How TowerTalk grades a radio call
Every transmission you make is marked against a written rule, and every rule names the document, edition and paragraph it was read from. This page is the whole list. It is generated from the same data the grader uses, so it cannot describe something the grader does not do.
What “graded against CAP 413” actually means here
It does not mean a script comparison. Your call is checked for the things a rule requires: whether the mandatory items were read back in full, whether your callsign was included, whether the words used were the standard ones, and whether the order made sense to the controller receiving it.
Each rule below was extracted from the printed document, checked against it by hand, and only then switched on. An unchecked extraction cannot reach you, the grader or this page — there is one gate and everything passes through it. That is why the count here is smaller than the manual is long.
We do not reproduce CAP 413. The rules are stated in our own words with the paragraph given, so you can look it up and hold us to it.
66 rules currently in force, across 4 documents. Last reviewed 11 September 2026.
CAP 413 Radiotelephony Manual
Edition 24 (amendments to 31 March 2026)
The CAA's Radiotelephony Manual. The phraseology standard the FRTOL is assessed against, and the document an examiner marks from.
§2.69
These ATS messages are to be read back IN FULL: (1) taxi/towing instructions; (2) level instructions; (3) heading instructions; (4) speed instructions; (5) airways or route clearances; (6) approach clearances; (7) runway-in-use; (8) clearance to enter, land on, take off on, backtrack, cross or hold short of any active runway; (9) SSR operating instructions; (10) altimeter settings, including the units when the value is below 1000 hectopascals; (11) VDF information; (12) frequency changes; (13) type of ATS service; (14) transition levels. Items NOT on this list may be acknowledged with an abbreviated read-back (§2.70).
Why: §2.68: the stringency of the read-back requirement is directly related to how serious a misunderstanding would be.
CAP 413 Radiotelephony Manual Edition 24 (amendments to 31 March 2026) §2.69
§2.68
ATC route clearances shall ALWAYS be read back unless the ATS authority has authorised otherwise, in which case they are acknowledged positively. Read-backs shall always include the aircraft callsign.
On frequency
- “After departure cleared to zone boundary via route Echo. Climb to altitude 2000 feet QNH 1008, squawk 6522, G-ABCD”
CAP 413 Radiotelephony Manual Edition 24 (amendments to 31 March 2026) §2.68
§2.71
If a pilot's read-back of a clearance or instruction is incorrect, the controller shall transmit the word NEGATIVE followed by the correct version.
On frequency
- “Negative, G-ABCD, climb altitude 3000 feet”
CAP 413 Radiotelephony Manual Edition 24 (amendments to 31 March 2026) §2.71
§2.69
If a read-back is not received, the pilot/driver will be instructed to provide one. Equally, a pilot is expected to ask for an instruction to be repeated or clarified if any part of it is not fully understood.
CAP 413 Radiotelephony Manual Edition 24 (amendments to 31 March 2026) §2.69
§4.33
A conditional instruction is given in FIVE parts, in order: (1) callsign, (2) the condition, (3) identification of the subject of the condition, (4) the clearance, (5) REITERATION of the condition. It relates to one movement only and, for landing traffic, must be the first aircraft on approach. Conditional phrases are not used for movements affecting an active runway unless both controller and pilot can see the traffic concerned.
On frequency
- “BIGJET 347, behind the landing DC9, line up Runway 26 behind”
- “G-CD, behind the landing PA28, cross runway 28 behind, report vacated”
Why: The fifth element is the point: the instruction opens AND closes with the condition, so a pilot who hears only the tail of the transmission still hears 'behind'. CAP 493 §14.3 names conditional clearances as a significant contributory factor in runway incursions.
CAP 413 Radiotelephony Manual Edition 24 (amendments to 31 March 2026) §4.33 · differs from ICAO
Supplement to CAP 413 (UK Phraseology for CAT Pilots)
© 2007 (no edition number printed)
The supplement to CAP 413. Quoted for the reasoning behind a rule, where the manual states one.
