Altimetry

Question 1

What is height?

Answer 1

The vertical distance between the aircraft and a given surface

Question 2

What is altitude?

Answer 2

The vertical distance between an aircraft and the MSL

Question 3

What is elevation?

Answer 3

Vertical distance between a point on the earths surface and MSL

Question 4

What is indicated altitude?

Answer 4

The reading on the altimeter when it is set to local pressure at MSL

Question 5

What is true altitude?

Answer 5

The actual vertical distance above MSL

Question 6

What is the pressure altitude?

Answer 6

The height of the aircraft above the standard pressure datum 1013.25hPa

Question 7

How are flight levels determined?

Answer 7

By magnetic track

Question 8

What flight levels do VFR aircraft fly at?

Answer 8

Track of 0 degrees to 179 degrees, odd number + 500 e.g FL55

Track of 180 degrees to 359 degrees, even number + 500 e.g FL65

Question 9

What flight levels do IFR aircraft use?

Answer 9

Track of 0 degrees to 179 degrees, odd number e.g FL50

Track of 180 degrees to 359 degrees, even number e.g FL60

Question 10

What is the transition altitude?

Answer 10

The level at which you begin to use standard pressure setting on departure

Question 11

What is the transition level?

Answer 11

The level at which you begin to use QNH on approach

Question 12

What is the gap between the transition altitude and transition level called?

Answer 12

The transition layer

Question 13

What happens to indicated altitude when you change from a higher QNH to SPS?

Answer 13

Indicated altitude decreases

Question 14

What happens to indicated altitude when you change from a lower QNH to SPS?

Answer 14

Indicated altitude increases

Question 15

What happens to the true altitude if the pressure is sloped upwards as you travel?

Answer 15

It increases

Question 16

What happens to the true altitude if the pressure is sloped downwards as you travel?

Answer 16

It decreases (from high to low look out below)

Question 17

When would you use area QNH?

Answer 17

When flying cross-country

Question 18

When would you use aerodrome QNH?

Answer 18

When arriving or departing an aerodrome

Question 19

What happens to your true altitude when you fly from cold to warm on a constant pressure setting?

Answer 19

It increases

Question 20

What happens to your true altitude when you fly from warm to cold on a constant pressure setting?

Answer 20

It decreases

Question 21

What is the equation for temperature error correction (TEC)

Answer 21

TEC = height/1000 x 4 x ISA deviation

Question 22

How do we apply TEC when the ISA deviation is warmer?

Answer 22

Add the TEC to the indicated to get the true

Subtract the TEC from the true to get the indicated

Question 23

How do we apply TEC when the ISA deviation is colder?

Answer 23

Subtract the TEC from the indicated to get the true

Add the TEC to the true to get the indicated