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> by the time you receive an IFF query, you know you're about to be shot at

I don’t think that’s the most common case for an IFF query. AWACS oversight aircraft likely issue more IFF queries than fighter intercepts do. You still want to respond to a friendly AWACS inquiry, even though that aircraft is 100nm away and no direct/immediate threat to you.

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100nm (more or less) is the positive identification radar advisory zone for a carrier group airspace... (AKA REDCROWN)

Less than 100 nanometers?

It always gets me when someone abbreviates nautical miles in lowercase even though context is (almost) always clear it can't be nanometers.

An AWACS aircraft within 100 nanometers of you would indeed represent a direct and immediate threat. :)

TIL that nm isn’t actually accepted as an abbreviation for nautical miles. (It’s used so commonly in aviation that I assumed it was correct and it took me 3 or 4 searches to accept that this thing I knew was correct actually wasn’t. Thanks [seriously]!)

Same when people use “mhz” for megahertz

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