IFR » IR Air Law » Clearances
52.62.2 State the requirements for complying with ATC clearances and instructions. CAR 91 & AIP ENR
91.241 Compliance with ATC clearances and instructions
(A) A pilot of an aircraft operating in a control area or control zone designated under Part 71 must—
(1) except when manoeuvring in accordance with an ACAS resolution advisory or a GPWS or TAWS alert, comply with any ATC clearance or instruction issued by the ATC unit responsible for the control area or control zone; and
(2) when a deviation from an ATC clearance or instruction is required for the safe operation of the aircraft, notify ATC of the deviation as soon as possible.
(B) A pilot of an aircraft need not comply with an ATC clearance or instruction if compliance would cause the pilot to breach any rule in this Part.
(C) A pilot of an aircraft who elects not to comply with an ATC clearance or instruction under paragraph (b) must immediately notify the appropriate ATC unit of the non-compliance.
AIP ENR 1.1-12
8 ATC CLEARANCES