A32X Aircraft Systems - Surveillance

Vocabulary practice flashcards covering aircraft surveillance systems including ATC Transponders, Weather Radar, GPWS/TAWS, ROPS, and TCAS.

Elementary Surveillance (ELS) and Enhanced Surveillance (EHS)

Transponder capabilities that allow Mode S ATC transponders to automatically respond to ATC and TCAS interrogations by transmitting flight data including aircraft address, altitude, flight number, airspeed, Mach number, heading, and selected altitude.

ADS-B OUT

A surveillance capability where Mode S transponders automatically and continuously broadcast position, altitude, track, velocity, flight number, and system integrity data to ATC ground stations and ADS-B IN equipped aircraft without prior interrogation.

ATC MODE - AUTO

The transponder operating mode where Mode S continuously transmits data and replies to interrogations in flight; on the ground, Modes A and C are inhibited while Mode S and ADS-B remain operative.

ATC MODE - STBY

The transponder operating mode in which the selected transponder does not transmit or reply to ground stations or other aircraft, and TCAS operations are set to standby.

IDENT Function

A flight crew selectable control on the ATC/TCAS panel or RMP page that transmits a special identification pulse signal to ATC ground radar when in AUTO mode.

ALT RPTG

The Altitude Reporting selection on the ATC controls that toggles the transmission of barometric standard altitude data by the active transponder ON or OFF.

Autotilt Function

A weather radar feature that uses the EGPWS terrain database to automatically adjust the antenna tilt based on aircraft position, altitude, and selected ND range to optimize weather detection and minimize ground clutter.

ON PATH Envelope

A vertical envelope bounded at $±4\,000\text{ ft}$ relative to the reference flight path along which the weather radar assesses whether detected weather returns directly threaten the aircraft trajectory.

Predictive Windshear System (PWS)

A weather radar safety system operating below $1\,800\text{ ft}$ or $2\,300\text{ ft}$ AGL that scans the airspace up to $5\text{ NM}$ ahead of the aircraft for microbursts and windshear hazards, issuing visual and aural warnings.

REACT (Rain Echo Attenuation Compensation Technique)

A weather radar feature that identifies and displays areas where severe precipitation attenuates radar signals and reduces target detection capability, indicated on the ND by magenta concentric arcs.

Predictive Lightning Icon

An intuitive ND symbol displayed by the Weather Hazard Prediction function in areas computed to have a high probability of lightning activity.

Predictive Hail Icon

An ICAO standard symbol displayed on the ND when the Weather Hazard Prediction function detects a high probability of hail threat within a convective cell.

Weather Ahead Function

A surveillance feature that monitors for red/yellow weather or turbulence $3\text{ min}$ ahead of the aircraft within a $2\text{ NM}$ lateral corridor and $±4\,000\text{ ft}$ vertical corridor, displaying an amber "WEATHER AHEAD" ND message.

Ground Proximity Warning System (GPWS)

An airborne safety system designed to prevent Controlled Flight Into Terrain (CFIT) using radio altitude radio modes (1 to 5) and database-driven terrain awareness functions (TAWS).

GPWS Mode 1

A basic GPWS mode providing aural ("SINK RATE", "PULL UP") and visual alerts for an excessive rate of descent.

GPWS Mode 2

A basic GPWS mode providing aural ("TERRAIN", "PULL UP") and visual alerts for an excessive terrain closure rate, separated into Mode 2A (climb/cruise) and Mode 2B (approach/takeoff).

GPWS Mode 3

A basic GPWS mode providing aural ("DON'T SINK") and visual warnings when significant altitude loss occurs during takeoff or go-around prior to reaching landing configuration.

GPWS Mode 4

A basic GPWS mode providing aural ("TOO LOW TERRAIN", "TOO LOW GEAR", "TOO LOW FLAPS") and visual alerts for unsafe terrain clearance when not in landing configuration.

GPWS Mode 5

A basic GPWS mode providing aural ("GLIDESLOPE") and visual warnings when the aircraft descends excessively below the ILS, SLS, or GLS glideslope path.

Terrain Awareness and Display (TAD)

A predictive GPWS mode that computes warning ($\sim 30\text{ s}$) and caution ($\sim 60\text{ s}$) terrain/obstacle conflict envelopes ahead of the aircraft, painting solid red or yellow risk areas on the ND.

Terrain Clearance Floor (TCF)

A predictive GPWS protection function that creates a terrain envelope around airport runways longer than $3\,500\text{ ft}$, issuing "TOO LOW TERRAIN" alerts if the aircraft descends below the envelope during approach or takeoff.

Runway Field Clearance Floor (RFCF)

A GPWS function that provides a circular protection envelope around airports where the runway elevation is significantly higher than surrounding terrain, triggering alerts if descent below geometric boundary limits occurs.

Runway Overrun Prevention System (ROPS)

An onboard surveillance system composed of Runway Overrun Warning (ROW) during airborne approach and Runway Overrun Protection (ROP) during ground roll to prevent runway overruns.

ROW/ROP Transition Point

The flight condition threshold confirming ground touchdown (e.g., ground spoilers deployed, main gear compressed with autobrake active or speed $< 100\text{ kt}$) that shifts active system logic from airborne ROW to ground-based ROP.

RCDF (Runway Condition Degradation Function)

A ROPS function that automatically downgrades the operational runway condition setting when anti-skid activity reveals worse deceleration than selected, triggering the "RWY COND DEGRADED" FMA message.

Traffic Alert and Collision Avoidance System (TCAS)

An airborne surveillance system that interrogates transponders of surrounding aircraft to calculate collision threat trajectories and generate Traffic Advisories (TA) or vertical Resolution Advisories (RA).

Traffic Advisory (TA)

A TCAS alert triggered when an intruder aircraft poses a potential collision threat with a time to closest point of approach (TAU) of approximately $40\text{ s}$, accompanied by "TRAFFIC TRAFFIC" aural alerts.

Resolution Advisory (RA)

A TCAS alert triggered when an intruder aircraft poses a real collision threat with a time to closest point of approach (TAU) of approximately $25\text{ s}$, commanding vertical flight path avoidance maneuvers via PFD guidance and voice orders.

TA ONLY Mode

A TCAS operational mode where all Resolution Advisories (RAs) are inhibited and converted to Traffic Advisories (TAs), engaged manually for specific operational conditions or automatically below $1\,000\text{ ft}$ AGL.

AP/FD TCAS Mode

An autopilot/flight director vertical guidance mode that automatically engages during a Resolution Advisory (RA) to guide the aircraft along vertical speed targets required to clear traffic conflicts.