What CAP 413 is
CAP 413 is the Civil Aviation Authority's Radiotelephony Manual — the UK reference for how voice communication works on aeronautical frequencies. It defines the standard words and phrases ("wilco", "say again", "hold position"), how callsigns are used and abbreviated, the shape of routine calls from taxi to landing, what must be read back, and the priority phraseology for urgency and distress. When an examiner assesses your radio work for the FRTOL, CAP 413 is the standard they're marking against.
What's inside — the student pilot's view
The manual covers everything from gliders to airline operations, but a PPL/FRTOL candidate leans on a much smaller core:
- Standard words, letters and numbers — the phonetic alphabet and how numbers are spoken. Our phonetic alphabet guide covers this.
- Callsigns — placement, when they may be abbreviated, and the STUDENT prefix.
- Message structure — who you're calling, who you are, where you are, what you want.
- Mandatory readbacks — clearances, runway, pressure settings, frequencies and more. Full readbacks guide.
- Aerodrome and circuit phraseology — taxi, departure, joins, downwind/final calls, go-arounds.
- Services and airspace — Basic/Traffic services, zone transits, MATZ penetration.
- Emergencies — MAYDAY and PAN PAN format, relay, and radio failure procedures.
Reading it isn't the same as speaking it
CAP 413 tells you what correct sounds like — but the FRTOL practical tests whether you can produce it, promptly and under mild pressure, with an examiner listening. That's a speaking skill: most candidates who struggle don't lack knowledge, they lack reps. The fastest route is short, frequent spoken practice with feedback that points at the standard — which is exactly what TowerTalk does: practise calls graded against CAP 413, or work through the CAP 413 revision path first.
Where to get the manual
Download the current edition free from the CAA at caa.co.uk/cap413. Always defer to the current CAA publication — TowerTalk is a practice aid built around the standard, not a substitute for it.
CAP 413 FAQs
What is CAP 413?
CAP 413 is the UK Civil Aviation Authority's Radiotelephony Manual — the reference for how radio communication is conducted in UK airspace. It sets out the standard words, phrases, message formats and procedures that pilots, controllers and ground operators are expected to use.
Is CAP 413 free?
Yes. The CAA publishes CAP 413 free of charge on caa.co.uk. Printed copies are sold by third-party pilot shops, but the PDF costs nothing.
Do I need to memorise CAP 413 for the FRTOL?
No — you need to reliably produce the standard phraseology for the situations a pilot actually meets: departures, en-route services, zone and MATZ crossings, circuit calls, and emergencies. That's a fluency skill built by speaking, not a memory test on the document.
Which edition of CAP 413 is current?
Edition 24 at the time of writing — but the CAA amends it periodically, so always take the current edition and amendment from caa.co.uk rather than a saved copy.