Chapter 16B - Air Temperature

Question 1

The measurement of air temp is important for…?

Answer 1

• TAS
• The likelihood of engine/airframe icing
• Aircraft performance and flight planning calculations

Question 2

Three common temperature measurement methods?

Answer 2

• Thermal expansion - mercury and bimetal sensors
• Changing Resistance
• Thermocouples

Question 3

What are Ambient, OAT, SAT and COAT?

Answer 3

Temperature of non moving air outside the aircraft

Question 4

What is the principle of operation of a direct reading temperature probe?

Answer 4

The change in temp causes expansion/contraction which produces a measurable mechanical movement.

Known as Direct Reading.

Question 5

Remote Reading temperature probe uses?

Answer 5

Platinum

Question 6

TAT probe is?

Answer 6

Total Air Temperature Probe

Question 7

Total Air Temperature Probe - Aspirated, uses?

Answer 7

Bleed air is drawn from the compressor of the engine and blown through the probe. The resultant low pressure sucks air in through the probe, allowing temperature measurement to be taken while stationary on the ground.

Question 8

Total Air Temperature is?

Answer 8

Ambient Temperature plus all the ram rise (Friction)

Question 9

What is Ram Rise?

Answer 9

Due to Kinetic Effects - TAT is higher than SAT

Question 10

How can you calculate the SAT from the TAT?

Answer 10