Definitions — Page 16, Lesson 21

Let's start with the very first definition, because it sets the tone for everything else in this book: the Appropriate ATS Authority. ATS stands for Air Traffic Services. So the Appropriate ATS Authority is the relevant authority designated by the State responsible for providing air traffic services in the airspace concerned. In plain language: every piece of airspace belongs to some State, and that State is responsible for the air traffic services in it. The authority that State designates to do that job is the Appropriate ATS Authority for that airspace. Now, right after that comes a closely related term, and this one is easy to confuse with the first, so listen carefully: the Appropriate Authority. Notice it's not "Appropriate ATS Authority" — it's just "Appropriate Authority." This one is about who has jurisdiction over an aircraft, and it splits into two cases. First case: flight over the high seas. The high seas are international waters, no State has sovereignty there. So the Appropriate Authority is the relevant authority of the State of Registry — that is, the State where the aircraft is registered. Second case: flight other than over the high seas. That means flying over any territory that belongs to a State. Then the Appropriate Authority is the relevant authority of the State having sovereignty over the territory being overflown. So if you're flying over France, the French authority is the Appropriate Authority for that flight. So the key contrast here: the Appropriate ATS Authority is about who provides the air traffic service in a given airspace. The Appropriate Authority is about which State has jurisdiction over the aircraft — registry for the high seas, sovereignty of the territory overflown otherwise. Next, the Apron. This is a defined area, on a land aerodrome, intended to accommodate aircraft for the purposes of loading or unloading passengers, mail or cargo, fuelling, parking or maintenance. So it's the paved area where the aircraft sits when it's not on the runway or taxiway — where passengers board and disembark, where fuel trucks come, where the aircraft parks. Then we have the Area Control Centre, often abbreviated ACC. It's an air traffic control unit established to provide an area control service to aircraft flying within a notified flight information region — which are not receiving an aerodrome control service or an approach control service. So think of it as the controller who handles aircraft en route, in the wider airspace, not the ones taking off, landing, or in the immediate terminal area. And that leads to the Area Control Service. This is the air traffic control service for controlled flights in control areas. So the Area Control Centre provides the Area Control Service, and that service applies to controlled flights operating within control areas. Next, Area Navigation Equipment, abbreviated RNAV. This is equipment carried on board an aircraft which enables the aircraft to navigate on any desired flight path — within the coverage of appropriate ground based navigation aids, or within the limits of that on-board equipment, or a combination of the two. So instead of flying directly from one ground beacon to the next, RNAV lets the aircraft fly any path you want, as long as it's within the coverage of the ground aids, or within the capability of the onboard equipment, or both. Then we have the ATS Route. This is a specified route designed for channelling the flow of traffic as necessary for the provision of air traffic services. And there's an important note here: the term "ATS route" is used to mean variously — airway, advisory route, controlled or uncontrolled route, arrival or departure route, etc. So it's a general umbrella term covering many specific route types. Next, the Authorized Person. This definition has a list. An Authorized Person means: any constable; any person authorized by the Secretary of State — whether by name, or by class or description — either generally or in relation to a particular case or class of cases; and any person authorized by the Authority — again, whether by name or class or description, either generally or in relation to a particular case or class of cases. So this is about who has legal authority to act in certain enforcement or inspection roles. Then the Cabin Attendant. In relation to an aircraft, this means a person on a flight for the purpose of public transport, carried for the purpose of performing — in the interests of the safety of passengers — duties to be assigned by the operator or the commander of the aircraft. But — and this is a critical limitation — that person shall not act as a member of the flight crew. So the cabin attendant is there for passenger safety, assigned duties by the operator or commander, and is never part of the flight crew. Next, Captive Flight. This means flight by an uncontrollable balloon during which it is attached to the surface by a restraining device. So it's a balloon that can't be steered, and it's tethered to the ground. Then Cargo — and this is a simple but important one — cargo includes mail and animals. So whenever you see "cargo" in the regulations, remember it's not just freight; it covers mail and animals too. Next, Certified for Single-pilot Operation. This means an aircraft which is not required to carry more than one pilot. So if the aircraft's certification says one pilot is sufficient, it's certified for single-pilot operation. And finally, the Change-over Point. This is the point at which an aircraft navigating on an ATS route segment — defined by reference to very high frequency omni-directional radio ranges, abbreviated VOR — is expected to transfer its primary navigational reference from the facility behind the aircraft to the next facility ahead of the aircraft. And they are normally every 60 NM. So as you fly along a route defined by VOR beacons, at the change-over point you switch from navigating on the beacon behind you to the one ahead of you. These points are typically spaced 60 nautical miles apart. That's the full set of definitions in this opening section. We've covered the authorities, the aerodrome areas, the control services, the navigation equipment and routes, the personnel, the balloon flight, the cargo, the single-pilot certification, and the VOR change-over point.