Residents interested in understanding aircraft operations are often confronted by a barrage of complicated and technical aviation terms. It can soon become very confusing. For example, is there a difference between ‘flight path’ and ‘flight track’?

To further confuse the situation, agencies responding to residents’ complaints or enquiries can inadvertently use the wrong word or term as they try to explain the concepts of air traffic management without the use of technical jargon.

This document sets out some of the more common words and phrases used in explaining aircraft operations together with a brief definition or explanation.  The intent is not to provide a technical aviation definition, but rather a definition for non-aviation residents to understand.

Aviation word/term

CDA (or CDO)
Continuous Descent Approach. Also known as Continuous Descent Operations (CDO). Subject to airspace design and use, and in ideal conditions, allows an aircraft to practically glide to an airport with engines at idle power. This results in lower noise levels compared to traditional approach paths that have intermediate altitudes where an aircraft will level off.

Circuits
Usually refers to aircraft that are taking off, flying in a rectangular type pattern and landing again as part of their operational training.

Controlled airspace
Airspace that is managed by air traffic controller (ATC). Not all airspace is under the control of ATC, but near major airports and in busy flight path areas, airspace in Australia is controlled.

Curfew
Legislated procedures at an airport to restrict the types of aircraft and the way they can operate at an airport overnight. Four airports in Australia have a curfew – Sydney, Adelaide, Gold Coast and Essendon.

Fixed wing aircraft
Any aircraft other than helicopters. Helicopters are referred to as ‘rotary wing’ aircraft.

Flight corridor
A term commonly used to describe a grouping of  flight tracks taken by aircraft.

Flight path
A single path depicting where an aircraft intends to fly.

Flight plan
A broad explanation of a flight from one point to another. For example, a Sydney to Melbourne aircraft might plan via Wollongong, Canberra and Eildon Weir.

Flight track
A line on a map showing exactly where an aircraft actually flew.

Fly Neighbourly Agreement or Fly Friendly Agreement
Voluntary procedures adopted by pilots to minimise the effect of aircraft noise at an airport.

GBAS
Ground Based Augmentation System – see SmartPath definition.

General aviation
A term used to describe the many small aircraft operating in Australia that are not generally used by airlines or large charter companies.

Glide path
Usually refers to the final slope path to a runway emitted by a ground based navigation aid (Instrument Landing System). Equates to approximately a three degree descent angle.

Ground running
Aircraft running engines or auxiliary power units while on the ground. May be running for maintenance, to provide power or engine testing.

HIAL
High Intensity Approach Lights – a series of very strong lights in line with a runway, and close to the touch-down point, to assist a pilot landing in poor weather conditions.ILSAn Instrument Landing System (ILS) is a ground based navigation system which provides horizontal and vertical guidance necessary for a precision landing approach.JetA fixed wing aircraft (not helicopter) powered by jet engines rather than propellers.

Missed approach
A standard procedure when an aircraft descending to arrive at an airport decides not to land and commences to climb.  May occur for training, due to an obstructed runway, engineering issue or bad weather.Navigation aidsGround equipment that radiates signals for aircraft to use to assist in navigation.

Noise abatement procedures
Procedures followed by air traffic controllers or pilots to reduce the effects of noise experienced on the ground.  Noise abatement procedures are not applicable when safety or operational requirements mean that other procedures need to be followed.

Noise monitor
Either a permanent or temporary piece of equipment used to record the noise generated on the ground by a passing aircraft.

Propeller aircraft
There are two types of propeller aircraft. Generally the simple, smaller engines are piston powered, using fuel igniting in a chamber to drive a piston up and down and turn the propeller. The other type uses a turbine powered propeller which uses a rotating disc with blades to create high air pressure before ignition. Most of the larger propeller aircraft are turbine powered and referred to as turboprops.

RNP
Required Navigation Performance – see Smart Tracking definition.

Rotary wing aircraft
Any powered aircraft other than fixed wing aircraft.

Smart Tracking
A satellite assisted navigation system used by a growing number of modern aircraft. Allows an aircraft to fly extremely accurately and also has the capacity for curved arrival paths. Known in aviation circles as RNP – Required Navigation Performance.

SmartPath
Uses a combination of satellite signals and ground signals to provide final approach paths to an airport. Can be used in place of an ILS. Also known as GBAS – Ground Based Augmentation System.

Turboprop
One of two types of propeller aircraft. A turboprop uses a jet turbine engine to power the propeller.Most of the larger propeller aircraft in Australia are turbine powered and referred to as turboprops.

Uncontrolled airspace
Airspace not managed by air traffic controllers. Procedures apply in this airspace to provide appropriate levels of aviation safety, as set out by the Civil Aviation Regulations.