Tabletop 4

Navigation & Sectional Aeronautical Charts

 

1) Aeronautical Charts

 

A) When you are flying near a non towered airport such as Double Eagle, Mid Valley, or Belen.  How do you talk to the traffic in the area?  Use UNICOM.  DE Traffic this is HAB N7019C Bla Blab DE Traffic.

 

B) The big numbers within a section.  What do they mean?

C) AWOS – Automated Weather Observation Service

D) ATIS- Automated Terminal Information System

 

E) Setting your altimeter. What do you use to set it?  What about above 18,000?  What barometer setting do you use?  What is the airspace?  Can you fly there?

 

F) Restricted space?  Review it

 

G) On the map you are looking at what direction is the sun shining from?

 

F) VFR limits within classes of Air Space.  Learn it

 

2) Navigation

 

A)         Winds

 

WIND: Movement of air mass across the earth’s surface, expressed in                  direction FROM.

True Wind: Enroute winds from forecaster are TRUE from Winds-Aloft charts and Teletype Winds-Aloft Forecasts.

Magnetic Winds: Surface winds from Airport Traffic Control and Approach/Departure Control are MAG winds, and coincide with MAG direction of runways.

b) Conversion of True and Magnetic Winds

To convert wind direction from degrees with respect to true north to degrees with respect to magnetic north, or vice versa, the observer shall obtain the local magnetic variation from an aeronautical chart and proceed as follows:

1)  To convert from true to magnetic wind:

(a)  Add westerly variation to true direction (West is Best)

(b)  Subtract easterly variation from true direction

2)  To convert from magnetic to true direction:

(a)  Add easterly variation to magnetic direction

(b)  Subtract westerly variation from magnetic direction (West is Least)

c)     Plotting course Exercise:

1) You are doing a “long jump” and you launch your balloon at Willard, NM with winds aloft at 200 degrees at 20knots.  Assuming the winds stay constant, where will be the balloon’s approximate position by after 2 hours?

Winds aloft are given in TRUE direction they are out of, thus balloon is traveling 180 degrees in opposite direction or 20 degrees true.

Distance = Ground Speed x time or D = 20 K x 2 hours or D = 40 NM.

40 NM on a heading of 20 degrees TRUE places the balloon about 4 NM NE of White Lakes.

2)  Your balloon drifts over Cedar Crest on a magnetic course of 112 degrees at 25 MPH.  If the wind conditions remain the same, where will the balloon be after two hours?

     Note:  scale is in MPH or Statute Miles

Distance D = GS x T or D = 25 MPH x 2 or D = 50 miles (Statue)

Course is flying 112 degrees Magnetic and variation is 11 degrees East.  Therefore course is 112 M + 11 east.  Therefore, True course is 112 + 11 = 123 T