#MILITARY RADIO LINGO FULL#

Industry Canada (formerly Transport Canada) guidance on radio checks as per Radiocom Information Circular 21 section 5.7.5 (the study guide if you want to get a restricted operators certificate with aeronautical qualification). Most people forget this though as modern radios are pretty good about not doing that, and the only issue is weaker than normal signals. A strength of 5 is normal – if it were something higher it would mean you were overpowering the transmitter and overloading receiving speakers or something. To resolve this ambiguity problem, in Australia the required response to a radio check question is something like, “strength 5, readability 4”.īy the way, the strength is supposed to be on a scale of 1-10. After all, the catchphrase “loud and clear” would mean that strength comes first and readability second, right? I actually think this is the more common method, not the method Sarah suggests, but it’s certainly ambiguous.

There is a lot of disagreement as to which number is which – I’ve seen dozens of references to both. A weakish signal that is otherwise readable would be ‘5 x 3’ after your correction.

#MILITARY RADIO LINGO FULL#

For example it might be full of crackles and pops, or a bad microphone, or background noise, or something like that – but still fully loud and strong. So you didn’t fully correct your blog post, because if the reading were “3 x 5” and the first number is readability, that would mean a maginally readable signal but perfectly loud/strong. Remember that on AM radio, which includes aircraft bands, signal strength and volume (loudness) are equivalent. There seems to be a lot of confusion on which number is which. So now you too know the meaning of the term “Five by Five”. So when you say to the controller (or pilot) “5 by 5”, it is literally another way of saying that the transmitter you hear is “loud and clear.” If you say “3 by 5” it’s like saying, “Your coming in kind of weak, but I can still make out what your saying” Signal strength and readability are measured on a five point scale with 5 being the highest value possible and 1 being the lowest. Well, thanks to my local tower controllers, I learned that the first number is for signal strength and the second number is for readability. Ok, so what transmission quality is represented by the “3” and what is represented by the “5”. I wanted to find out exactly what is meant by that term “5 by 5” when I heard an aircraft respond to a radio check by saying: Well, I’ve heard this term used countless times and it was a recent transmission that finally motivated me to do some research. “Citation XYY, how do you hear this transmitter?” Have you ever wondered what is meant by the term “Five by Five?” You’ll hear this sometimes as a response when an aircraft or tower is asking for a radio check:

Military radio lingo