SANDEL SN3308 WHEN COUPLED WITH A GARMIN 400W/500W NAVIGATION SYSTEM
Service Alert: 071016-00
AFFECTED PRODUCTS:
All GNS 400W/500W products installed with a Sandel SN3308 EHSI
ISSUE
The Sandel model SN3308 EHSI has a feature called AUTO SLEW. When this feature
is enabled and GPS is the selected navigation source, the SN3308 will automatically
rotate the course pointer to the desired course sent by the 400W/500W Series unit.
When the SN3308 is given a new course from the GPS, it slews to the new commanded
course.
When NAV (VLOC) is the selected navigation source for the SN3308, course selection
is always manual. If the navigation source is switched from GPS to NAV (VLOC) before
the SN3308 has completed slewing to the new course, the course pointer will stop and
may indicate a heading that will not intercept the desired course. Setting the ILS CDI
CAPTURE to ‘Auto’ on the CDI/ALARMS AUX page causes the Garmin 400W/500W
navigation system to automatically change to VLOC as the navigation source when
using GPS navigation to intercept an ILS or localizer approach.
RESOLUTION
The Pilot should always verify the selected course on the SN3308 after any
change to the navigation source (GPS-VLOC/NAV).
Setting the ILS CDI CAPTURE to ‘Manual’ on the CDI/ALARMS AUX page of the
Garmin 400W/500W unit is recommended to disable the automatic switching of the
navigation source (as when the ILS CDI CAPTURE setting is ‘Auto’).
Garmin Service Alert!
