40-41 Air Data Measurement Altimetry

Question 1

Errors & Corrections for altimetry

Answer 1

Instrument error

Position error

Lag or Hysteresis

Temperature error

Question 2

QNE

Answer 2

Q code designator for standard pressure

The altimeter sub-scale is set at the ISA pressure of 29.92” Hg

Question 3

QFE

Answer 3

Field elevation

Question 4

QNH

Answer 4

(Also known as altimeter setting)
Q code designator for the barometric pressure in millibars or inches of Hg for a particular time and place, adjusted to MSL according to ISA

Question 5

Indicated altitude

Answer 5

Altitude readout with QNH set on the altimeter sub-scale

Question 6

Pressure altitude

Answer 6

Altitude readout with QNE set on the altimeter sub-scale

Question 7

True altitude

Answer 7

Actual height above MSL

Obtained by correcting indicated altitude for temperature

Question 8

Absolute altitude

Answer 8

Actual height above terrain

Altitude readout with QFE set on the altimeter sub-scale (only at the aerodrome) or from radio or radalt