test 1, pp 3: magnetic compass
What is it called when an airplanes speed affects the magnetic compass?
Acceleration and decceralation errors
Magnetic north pole
An area pointed to by a compass based on the Earth's magnetism. This location will change over time.
How do you calculate compass headings?
Converting from degrees true to degrees magnetic using variation and to our compass heading, using deviation.
True heading of 136 to a compass heading when the variation is 19 degrees west and the deviation is 3 degrees east
Magnetic heading of 155 degrees, and compass heading of 152 degrees
Variation
The angular difference between true north and magnetic north from any given position on the earth's surface
True north
The direction to the geographic North Pole
Isogonic line
The line connecting points at which there is no variation between true and magnetic north
Deviation
The metal in the airplane (and the radios and other equipment) affect the compass so that it doesn't correctly point north
Northerly Turning Error
When turning away from the magnetic North Pole, the compass lags. When turning towards the magnetic North Pole, the compass leads
The actual value of the variation angle is marked by a _______ on the chart
dashed magenta line
The magnetic compass is used to _____
determine magnetic heading
East is _____
least (-)
isogonic lines
marked by broken magenta lines which connect points of equal magnetic variation
Magnetic north
the direction that the needle of a magnetic compass points
West is best, and east is least is only used from ______ to _____
true to magnetic
Compass heading to true heading
west is least, east is best
Acceleration error (magnetic compass)
will cause the compass to briefly show a turn north.
The deviation is written on a ____
compass correction card, which the pilot takes into account while planning flights
Deceralation error (magnetic compass)
Will cause the compass to show a turn south
West is _____
best (+)
