Section 5: Radio Communications — Listen Always, Transmit Never (Except One Emergency)

Aviation transmission requires licensing a remote pilot doesn't hold; keying up is an FCC violation, full stop. The whole value is one-directional: LISTENING to ATC and CTAF around your operating area tells you who's inbound, which runway is active, and when final is occupied - spatial awareness no app matches for latency. The lone exception: a true emergency (his example: a rogue drone penetrating controlled airspace near traffic), where declaring on the radio is permitted.

The ICAO alphabet is planet-wide - he used the same one flying in France. Two digits change sound: 3 = 'tree', 9 = 'niner' (0 stays 'zero', never 'oh'). Numbers unravel digit by digit: 4,500 = 'four thousand five hundred'; 10,500 = 'one zero thousand five hundred' - ten, eleven, twelve 'don't exist' on the radio. Runway zero-nine, not runway nine. Frequencies take 'point': 122.1 = 'one two two point one'. Altitudes spell out fully below 18,000 MSL; above that, flight levels drop the last two zeros - 20,000 becomes 'flight level two zero zero'. Headings and speeds: always digits ('zero niner zero', 'three two zero knots').

Traffic calls use the aircraft's own nose as 12 o'clock: 3 is right, 6 behind, 9 left - all relative to HEADING, not north. Call signs are registration numbers ('tail numbers'), fronted by 'November' for US general aviation: first contact uses the full sign ('November one two three Alpha Bravo'), then everyone may clip to the last three ('three Alpha Bravo'). Jets may swap 'November' for the type ('Citation 570 Lima Tango'); airlines use flight numbers ('United 146'). The FAA's sample question runs the clock logic: heading 360, 'traffic ten o'clock' = left-forward quadrant, converging.

Position calls at untowered airports are optional: 'they should be making radio calls, but they don't have to' - so silence proves nothing; keep your eyes working. The channels: UNICOM is a person on the field (often weekends only) answering requests - active runway, wind, pattern count - with no control authority. CTAF is the self-announce channel, sometimes the same frequency as UNICOM, and at part-time towered fields the TOWER frequency becomes the CTAF after closing. No CTAF or UNICOM listed? The nationwide Multicom: 122.9. Flight Service Stations, the old briefing infrastructure, have been 'closing left and right' as services moved online.

The worked pattern at 'Sedona' (fictional), Cessna 123 Bravo Foxtrot, runway niner: 'Sedona traffic, Cessna 123 Bravo Foxtrot, 10 miles south, inbound for landing, Sedona traffic' - then entering midfield left downwind, base, final, clear of runway, departing - all bracketed the same way. The double name exists because CTAF frequencies are shared regionally; you must know WHICH airport's pattern you're hearing.

Towered fields invert the flow: ATC directs ('enter left downwind runway niner', 'you're number two following the Piper on final') and pilots READ BACK each instruction verbatim - the readback is the confirmation layer. He recommends a cheap handheld scanner for field listening.

Sectional decode: 'CT' precedes the control-tower frequency (Prescott: 125.3), a star means part-time; UNICOM appears separately (122.95 there - used for fuel and services). The Chart Supplement gives tower hours in Zulu and confirms the after-hours arrangement: tower closed, same 125.3 becomes the CTAF. Untowered fields mark CTAF with a 'C' suffix (his example 122.7 C). The exam's staged versions: Dallas Executive after-hours CTAF 127.25; Kirtland CTAF 122.8 sitting right next to an AWOS frequency on the same figure - the flagged trap being reading the weather station's number as the traffic frequency.