Compressor stall:
210 Restriction of advertising of commercial operations
(1) A person must not give a public notice, by newspaper advertisement, broadcast statement or any other means of public announcement, to the effect that a person is willing to undertake by use of an Australian aircraft any commercial operations if the last‑mentioned person has not obtained an Air Operator’s Certificate authorising the conduct of those operations.
Penalty: 10 penalty units.
(2) An offence against subregulation (1) is an offence of strict liability.
Note For strict liability, see section 6.1 of the Criminal Code.
and from the Oxford dictionary:
Definition of advertisement
noun
a notice or announcement in a public medium promoting a product, service, or event or publicizing a job vacancy: advertisements for alcoholic drinks
(advertisement for) informal a person or thing regarded as a means of recommending something: unhappy clients are not a good advertisement for the firm
Origin: late Middle English (denoting a statement calling attention to something): from Old French advertissement, from the verb advertir (see advertise)
Just a "little thing" I know, but remember Direct Air and CAR 206.