CPL Air Law · Mock exam

An aircraft departs a Class D aerodrome with a transponder set to 3000. ATC instructs 'squawk 4521.' The pilot must:

• A.Change to 4521 only after exiting the Class D control zone
• B.Ask ATC to confirm the code in writing before changing from the conspicuity code
• C.Select 4521 immediately without read-back, as transponder instructions do not require read-back
• D.Confirm 4521 back to ATC, then select 4521 on the transponder