Garmin GDL 88 User Manual download pdf (Page 18)

3-2

GDL 88 ADS-B Transceiver Pilot’s Guide

190-01122-03 Rev. A

The following table describes the aircraft that will be observed by a GDL 88

equippedaircraftaccordingtothelevelofequipmentinstalledintheotheraircraft.

Other Aircraft Equipage Viewable by GDL 88

Equipped Aircraft

1090ES Out Equipped Yes

UAT Receive Only Capable No

UAT Transmit Equipped Yes

No Transponder, No ADS-B No

Non ADS-B Equipped, but with Mode C or S Transponder Yes (see Note)

Table 3-1 Aircraft Available for Viewing by an ADS-B Equipped Ownship

NOTE: Only when in ADS-B ground station coverage and when the other

aircraft is in ATC radar coverage.

3.2 Self-Interrogation

ForinstallationswithadigitalinterfacebetweentheGDL88andtheinstalled

transponder, the transponder acts as a single control to enter the transponder

squawkcode,IDENT,andemergencystatus.

Whenadigitalinterfaceisnotavailable,theGDL88isconguredtoutilize

self-interrogation.TheGDL88hasasmall,ultralowpower1030MHztransmitter

integrated into the unit that interrogates the transponder installed in the aircraft.

This interrogation looks exactly like the interrogations received from ground

based surface search radars and the transponder replies like it is designed to do,

toincludethesquawkcode,IDENTstatus,andemergencystatus.TheGDL88

receives this reply and sets the corresponding ADS-B Out message values to match

the received data.

3.3 Pressure Altitude Broadcast Inhibit (PABI)

MuchlikewithModeCtransponders,amethodisrequiredtobeavailableto

the ﬂight crew to inhibit the transmission of pressure altitude in the ADS-B Out

message. This could be used for certain surface operations, in the event of a failure

of an altitude source in the ownship, etc. This control may either be integrated

into the controlling display or as a stand-alone switch installed in the cockpit.

WhileconductingoperationswithinairspacerequiringADS-BOutcompliant

Out transmissions, per 14 CFR 91225, PABI should not be activated unless

directed by ATC.

1 2 ... 13 14 15 16 17 18 19 20 21 22 23 ... 47 48

No comments

Garmin GDL 88 User Manual Page 18