§3 Climb-Cruise-Descent › Flight Levels
Flight levels of whole hundreds are transmitted as 'flight level one hundred', 'two hundred' etc. The ICAO form 'flight level one zero zero' is NOT used in the UK.
On frequency
- “climb flight level one hundred”
Why: Mitigation against level busts.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Flight Levels · differs from ICAO
§3 Climb-Cruise-Descent › Flight Levels
Flight levels below FL100 are spoken as two digits, e.g. 'flight level eight zero'.
On frequency
- “climb flight level eight zero”
Why: Reduces the risk of confusion with a heading instruction (e.g. 'heading zero eight zero').
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Flight Levels · differs from ICAO
§3 Climb-Cruise-Descent › Degrees
'Degrees' is appended to any heading ending in zero, to prevent headings being confused with flight levels.
On frequency
- “fly heading two six zero degrees”
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Degrees · differs from ICAO
§3 Climb-Cruise-Descent › To (UK Only)
The word 'to' is not used when issuing climb/descent instructions to a FLIGHT LEVEL — it can be confused with the number 'two'. 'To' IS used for a height or altitude, and is followed by the word 'height' or 'altitude'.
On frequency
- “climb flight level one two zero”
- “descend to altitude three thousand feet”
Why: This confusion has resulted in level busts.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › To (UK Only) · differs from ICAO
§3 Climb-Cruise-Descent › 'Pass Your Message' (UK Only)
In the UK, 'Go Ahead' is replaced by 'Pass your message'.
On frequency
- “pass your message”
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › 'Pass Your Message' (UK Only) · differs from ICAO
§4 Approach and Landing › ILS Phraseology (UK only)
'Cleared ILS approach' is not routinely used in the UK. Radar controllers use 'Report established on the localiser', then clear the aircraft to 'Descend on the ILS'. In busy RTF these combine: 'When established on the localiser, descend on the ILS.'
On frequency
- “report established on the localiser”
- “descend on the ILS”
- “when established on the localiser, descend on the ILS”
Why: 'Cleared ILS approach' leaves it uncertain when descent begins — the pilot may descend to platform height at any time after receiving it. The UK phrasing ensures descent starts only when clear of other traffic patterns (helicopter routes, adjacent aerodrome procedures).
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §4 Approach and Landing › ILS Phraseology (UK only) · differs from ICAO
§2 Taxi and Take-off › Conditional Taxi Clearance
Read back a conditional clearance with the CONDITION FIRST, so the controller knows the pilot heard the condition the clearance rests on. Read back in full and in the same sequence as given.
On frequency
- “After the landing Little Jet Airbus 321, cross runway 09 at C2, Big Jet 345”
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §2 Taxi and Take-off › Conditional Taxi Clearance
§3 Climb-Cruise-Descent › Conditional Clearances in a TMA
Conditional clearances may be issued in the TMA (e.g. 'After passing altitude 4000 feet, fly heading…') and must be read back in exactly the format given.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Conditional Clearances in a TMA
§2 Taxi and Take-off › Take-off
In the airport environment the word 'cleared' is used ONLY for a clearance to take off or land. Other exchanges use words such as 'cross' and 'approved'. A take-off clearance is always issued separately.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §2 Taxi and Take-off › Take-off
§2 Taxi and Take-off › Take-off / Departure Delay Information
'After departure' and 'follow' are NOT take-off clearances. Departure sequence information such as 'number 5 to depart' or 'expect departure in…' is NOT a take-off clearance.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §2 Taxi and Take-off › Take-off / Departure Delay Information
§2 Taxi and Take-off › Amendment to Departure Clearance
Amendments to a departure clearance for an aircraft approaching the runway begin with 'hold position'. Revised departure instructions are prefixed with it, and 'after departure' is used when issuing airways/route clearances.
