【How-to】What is the purpose of q codes

Codes in the range QAA–QNZ are reserved for aeronautical use; QOA–QQZ for maritime use and QRA–QUZ for all services. “Q” has no official meaning, but it is sometimes assigned with a word with mnemonic value, such as “Queen’s” (e.g. QFE: Queen’s field elevation), “Query”, “Question”, or “reQuest”.