) rate of descent

Question 8

What does min rate of descent depend on?

Answer 8

Depends on the angle of descent and the speed along it’s path

Question 9

What’s the speed for max rate of descent?

Answer 9

Both angle and speed down the path needs to be as large as possible
Speed is at a fast speed, but limiting by speed limits for drag devices

Question 10

What are the forces in a glide?

Answer 10

In a glide there’s no thrust, only WAT

Question 11

What is needed to achive max glide and what’s the speed for max glide?

Answer 11

L/D ratio must be max so the speed for max glide is therefore Vmd

Question 12

How does the following factors affect glide?

1. Weight
2. Configuration
3. Wind

Answer 12

1. Weight:
   Doesn’t affect glide as long as we fly at Vmd
   If it does it has the same L/D ratio and same glide angle and range
   Speed increases with weight cause the drag curve has moved up- and right
   A heavier aircraft has to glide at a faster speed to be at Vmd
2. Configuration:
   Reduces L/D ratio, which will steepen the glide path angle and therefore reduces glide range
3. Wind:
   HW decreases ground range and increases the glide angle
   TW increases ground range and reduces the glide angle