On frequency
- “Big Jet 345, hold position, amendment to clearance, T3F departure, climb to altitude 6000 feet”
Why: Amendments to departure clearances contribute to runway incursions.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §2 Taxi and Take-off › Amendment to Departure Clearance
§2 Taxi and Take-off › Taxi Clearance Limit
Every taxi clearance contains a clearance limit — the point at which the aircraft must stop unless given further permission. Crossing any runway, active or not, needs a specific crossing clearance.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §2 Taxi and Take-off › Taxi Clearance Limit
§2 Taxi and Take-off › Messages Containing The Following Must Be Read Back
Must be read back: taxi instructions; level instructions; heading instructions; speed instructions; airways/route clearances; approach clearances; runway in use; any runway clearance; SSR operating instructions; altimeter settings; VDF information; frequency changes; type of radar service; transition levels.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §2 Taxi and Take-off › Messages Containing The Following Must Be Read Back
§2 Taxi and Take-off › Read-back
Read back complete and in the order given — checking accuracy is far easier that way, and missing elements of an incomplete read-back are harder to detect than an outright error.
Why: The most common cause of a level bust in the UK is a CORRECT read-back followed by incorrect action. Note the clearance down before reading back; both crew should listen to all clearances.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §2 Taxi and Take-off › Read-back
§3 Climb-Cruise-Descent › Initial Calls
First contact after departure must include: callsign; SID; current or passing level (so Mode C can be verified) PLUS cleared level.
On frequency
- “Metro Radar, Big Jet 345, T3F, passing altitude 2300 feet climbing to altitude 6000 feet”
Why: Studies show an initial call missing required information can lead to a loss of separation; omissions force a clarifying call and congest the frequency.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Initial Calls
§3 Climb-Cruise-Descent › Initial Calls
On first contact with SUBSEQUENT frequencies: callsign, current level, cleared level (or if not in level flight, cleared level only), and any ATC-assigned speed or heading.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Initial Calls
§3 Climb-Cruise-Descent › RTF for TCAS
Report the direction of a TCAS RA to the controller as soon as practicable. Responsibility for separation transfers from controller to pilot for the manoeuvre, and back on completion.
On frequency
- “Big Jet 345, TCAS climb”
- “Big Jet 345, returning to (assigned clearance)”
- “Big Jet 345, TCAS climb, returning to (assigned clearance)”
- “Big Jet 345, TCAS climb completed, (assigned clearance) resumed”
- “Unable to comply, TCAS RA, Big Jet 345”
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › RTF for TCAS
§3 Climb-Cruise-Descent › Reduced Vertical Separation Minima
RVSM status is stated as 'Negative RVSM' or 'Affirm RVSM'. A refusal states the reason ('Unable RVSM due turbulence' / 'due equipment'). 'Ready to resume RVSM' when able. 'Negative RVSM' appears in both the clearance and the read-back.
On frequency
- “request flight level three two zero, negative RVSM”
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Reduced Vertical Separation Minima
§3 Climb-Cruise-Descent › Simultaneous or Continuous Transmissions
On hearing a simultaneous transmission, a pilot may transmit 'blocked' so the controller knows a transmission was stepped on.
On frequency
- “Transmission blocked, Big Jet 345”
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Simultaneous or Continuous Transmissions
§3 Climb-Cruise-Descent › Wake Vortex Separation
Do not request reduced wake vortex separation — controllers have no discretion to grant it.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Wake Vortex Separation
§3 Climb-Cruise-Descent › Descending in the Hold
Report leaving a level only once the altimeter shows the aircraft has actually left it and is maintaining a positive rate of climb/descent.
Why: Controllers may descend an aircraft above you as soon as you report vacating.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §3 Climb-Cruise-Descent › Descending in the Hold
§1 Push and Start › Top tips for avoiding communication error
Standard phraseology at all times; avoid unnecessary RTF; both pilots monitor the frequency where possible; never read back a clearance as a question — use 'say again'; pass all information relevant to the phase of flight; wait and listen before transmitting after a frequency change; state the condition first on a conditional clearance; check RTF after a prolonged silence; SET THE CLEARANCE GIVEN, NOT THE CLEARANCE EXPECTED; note ATC instructions down; if unsure, always check.
Why: Communication error is a significant contributory factor in both level busts and runway incursions in the UK.
