190-01004-02 GTN 625/635/650 TSO Installation ManualRev. F Page 6-716.13.4 ILS Flight Check (GTN 650)1. Tune an ILS at the local airport.2. Verify the AUDIO IDENT and AUDIO QUALITY have no objectionable electrical interferencesuch as magneto noise.3. Verify the Morse code decoder IDs the station (95% probability).4. Fly the approach.5. Verify NAV flag, GS flag, and CDI and VDI are operational.6.13.5 Autopilot Flight Check1. Enter and activate a flight plan on the GTN. For the GTN 650, ensure that GPS is selected on theCDI. Engage the autopilot in the GPSS mode, if available. Verify that the autopilot flies the course.2. Disengage the autopilot and fly off course. Re-engage the autopilot (in GPSS mode) and verifythat it correctly intercepts the course and continues to fly it.3. Turn off the autopilot GPSS but leave the autopilot engaged in NAV mode. Verify that it maintainsthe current course.4. (GTN 650 Only): Reselect the GPSS mode on the autopilot. Press the CDI key on the display toselect VLOC on the GTN 650. Verify that the GPSS mode disengages.5. For autopilots that provide vertical guidance, fly a vertically coupled LPV approach. Ensure theautopilot correctly flies the approach.6. Deviate from the glideslope by using control wheel steering, or by disengaging the autopilot.Ensure the autopilot correctly follows the approach guidance once re-engaged.6.13.6 TAWS/HTAWS Audio Flight Check (TAWS/HTAWS-equipped units only)The TAWS/HTAWS volume needs to be loud enough to ensure that aural alerts are audible under allanticipated noise environmental conditions. This check verifies that TAWS/HTAWS aurals can be heardduring flight, but the ambient noise conditions under which it is verified are not worst-case. Consequently,the “Five Hundred” callout should be louder than is required for the conditions under which it is verified.1. Set up for an approach to the airport.2. During the approach, at approximately 500 ft AGL, the “Five Hundred” callout will occur. Verifythat “Five Hundred” can be easily heard and understood.6.14 Database CheckCheck the navigation database to ensure it is current. The database information is displayed during the unitdisplay start-up sequence. To check the database:1. Turn off the GTN and then turn it on. The GTN will go through its normal start-up sequence.2. Wait for the Navigation Database page to be displayed.3. Verify that the expiration date displayed has not passed.If the database has expired, then remove the SD card and update the navigation database as described inSection 6.15. Also see Section 1.6.
