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A pilotmust adviseATC immediately if issued a clearancewhich requires the
useof navigation aids not available to the aircraft, or thepilot is not qualified
to use.
Air traffic clearances are aimed at keeping an aircraft in controlled airspace,
both laterally and vertically, if the pilot has so planned. If a pilot is in doubt
that the clearancewill keep the aircraft in controlled airspace, ATC should be
advised and an alternative clearancemay be requested.
A pilot, desiring to retain control area protectionduring climb inClassC or
ClassD airspace, shouldmaintain at least 500 ft above the lower limit of the
CTA steps.
A control instruction issued after a clearance is obtained amends the
appropriate item in the clearance.When there is any change in the clearance
limit and/or route specified in the initial clearance, a completely new clearance
will be issued.
Whenever a restriction or requirement has been imposed, and, subsequently,
a further restriction/requirement is imposed, the subsequent instructionwill
cancel all previous restrictions/requirements unless:
• all restrictions/requirements are restated; or
• the subsequent instructions is prefixed ‘FURTHERREQUIREMENT’.
At a controlled aerodrome, clearance for operation in an adjoining control area
is givenbefore departure.
clearances
3 – control l ed a i rspace