Supplement to CAP 413 (UK Phraseology for CAT Pilots) © 2007 (no edition number printed) §1 Push and Start › Top tips for avoiding communication error
CAP 493 Manual of Air Traffic Services Pt 1
Edition 12 (31 October 2025)
The Manual of Air Traffic Services. What the controller on the other end is required to say, which is what makes an unscripted reply realistic rather than invented.
§2.1
In accordance with ICAO requirements, English shall be used for all radiotelephony communications.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §2.1
§5.1
Every endeavour is made to clear an aircraft by the route requested; where that is not possible the controller explains the reason when issuing the clearance. The expression 'cleared flight plan route' is NOT to be used for re-clearances (SERA.8015(d)(3)(ii)).
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §5.1
§5.2
If a pilot requests, or a controller offers, a direct routeing, the controller must tell the pilot if that route will take the aircraft outside the lateral or vertical boundaries of controlled or advisory airspace.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §5.2
§12.3
The phrase 'continue as cleared' is NOT to be used in response to an initial call from an aircraft.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §12.3
§13A.1–13A.2
Where a delay is not known, aircraft are advised 'delay not determined', and EATs are issued as soon as approach procedures can resume. 'Delay not determined' is NOT to be used when changing runways — delays there can be forecast with reasonable accuracy and EATs are to be passed.
On frequency
- “delay not determined”
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §13A.1–13A.2
§9A.1
In radiotelephony the term 'wake turbulence' is used to describe the effect.
On frequency
- “caution wake turbulence”
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §9A.1
§Sect 2 Ch 1, 14.4
The phrase "line up in turn" is ambiguous and misleading and is NOT to be used.
Why: CAP 493 §14.3 names conditional line-up clearances as a significant contributory factor in runway incursion incidents, and non-standard phrasing as what makes them worse.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 14.4
§Sect 2 Ch 1, 15.4
A take-off clearance shall be issued SEPARATELY from any other clearance message. If an aircraft is already lined up and a revised clearance or post-departure instruction must be passed, it shall be prefixed with an instruction to HOLD POSITION.
On frequency
- “hold position”
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 15.4
§Sect 2 Ch 1, 15.2
Unless MATS 2 states otherwise, a take-off clearance shall include the designator of the departure runway.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 15.2
§Sect 2 Ch 1, 16.1–16.2
To cancel a take-off clearance BEFORE the take-off run has begun, instruct the pilot to HOLD POSITION and to acknowledge. To cancel AFTER the run has begun, instruct the pilot to STOP IMMEDIATELY and to acknowledge.
On frequency
- “hold position”
- “stop immediately”
Why: §16.3–16.4: cancelling after the roll has started should only happen if continuing means serious and imminent danger — above ~80kt the risk of rejecting is itself significant, and the commander may judge it safer to continue.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 16.1–16.2
§Sect 2 Ch 1, 12.1–12.2
Every taxi clearance must contain a specific clearance limit. A clearance to a limit BEYOND a runway must contain an explicit clearance to cross that runway; otherwise the limit and route must stop short of it. "Hold short" may be used for emphasis — e.g. "taxi to holding point D2, hold short of runway 25R".
On frequency
- “hold short of runway 25R”
- “taxi to holding point D2”
Why: Clearing an aircraft to the holding point of the runway-in-use otherwise permits it to cross every runway intersecting that route, active or not.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 12.1–12.2
§Sect 2 Ch 1, 8.1–8.2
Essential aerodrome information — anything about the state of the manoeuvring area or its facilities that may be a hazard — shall be given to EVERY aircraft, in time to be used, unless it is known the aircraft already has it from ATIS, NOTAM or signals. It covers work in progress, rough or broken surfaces, and failure or irregular functioning of aerodrome lighting or approach aids.
