How to figure out TAS - True Air Speed

Types of Air-Speeds

1. Indicated Airspeed - Read directly on the Airspeed Indicator instrument
2. Calibrated Airspeed - Airspeed corrected for installation and instrument error
3. True Airspeed - Calibrated Airspeed corrected for variation of Temperature and pressure  and is used for flight planning purposes

White Arc 
 - Flap operating range of aircraft
- Vso top of arc velocity stall in landing configuration
- Vs1 - flaps up , stalling speed in a clean configuration
-   Vse bottom of arc maximum speed flaps extended

Green Arc
- normal operating of aircraft
- bottom of arc VN0 -  Maximum speed - normal operation

Yellow Arc
caution range

Red Line 

You can use

1. Use the POH
2. E6B
3. Use Airspeed Indication in the aircraft 

To get the True airspeed directly from the Airspeed Speed Indicator,

you need to get

1. The outside air temperature  Devtron Outside Air Temperature/Clock   
2. The pressure Altitude  - Set Barometric pressure to 29.92 and read the pressure altitude directly from the scale
3.  Adjust the knob so the Pressure Altitude matches the Outside Air Temperature
4. Read the true airspeed directly from the outer number of the white scale on the Airspeed Indicator

Outside Air Temperature 

Set Standard Pressure 29.92 - and Read Pressure Altitude directly from the Barometer gague

Adjust Knob at the bottom of the Gauge so that the Pressure Altitude 6600
matches the outside Temperature of 29.92   

Read the Outside scale directly to get the True Airspeed

https://www.youtube.com/watch?v=Qd1oCqzJZPM

How To Find Calibrated Airspeed CAS - E6B  (instrument exam question)

What CAS must be used to maintain the filed TAS  at the flight plan altitude if the outside air temperature is + 8 Degrees Centigrade  anerwer 157

So you have to get 3 things to calculate Calibrated Air Speed
1. Cursing Altitude   = 8,000 feet   (from Flight Plan)
2. True Air Speed  = from Flight plan 180Knots
3. Outside Air Temperature - Given in question  +8 deg C

line up the pressure altitude and temperature Zero

Now rotate and set up 8000 feet pressure altitude at the 0 deg C mark

now set the +8 degree

After align Altitude  8000feet to True Air Temperature -8 deg , you will set your true airspeed  which is 180 knots

It gives you 157 Calibrated Airspeed!