14
3700 Osuna Road NE
Suite 711
Albuquerque, NM 87109
www.sandia.aero
Memory Error
On power-on, the unit performs a self-test of the calibration and setup parameters stored in non-
volatile memory. If this test fails, a red MEMORY ERROR message is displayed and the
instrument becomes inoperable. If this occurs, the unit must be returned to the factory for
service.
Figure 16 - Memory Error Message
3.3
Degraded Attitude
During degraded mode, errors in pitch or roll may be observed during long accelerations or
decelerations, however attitude information is always available - it is never removed or made un-
available.
Errors will not exceed TSO limit specifications. When a cross check message is present the SAI-
340A is considered to be in degraded mode. The TSO tested maneuvers represent typical flight.
Degraded mode may occur if a pilot maintains an accelerated frame of reference (i.e. turns) for
greater than 3 minutes.
Degraded Mode maintains basic attitude performance and is sufficient to maintain positive
aircraft control for VFR and IFR operations.
When operating in the Degraded Mode, a yellow CROSS CHECK message may be displayed on
the screen.
Figure 17- Cross Check Message
Cross Check may occur during extended periods of maneuvering. Reestablishing straight and
level flight allows the unit to reacquire TSO criteria performance. The Cross Check message
will automatically clear once normal operations are resumed.
3.4
Transition To and From Battery
The unit will automatically transition to internal battery if the aircraft power drops below
approximately 7 VDC. At this point, one of two operational sequences will occur, depending on
if the aircraft is on the ground or in the air. This logic is tied to the current indicated airspeed as
follows:
•
In Flight: If airspeed is above 40 knots, transition will occur to battery with no pilot
action required. Only the yellow ON BATTERY indication will be shown – no other
popup menus or messages will be presented.
•
On Ground: If airspeed is below 30 knots, a shutdown timer will be displayed. If the
pilot takes no action, the unit will automatically shut-down in approximately 45 seconds.
This is the normal on-ground shutdown sequence.
