Direct Reading Instruments

Question 1

Agonic line

Answer 1

Places of zero variation

Question 2

NZ dip

Answer 2

61 to 72°
Therefore pendulous suspension

Question 3

Acceleration error

Answer 3

Greatest when east or west
Due to pendulous offset suspension
Acceleration points south
Deceleration north
SAND

Question 4

Turning error

Answer 4

Onus
Overread north underread south
30° north or south decreasing by 10 every 30 degrees
Brief
1. Current heading
2. Turn direction (L or R)
3. New heading
4. Overread underread
5. Roll out heading

Question 5

Tachometer

Answer 5

Indicates rotational speed of engine
Measure crankshaft rpm
Electric
Electronic
Mechanical (flyweights that pull together at faster speeds)
Drag cup(magnets creates eddys on drag cup which rotates cup through torque or drag until balanced

Question 6

Manifold pressure

Answer 6

Reads pressure at inlet manifold downstream of carb or fcu
In inches of mercury
Ensures engine power can be set accurately

Question 7

Direct oil pressure gauges

Answer 7

Bourdon tube straightens as pressure increases and indicates pressure

Question 8

Vacuum gauge

Answer 8

Also bourdon tube
When system pressure is applied tube increases curvature directly linked to pointer movement

Question 9

Fuel quantity gauge

Answer 9

Variable resistance
As fuel lowers resistance changes altering current indicating fuel level

Capacitance
Capacitance between fuel and air changes as fuel level decreases indicating fuel level

Question 10

Outside air temp

Answer 10

Bimetallic strip with different coefficients of expansion joined together
Responds to temp changes by twisting and unwinding or winding helix coil based on temo