Glossary

Just like every industry, the drone industry comes with a lot of acronyms. This glossary breaks down the terms you'll come across when flying, from regulatory approvals like BVLOS and RePL through to the payloads and data outputs behind every mission.

ADS-B

or

Automatic Dependent Surveillance Broadcast

A system where an aircraft broadcasts its position so others can see and avoid it, increasingly relevant to drones sharing airspace.

Operator accreditation

or

RPA operator accreditation

A short online CASA credential that lets you fly a drone commercially in the excluded category without a full Remote Pilot Licence.

AAM

or

Advanced Air Mobility

An emerging field covering new aircraft like drones and air taxis and how they fit into shared airspace.

Chief Remote Pilot

or

CRP

The person a ReOC holder names as responsible for the safety and conduct of its drone operations.

AROC

or

Aeronautical Radio Operator Certificate

An aviation certificate covering the correct use of aeronautical radio, sometimes needed for operations that involve radio calls.

MTOW

or

Maximum Take-Off Weight

The heaviest a drone can safely weigh ready to fly. CASA uses weight thresholds to decide which rules and approvals apply.

Excluded category

A class of lower-risk commercial drone flights that can be flown on operator accreditation alone, without a ReOC, as long as standard conditions are met.

Standard Operating Conditions

or

SOC

The default safety limits for flying a drone, such as daytime only, within sight, below 120 m, and clear of people. Operating outside them needs approval.

Part 101

The section of CASR that sets the rules for drones and other remotely piloted aircraft in Australia.

CASR

or

Civil Aviation Safety Regulations

The rulebook for Australian aviation. Drone operations sit under its Part 101.

ARN

or

Aviation Reference Number

A unique number CASA assigns to a person or organisation in aviation. You need one to register a drone or apply for a licence.

OCTA

or

Outside Controlled Airspace

Airspace that sits outside air traffic control. CASA's BVLOS OCTA exam (ReB1) is the drone-specific alternative to the IREX for flying beyond line of sight there.

IREX

or

Instrument Rating Exam

A CASA aviation theory exam, first designed for crewed pilots, that a remote pilot can pass to fly BVLOS in controlled airspace.

Point cloud

A dense set of 3D points captured by LiDAR or photogrammetry that together form a measurable model of a site or object.

Orthomosaic

A single, distortion-corrected image built by stitching many aerial photos together so distances and areas can be measured accurately.

GSD

or

Ground Sample Distance

The real-world distance each pixel covers in an aerial image. A smaller GSD means finer detail in the final map.

NDT

or

Non-Destructive Testing

Techniques for checking the condition of a structure or material without damaging it, such as ultrasonic or visual testing.

UT

or

Ultrasonic Testing

An inspection method that uses high-frequency sound to measure material thickness and find hidden flaws.

Tethered drone

A drone connected to the ground by a cable that supplies continuous power and a secure data link for long stationary flights.

GPR

or

Ground Penetrating Radar

A sensor that sends radar pulses into the ground to detect buried objects, utilities, or changes below the surface.

Multispectral

or

Multispectral imaging

Imaging across several bands of light beyond what the eye can see, widely used to assess crop and vegetation health.

Thermal

or

Thermal imaging

Imaging that maps heat rather than light, used to spot temperature differences in equipment, ground, or people.

RGB

or

Red Green Blue

A standard colour camera that captures a scene the way the human eye sees it, in red, green, and blue.

Payload

The sensor or equipment a drone carries to do its job, such as a camera, LiDAR unit, or gas sensor.

AAUS

or

Australian Association for Uncrewed Systems

The peak industry body for drones and uncrewed systems in Australia, supporting safe and professional operations.

BARS

or

Basic Aviation Risk Standard

An international aviation safety standard, run by the Flight Safety Foundation, that audits operators against rigorous risk controls.

AVLOS

or

Assisted Visual Line of Sight

A pathway that lets a pilot fly with help from trained spotters rather than keeping the aircraft in their own direct sight the whole time.

SORA

or

Specific Operations Risk Assessment

A structured way to assess the air and ground risk of a complex drone operation, used by CASA to decide whether it can go ahead.

TMI

or

Temporary Management Instruction

A time-limited instruction CASA issues to set rules for a specific type of operation, such as the Broad Area BVLOS trial under TMI 2025-03.

UAS

or

Unmanned Aerial System

The whole package, meaning the aircraft plus the controller, software, and ground equipment that operate it together.

UAV

or

Unmanned Aerial Vehicle

An aircraft flown with no pilot on board, controlled remotely or autonomously. Often used interchangeably with drone and RPA.

Photogrammetry

Turning overlapping aerial photos into measurable maps and 3D models of a site.

RTK

or

Real-Time Kinematic

A positioning method that corrects satellite data live to place the drone within centimetres of true position.

LiDAR

or

Light Detection and Ranging

A sensor that fires laser pulses to build precise 3D measurements of terrain or structures.

Geofence

A virtual boundary in the flight software that stops a drone entering or leaving a defined area.

RTH

or

Return to Home

A function that flies the drone back to its launch point automatically if the link drops or the battery runs low.

GCS

or

Ground Control Station

The hardware and software a pilot uses on the ground to command the drone and view its feed.

AGL

or

Above Ground Level

A height measured from the ground directly below the aircraft rather than from sea level.

DiaB

or

Drone-in-a-Box

A drone housed in a self-contained ground station that can launch and recharge on its own, often with no one on site.

RPAS

or

Remotely Piloted Aircraft System

The complete system, meaning the aircraft together with the ground equipment used to control it.

RPA

or

Remotely Piloted Aircraft

The aircraft itself, flown from the ground with no pilot on board.

CASA

or

Civil Aviation Safety Authority

The body that regulates all aviation in Australia, including commercial drone operations.

ReOC

or

Remote Operator's Certificate

CASA approval that lets a business run commercial drone operations under its own set of conditions.

RePL

or

Remote Pilot Licence

The CASA credential a pilot holds to fly drones commercially beyond the excluded-category limits.

EVLOS

or

Extended Visual Line of Sight

The drone stays in sight using trained observers along the flight path rather than the pilot alone.

VLOS

or

Visual Line of Sight

The standard mode where the pilot keeps the drone within unaided sight for the whole flight.

BVLOS

or

Beyond Visual Line of Sight

Operating a drone past the distance a pilot can see it without visual aids. Needs specific CASA approval and unlocks longer-range missions.