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6 – i ndex
Note: Base turnsmaybedesignatedas beingmade either in level
flight orwhiledescending, according to the circumstances of
each individual procedure.
BlindTransmission:
A transmission fromone station toanother
station in circumstanceswhere two-way communication cannot be
established, butwhere it is believed that the called station is able to
receive the transmission.
BlockLevel:
A sectionof airspacewith specifiedupper and lower
limits ona specific track, inwhich cleared aircraft arepermitted to
manoeuvre.
Break-outProcedure:
Aprocedure initiatedon instruction from
aPrecisionRunwayMonitor (PRM) controller uponwhich apilot is
required todiscontinue an ILS approachand immediately commence
a turnof approximately 90degrees from the ILS course, climbing (or
descending) as instructedbyATC, in response toanaircraft deviating
from the adjacent ILS course.
Briefing:
The act of giving in advance, specific pre-flight instructions or
information to aircrew.
Broadcast:
A transmissionof information relating toair navigation for
which an acknowledgement is not expected.
Ceiling:
Theheight above thegroundorwater of thebaseof the lowest
layer of cloudbelow 20 000 ft coveringmore thanone-half of the sky.
CENSAR:
An automated centralisedSARTIMEdatabase software
packageusedbyATS tomanageSARTIMEs.
Centre:
Ageneric call-signused in theen route and area environment
which can includeAir TrafficControl, Advisory, Flight Information and
Alerting services, dependingon the classificationof airspace inwhich
the service is provided.
CirclingApproach:
An extensionof an instrument approach
procedurewhichprovides for visual circlingof the aerodromeprior to
landing.
Clearance Limit:
Thepoint towhich an aircraft is grantedan air traffic
control clearance.
definitions