Why: §8.2(3): defects are passed as reported. A controller must not assume a defect makes an aid unserviceable — deciding the course of action is the pilot's.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 8.1–8.2
§Sect 2 Ch 1, 6B
Controllers shall advise pilots of both the implementation AND the subsequent cancellation of Low Visibility Procedures at an aerodrome.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 6B
§Sect 2 Ch 1, 10C.4
A pilot who is lost or uncertain of their position on the manoeuvring area will stop and tell ATS, including their last known position. If they recognise they are ON a runway and a suitable taxiway is nearby, they should vacate as expeditiously as possible unless instructed otherwise, then stop. The controller shall issue instructions to eliminate or mitigate the hazard.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 10C.4
§Sect 2 Ch 1, 14.1
Line-up may be issued to more than one aircraft on the same or crossing runways ONLY if: it is daylight; all aircraft are continuously visible to the controller; all are on the same RTF frequency; pilots are told how many aircraft are ahead and from which position/runway they depart; and no preceding aircraft is hidden by the runway's physical characteristics.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 14.1
§Sect 2 Ch 1, 14.2
Where line-up is from a position other than full length, the intermediate holding position designator SHALL be included in the line-up instruction.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 2 Ch 1, 14.2
§Sect 1 Ch 6, 13A.2
Aircraft outside controlled airspace, and VFR flights in Class E, are NOT obliged to follow ATC instructions. Where a pilot has accepted a Traffic Service or Deconfliction Service, however, the controller may expect their instructions to be followed.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 1 Ch 6, 13A.2
§Sect 1 Ch 6, 13A.3
Unless it planned to leave, an aircraft is not to be vectored outside the horizontal or vertical limits of controlled airspace, except: (1) in an emergency; (2) to avoid severe weather, where the circumstances must be explained to the pilot BEFORE it leaves; or (3) when the pilot specifically requests it.
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 1 Ch 6, 13A.3
§Sect 1 Ch 6, 13A.5
When vectoring is complete, pilots are to be instructed to RESUME OWN NAVIGATION. Where a direct route is required, the controller shall specify it in that instruction.
On frequency
- “resume own navigation”
CAP 493 Manual of Air Traffic Services Pt 1 Edition 12 (31 October 2025) §Sect 1 Ch 6, 13A.5
UK AIP ENR 1.1 (UK Flight Information Services)
AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26)
The UK Aeronautical Information Publication. Where the flight information services and their limits are defined.
§2.2.1
In Class G, REGARDLESS of the service being provided, the pilot is ultimately responsible for collision avoidance and terrain clearance.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.2.1
§2.2.2
The PILOT determines the appropriate service and requests it. Deconfliction Service and Procedural Service are IFR-only, irrespective of met conditions. An Alerting Service accompanies all services.
On frequency
- “request Basic Service”
- “request Traffic Service”
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.2.2
§2.2.3
FISOs are NOT licensed to provide a Traffic Service, Deconfliction Service or Procedural Service — Basic Service only. Controllers make all reasonable endeavours to provide the requested service, but workload and finite resources may constrain availability.
Why: Directly constrains the AFIS persona: it must decline or redirect a request for anything beyond a Basic Service, never simply provide it.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.2.3
§2.2.4
Instructions issued to pilots operating OUTSIDE controlled airspace are not mandatory; the services depend on pilot compliance with their terms.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.2.4
§2.2.5
A controller and pilot may agree a lateral or vertical restriction beyond the core terms of a Basic or Traffic Service. Unless safety would be compromised, a pilot shall not deviate from an agreement without first advising the controller AND obtaining a response.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.2.5
§2.2.6
Where traffic information will be reduced (workload, traffic density, unknown high-energy traffic, surveillance clutter), the controller SHALL inform the pilot of the reduction, the reason and its probable duration — though not always in a timely fashion.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.2.6
§2.3.1–2.3.5
Basic Service is advice and information useful for the safe and efficient conduct of a flight — weather, serviceability changes, aerodrome conditions, general airspace activity. Avoidance of other traffic is SOLELY the pilot's responsibility. Available IFR outside CAS in any met conditions, or VFR, at all levels; the pilot remains responsible for terrain clearance.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.3.1–2.3.5
§2.3.3
Under a Basic Service a pilot should NOT expect traffic information. Where the controller/FISO knows of activity that may affect the flight they should pass it in GENERAL TERMS for situational awareness — normally without updating it unless the situation changes markedly or the pilot asks.
