Temperature and Pressure Measurement

Question 1

How to calculate degrees Fahrenheit from degrees celsius?

Answer 1

Degrees celsius x 9/5 + 32

Question 2

How to calculate degrees celsius from degrees Fahrenheit?

Answer 2

Degrees Fahrenheit x -32 x 5/9

Question 3

How to calculate degrees absolute/Kelvin from degrees celsius?

Answer 3

Degrees celsius +273

Question 4

Define “Static Air Temperature”

Answer 4

SAT, or OAT, or ambient air temperature, is the free air static temperature obtained either from ground met sources or from in-flight temperature readings corrected for instrument error and compressibility(No ram rise)

Question 5

Define “Ram Rise”

Answer 5

The increase in temperature sensed due to compressibility

Question 6

Define “Ram Air Temperature”

Answer 6

SAT/OAT plus a percentage of the rise in temperature due to ram compression. If a particular temp sensor have a recovery factor of 0.80, the sensor will measure the ambient outside air temperature plus 80% of the RAM rise.

Question 7

Define “Total Air Temperature”

Answer 7

Outside air temperature plus 100% of the rise in temperature due to ram compression

Question 8

Is SAT and OAT the same?

Answer 8

Yes

Question 9

Under what mach speed is ram rise ignored for practical purposes?

Answer 9

Ram rise under mach 0.30 is negligible

Question 10

The other name for TAT?

Answer 10

IOAT

Question 11

What is the RAM RISE equation?

Answer 11

Ram Rise = (V/100) squared

Question 12

For what type of temperature reading is a Rosemount Probe used?

Answer 12

For reading TAT, or true RAT.

Question 13

For what type of temperature reading is a Lewis Flush Bulb used?

Answer 13

RAT

Question 14

The thermometer that use differential expansion of two different metals as a method for reading temperature, this thermometer is called?

Answer 14

A direct reading low speed Bi-Metallic thermometer

Question 15

The thermometer that use contraction and expansion of a liquid or gas, due to temperature change, as a method of reading is called?

Answer 15

The Bourdon Tube Thermometer

Question 16

Explain how the aneroid capsule works, and is used for what spectrum of pressures?

Answer 16

The sealed capsule contains a partial vacuum, any reduction in external pressure would cause the capsule to expand and any increase in pressure will cause the capsule to contract, used mainly for low pressures.

Question 17

Explain how the pressure capsule works

Answer 17

In this case the capsule is not completely sealed, but has an opening which may be connected to a pressure source which causes the capsule to expand or contract

Question 18

The type of system used for measuring the difference between two pressure readings?

Answer 18

The bellows system

Question 19

The system used for relatively high pressures associated with oxygen, hydraulic or engine oil pressure systems?

Answer 19

The bourdon tube.

Question 20

A pressure capsule is one that receives?

Answer 20

Dynamic Pressure

Question 21

Is an aneroid capsule and a pressure capsule the same?

Answer 21

No

Question 22

Which type of measurement instrument is used for both pressure and temperature?

Answer 22

The bourdon tube

Question 23

Mach number is the ratio between?

Answer 23

TAS and the local speed of sound

Question 24

If Mach number = 1.00 TAS equals?

Answer 24

The speed of sound

Question 25

If Mach number = 0.70 TAS equals?

Answer 25

70% of the speed of sound

Question 26

As altitude increases speed of sound?

Answer 26

Decreases

Question 27

How to calculate the mach number ratio?

Answer 27

TAS / speed of sound = Mach number

Question 28

At a constant mach number, if altitude is increased TAS will?

Answer 28

Decrease

Question 29

RAT will equal SAT when?

Answer 29

The aircraft is stationary, SAT/OAT is the undisturbed free air temperature unaffected by RAM rise. IOAT is the same as TAT. TAT is the SAT/OAT + 100% of the RAM rise.

Question 30

RAT = SAT when:

TAT = RAT when:

Answer 30

There is no ram rise

The recovery factor is 100%