Chapter 2 - Air / Airspeed

Question 1

The mass of a gas is?

Answer 1

It’s density = 1.225 kg/m^3

Question 2

How do we get mass flow round an a/c?

Answer 2

Speed x Cross sectional area x density

Question 3

Air density decreases if

Answer 3

Px decreases
Temp increases
Humidity increases

Question 4

AD can proportional to

Answer 4

AD proportional to P/T

Question 5

Static pressure is measured in

Answer 5

N/m^2, Is known as row (P)

Question 6

As you increase altitude Static pressure will?

Answer 6

Decrease

Question 7

Cold day = for density

Answer 7

More dense

Question 8

0 kelvin =

Answer 8

Absolute 0 = no molecule movement

Question 9

If the Viscosity is high =

Answer 9

Thick - syrup like

Question 10

Why is humid air less dense

Answer 10

Because Air molecular weight is much more and when the WV starts occupying the space as well it makes the air less dense.

Question 11

What does high humidity do to density

Answer 11

Decreases it

Question 12

Which height is the air pressure half and 25%

Answer 12

18,000

34,000

Question 13

Which height is the density half and 25%

Answer 13

20,000 feet

40,000 feet

Question 14

In terms of physics how can a/c stay airborne

Answer 14

If the work on the air is enough to oppose the force of gravity

Question 15

If we want to know how much force an aircraft can generate - what do we need to know

Answer 15

speed and air density

Question 16

TAS =

Answer 16

True Airspeed - the speed at which the aircraft is passing through the air

Question 17

Dynamic pressure =

Answer 17

1/2 density of the air x TAS^2

Question 18

The force generated by dynamic pressure can become?

Answer 18

very large

Question 19

If we increase density - dynamic pressure will

Answer 19

increase

Question 20

If we increase TAS - dynamic pressure will

Answer 20

increase rapidly - x4

Question 21

What is dynamic proportional to

Answer 21

IAS

Question 22

How does a IAS work

Answer 22

Basic Total Px minus Static = Dynamic

Dynamic Px enters a pitot tube and is tubed to the IAS where it goes into a capsule.
Surrounding the capsule is static Px

Question 23

What is instrument error?

Answer 23

Errors caused by the limitation of the manufacturing process

Question 24

What are Pressure errors

Answer 24

Because of the position or orientation of the pitot or static port doesn’t receive all of the airflow

Question 25

What are compression errors

Answer 25

When travelling at high speed the air can compress in the pitot tube therefore artificially raising the density

Question 26

What is CAS

Answer 26

Calibrated Airspeed - which is correct for instrument and pressure errors via an Air data computer

Question 27

What is EAS

Answer 27

Equivalent Airspeed - which is corrected for compression errors

Question 28

At low speeds what is the difference between CAS,EAS and IAS

Answer 28

Small but bigger at high speeds

Question 29

ICE Tea is Pretty Cool Drink

Answer 29

Gives the order for airspeeds