Forces In Descent

Question 1

What is the descent angle

Answer 1

Angle between ac path through the air and local horizontal
Symbol y (gamma)

Pitch angle + AOA

Question 2

What is the pitch angle

Answer 2

Angle between longitudinal axis and horizontal (shown on attitude indicator)
Pitch angle is less than the descent angle

Given as a negative value

Question 3

Forces in descent parallel to flight (power on)

Answer 3

Drag = Thrust + W Siny

Thrust
Drag
Wsiny

Question 4

Steeper descent will have a

Answer 4

Larger descent angle

Question 5

Shallowest descent is at

Answer 5

VMD

Question 6

Engine failure you will fly at…

Answer 6

Vmd for shallowest descent

Question 7

Vx

Answer 7

Best angle of climb
Steepest climb angle
Operate most efficient at heigh
Slow speed

Question 8

How do we manage drag

Answer 8

Speed and spoilers

Question 9

Depressurisation what speed should you fly at

Answer 9

VMO for most excess drag

Question 10

Drag in a descent formula

Answer 10

T + weight x siny = drag

Question 11

WSINY =

Answer 11

Drag - Thrust
——————
Weight

Question 12

In a glide descent forward component is what to drag

Answer 12

Equal as no thrust

Question 13

Calculating glide range

Answer 13

X lift by the range altitude
Convert ft to nm (6080ft in 1nm)

Question 14

Gliding with head wind

Answer 14

Range reduces

Question 15

Gliding with tailwind

Answer 15

Range increases

Question 16

Mass impact on glide range

Answer 16

Does not affect in still air heavy ac will simply just reach ground quicker in same location

Question 17

Heavy A/C in headwind glide range

Answer 17

Will be in air less time therefore less effected so slightly better range than a lighter ac

Question 18

Tailwind and mass

Answer 18

Light a/c will have greater range due to being in air longer

Question 19

X2 Factors effecting glide range

Answer 19

Flaps - reduce L/D ratio and glide range
Speed - flying faster or slower than vmd

Question 20

Glide endurance speed is

Answer 20

Vmp (0.76 vmd)
Useful for gliding over sea
Vmp is the minimum speed for power

Question 21

AOA is always expressed as

Answer 21

A positive number of degrees

Question 22

Pitch angle is always

Answer 22

Negative

Question 23

In steady power off descent which force drive ac down descent flight path?

Answer 23

Weight

Question 24

CDFA Is + advantages

Answer 24

Continuous descent final approach

Certain power setting all the way down the descent saves fuel/reduces engine wear and reduces air and noise pollution

Question 25

Glide angle of descent is the ratio of

Answer 25

Height lost to the horizontal distance travelled

Question 26

Best glide gradient factors

Answer 26

Vmd
Best L/D ratio
CLMAX/CD

Question 27

Formula for descent angle

Answer 27

Pitch Angle + AOA
(Always negative) (always positive)

Question 28

How does calculating angle of descent differ from calculating angle of climb

Answer 28

Angle of descent uses = siny = drag - thrust
—————-
Weight

Angle of climb uses = siny = thrust - drag
——————
Weight

Question 29

Calculating drag/weight or descent angle in powered off glide

Answer 29

Siny = drag
——-
Weight

Question 30

Glide range formula

Answer 30

Height x L/D ratio

Question 31

Glide range formula with winds

Answer 31

Glide range in still air x ground speed/original TAS

Question 32

Mass on glide range

Answer 32

Heavy ac will glide same distance if both fly at Vmd
More induced drag on heavier so has to fly faster vmd so will reach ground quicker

Question 33

Flaps and landing gear on glide range

Answer 33

Reduces due to increased drag
Steeper glide path and reduced endurance

Question 34

Headwind will do what to glide range

Answer 34

Reduce distance covered over the ground
Does not effect rate of descent

Question 35

Tailwind on glide range

Answer 35

Increase our speed
Cover more distance
No effect on endurance

Question 36

Shallowest glide angle is achieved when aircraft is gliding

Answer 36

At the speed which equates to best L/D ratio

Question 37

Which force drives ac down the descent angle in power on and off descent?

Answer 37

Weight

Driving factor for an aircraft down the descent flight path

Question 38

On a drag polar curve where is VMP to VMD

Answer 38

VMD is always below VMP on a CL/CD graph