Why: Key persona constraint: a Basic Service station giving running, specific traffic updates is behaving like a Traffic Service and is wrong.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.3.3
§2.3.5
Under a Basic Service, unless an agreement is in place, the pilot may change heading, route or level WITHOUT advising the controller. A controller will NOT issue specific heading instructions; generic navigational assistance may be given on request.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.3.5
§2.4.1–2.4.5
Traffic Service is surveillance-based: Basic Service plus SPECIFIC surveillance-derived traffic information to help the pilot avoid other traffic. Avoidance remains solely the pilot's responsibility. Available IFR outside CAS in any met conditions, or VFR. The controller may provide headings/levels for positioning, sequencing or navigational assistance.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.4.1–2.4.5
§2.4.2
If a controller issues a heading and/or level that would require flight in IMC, a pilot not qualified for IMC shall say so and request alternative instructions.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.4.2
§2.4.3
Under a Traffic Service in Class G, a pilot who wants deconfliction advice must REQUEST AN UPGRADE to Deconfliction Service. Deconfliction Service is not available in Class E.
On frequency
- “request upgrade to Deconfliction Service”
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.4.3
§2.4.6–2.4.7
Under own navigation a pilot may alter course as required, but shall not change general route or manoeuvring area without first advising the controller and obtaining a response. On an ATC heading or allocated level, a pilot shall not change heading, level or level band without first advising and obtaining a response.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.4.6–2.4.7
§2.5.1–2.5.6
Deconfliction Service is surveillance-based: Basic Service plus specific traffic information AND deconfliction advice (a heading and/or level aimed at a planned deconfliction minima). IFR-only, in Class G, irrespective of met conditions. Controllers cannot guarantee the minima but shall apply all reasonable endeavours; avoidance is ultimately the pilot's responsibility.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.5.1–2.5.6
§2.5.4
A pilot who elects NOT to act on deconfliction advice shall inform the controller, and thereby accepts responsibility for collision avoidance against that conflicting aircraft.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.5.4
§2.5.5
Deconfliction Service is only provided at or above a terrain-safe level — except when departing and climbing to one, or following notified instrument approach procedures, where traffic information WITHOUT deconfliction advice is passed instead (unless the pilot requests advice or the controller judges a definite collision risk).
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.5.5
§2.5.6
Under a Deconfliction Service, unless safety would be compromised, a pilot shall not change heading or level without first obtaining APPROVAL (not merely advising) from the controller.
Why: Note the escalation across services: Basic — no need to advise; Traffic — advise and get a response; Deconfliction — obtain approval.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.5.6
§2.6.1–2.6.6
Procedural Service is NON-surveillance: Basic Service plus instructions which, if complied with, achieve deconfliction minima against other aircraft ALSO receiving a Procedural Service. Neither traffic information nor deconfliction advice can be passed about unknown traffic. IFR-only, available at all levels; the pilot is wholly responsible for terrain clearance.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.6.1–2.6.6
§2.6.4
Deconfliction under a Procedural Service is achieved by allocating levels, radials, tracks, routes, time restrictions, approach clearances and holding instructions, or by using pilot position reports.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.6.4
§2.6.6
Under a Procedural Service, unless safety would be compromised, a pilot shall not change level, radial, track, route or time restriction without first obtaining approval. If any is unacceptable, the pilot shall say so immediately.
UK AIP ENR 1.1 (UK Flight Information Services) AIRAC 07/2026, effective 2026-07-09 (eAIP package AIRAC-07-26) §2.6.6
What this page is not
- It is not a copy of CAP 413. Buy or download the manual from the CAA and read the paragraph yourself — that is the point of citing it.
- It is not the whole of CAP 413. Rules arrive here as they are checked, and the list grows.
- It is not instruction. TowerTalk is a training aid; your instructor and your examiner are the authority on whether you are ready.
Practise this at your airfield
Reading the rule is the easy half. Pick your own airfield, with its real frequencies and today’s weather, and say the calls out loud until the rules stop being things you remember and start being things you do.
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