CAP 413, Manual

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CAP 413 Radiotelephony Manual
Chapter 1 Page 5
Straight Ahead When used in departure clearances means: ‘track extended
runway centre-line’. When given in Missed Approach Procedures means: ‘continue
on Final Approach Track’.
Terminal Control Area A control area normally established at the confluence of
airways in the vicinity of one or more major aerodromes (ICAO).
Threshold The beginning of that portion of the runway useable for landing (ICAO).
Traffic Alert and Collision Avoidance System (TCAS) See Airborne Collision
Avoidance System (ACAS).
Traffic Service A Traffic Service is a surveillance ATS, where in addition to the
provisions of a Basic Service, the controller provides specific surveillance derived
traffic information to assist the pilot in avoiding other traffic. Controllers may provide
headings and/or levels for the purposes of positioning and/or sequencing; however,
the controller is not required to achieve deconfliction minima, and the avoidance of
other traffic is ultimately the pilot’s responsibility.
Vectoring Provision of navigational guidance to aircraft in the form of specific
headings, based on the use of an ATS surveillance system (ICAO).
VFR Flight A flight conducted in accordance with the visual flight rules (RoA).
Visual Meteorological Conditions (VMC) Weather permitting flight in accordance
with the Visual Flight Rules (ANO).
1.2 Abbreviations
1.2.1 The following abbreviations are those in common use in the United Kingdom. If RTF
transmission of an abbreviation is required, and the format is not specified in this
document, the format specified by ICAO (see ICAO PANS-ABC Doc. 8400) should be
used. If no format is defined, the abbreviation should be described using the phonetic
alphabet.
1.2.2 The abbreviations annotated with an asterisk are normally spoken as complete words.
The remainder are normally spoken using the constituent letters rather than the
spelling alphabet. Military abbreviations are marked with '(M)'.
A
AAIB Air Accident Investigation Branch
aal Above Aerodrome Level
ACAS* Airborne Collision Avoidance System (pronounced A-kas) (see TCAS)
ACC Area Control Centre
ADF Automatic Direction-Finding Equipment
ADR Advisory Route
ADT Approved Departure Time
AEF Air Experience Flight (M)
AFTN Aeronautical Fixed Telecommunication Network
AFIS Aerodrome Flight Information Service
AGCS Air Ground Communication Service
agl Above Ground Level
31 March 2011