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6 – i ndex
CruiseClimb:
An aeroplane cruising technique resulting inanett
increase in altitude as the aeroplaneweight decreases.
Cruising Level:
A levelmaintainedduringa significant portionof a
flight.
DangerArea:
Anairspaceof defineddimensionswithinwhich
activities dangerous to theflight of aircraftmay exist at specified
times.
Day:
That periodof time from thebeginningofmorning civil twilight to
theendof evening civil twilight.
DeadReckoning (DR) Navigation:
The estimatingor determiningof
positionby advancing an earlier knownpositionby the applicationof
direction, time and speeddata.
DecisionAltitude/Height (DA/H):
A specified altitudeor height in
theprecisionapproach atwhich amissed approachmust be initiated
if the required visual reference to continue the approachhas not been
established.
Note 1: ‘Decision altitude (DA)’ is referenced tomean sea level (MSL)
and ‘decisionheight (DH)’ is referenced to the threshold
elevation.
Note 2: The ‘required visual reference’means that sectionof thevisual
aids or of the approach areawhich shouldhavebeen in view
for sufficient time for thepilot tohavemade anassessment
of the aircraft position and rateof changeof position, in
relation to thedesiredflight path.
DensityHeight:
An atmospheric density expressed in terms of height
which corresponds to that density in theStandardAtmosphere.
DependentParallelApproaches:
Simultaneous approaches to
parallel instrument runwayswhere radar separationminimabetween
aircraft on adjacent extended runway centre-lines areprescribed.
DistanceMeasuringEquipment (DME):
Equipmentwhich
measures innauticalmiles, the slant rangeof an aircraft from the
selectedDMEground station.
DMEDistance:
The slant range from the sourceof aDME signal to the
receiving antenna.
definitions