Communications (Radiotelephony)
Standard phraseology
Know the ICAO radiotelephony alphabet (Alfa, Bravo, Charlie...), the pronunciation of numbers (tree, fife, niner), and standard phrases such as 'roger', 'wilco', 'standby', 'say again', 'affirm' and 'negative'. Understand the structure of a call: station called, your station, position, altitude, and intentions. Know the distress call 'MAYDAY' and the urgency call 'PAN PAN', and when each is used.
Frequencies and procedures
Know the emergency frequency 121.5 MHz, the use of the transponder, and the readback requirements for clearances. Understand the difference between a distress (grave and imminent danger) and an urgency (serious but not immediate) situation. Know the phonetic alphabet and how to spell out a registration. In Brazil, ANAC and DECEA publish the rules; ATC communications follow ICAO standard phraseology.
Traps
Questions confuse MAYDAY with PAN PAN, or ask which frequency is the emergency one (121.5 MHz). Another trap is the readback - pilots must read back clearances, especially runway and altitude instructions. Watch for items on the meaning of 'roger' (received) versus 'wilco' (will comply).
Worked example
To report a serious but non-immediate problem, use 'PAN PAN' three times; for grave and imminent danger, use 'MAYDAY' three times.