The following Glossary is centric to Flight Simulation Training Devices (FSTDs) and although many terms and abbreviations have similar, or the same meaning in other parts of the aviation industry, the following is specific to FSTDs.  The list has been created from many sources plus the valued input of the colleagues of Training Technology International (Canada) Ltd.  Every effort has been made to make sure it is accurate, but as with all documents of this type it is quite possible that errors exist.  If you find one of those, or have a suggestion for improvement, please contact us here…

Approved Training Organisation

An Approved Training Organisation (ATO) is an organisation staffed, equipped and operated in a suitable environment offering approved flying training, and/or synthetic flight instruction and/or theoretical knowledge instruction for specific flight training programmes (aeroplane or helicopter).

ATS Route

ATS Route is a specified route designed for channeling the flow of traffic as necessary for the provision of air traffic services. The ATS Route can contain more than just navigation data and is provided as a vector geospatial enabled file format.

Audited engineering simulation

‘Audited engineering simulation’ means an aircraft manufacturer’s engineering simulation that has undergone a review by the appropriate competent authorities and been found to be an acceptable source of supplemental validation data.

Authority Requirements for Aircrew

EASA Authority Requirements for Aircrew (Part-ARA). Part-ARA means Annex VI to the Regulation on Civil Aviation Aircrew

Automatic Direction Finder

An automatic direction finder is a radio-navigation instrument that automatically and continuously displays the relative bearing from the aircraft to a suitable radio station. ADF receivers are normally tuned to aviation or marine NDBs operating in the LW band between 190 – 535 kHz.

Automatic Flight Control System

A system which includes all equipment to control automatically the flight of an aircraft or missile to a path or attitude described by references internal or external to the aircraft or missile. Used to be referred to as the ‘Auto Pilot’

Automatic testing

‘Automatic testing’ means flight simulation training device (FSTD) testing wherein all necessary stimuli are under computer control.

Bank / Bank Angle
BANK or Phi

‘Bank’ means bank/roll angle (degrees) the airplane attitude with respect to or around the longitudinal axis.


‘Baseline’ means a fully flight test validated production aircraft simulation. It may represent a new aircraft type or a major derivative. It may also refer to the status of any system before update.

Basic Instrument Training Device

‘Basic instrument training device (BITD)’ means a ground-based training device which represents the student pilot’s station of a class of aeroplanes. It may use screen based instrument panels and spring loaded flight controls, providing a training platform for at least the procedural aspects of instrument flight.

Basic Operating Weight 

The empty weight of the aircraft plus the weight of the following: Normal oil quantity; lavatory servicing fluid; potable water; required crewmembers and their baggage; and emergency equipment. 

Batch Testing

The process of setting up a QTG utility to conduct a series of validation tests sequentially generally under computer control and without manual intervention.

BITD Manufacturer

‘BITD manufacturer’ means that organisation or enterprise being directly responsible to the competent authority for requesting the initial BITD model qualification.

BITD Model

‘BITD model’ means a defined hardware and software combination, which has obtained a qualification. Each BITD will equate to a specific model and be a serial numbered unit.


‘Breakout’ means the force required at the pilot’s primary controls to achieve initial movement of the control position.

Calibrated airspeed

Calibrated airspeed is indicated airspeed corrected for instrument and position error. When flying at sea level under International Standard Atmosphere conditions calibrated airspeed is the same as equivalent airspeed and true airspeed. If there is no wind it is also the same as ground speed.


A measurement of brightness. 3.4263 candela/m/m = 1 ft-Lambert. The candela is the base unit of luminous intensity in the International System of Units; that is, luminous power per unit solid angle emitted by a point light source in a particular direction. Usually used to check visual system brightness.

Centimeter, centimetre. 

A metric/SI unit of linear measurement. 1cm = 0.39370079 in

Centre of Gravity

The center of gravity (C.G.) of an aircraft is the point in its structure over which the aircraft would balance in all axis. As the longitudinal C of G changes with fuel burn etc., it is usually defined as a % MAC (Mean Aircraft Chord)

Certificate Holder

In FAA terminology, a person or organization issued a certificate under parts 119, 141, or 142 or a person holding an approved course of training for flight engineers in accordance with part 63.