Alerting; Ap Disconnect Alerting; Altitude Alerting; Ri M Runaway Alert I Ng - Honeywell BENDIX/KING KAP 140 Maintenance Manual

2.8 ALERTING

The FCC will provide aural and visual alerting for the conditions described below. The aural alerts
consist of standard--frequency alerting tones, followed, if enabled, by a voice synthesized
message describing the event. The audio alerting circuitry is powered from a separate audio
power bus, to provide independence from autopilot power.

2.8.1 AP DISCONNECT ALERTING

Whenever the autopilot is disengaged, the FCC provides an aural alert. In addition to the audio
alert (unless the disconnect is caused by a loss of autopilot power), the alert tone is then followed
by the voice message: "Autopilot disconnect". With voice messaging disabled, the disconnect
aural alert simply consists of a continuous 2.0 second tone.
In addition to the aural alert, the FCC generates a visual alert by flashing an external disconnect
annunciation for 5.0 seconds following the disconnect. The flashing duty cycle is 66% +/--10%,
with a period of 600--800 ms. The FCC also provides a flashing "AP" display in the roll coupled field
with the same duration and flashing.

2.8.2 ALTITUDE ALERTING

Aural alerting (five "beeps") is provided for altitude alerting. Two alert regions are defined: an outer
band (200 to 1000 feet from the selected altitude) and an inner band (less than 200 feet from the
selected altitude). The altitude aural alert output is active when the aircraft enters into the outer
band from the outside. The alert is followed by the voice message: "Altitude". The FCC also
provides an alert followed by the message "Leaving altitude" when the aircraft is leaving the inner
band. No alert tone or message should be generated when the selected altitude is changed; these
are generated only in response to a pressure altitude change.
An ALERT annunciation is also provided for the Altitude Alerting function. This annunciation is
illuminated continuously anytime the aircraft is in the outer band. It is solid (i.e. not flashing) if the
aircraft was previously outside the outer band; it is flashing if the aircraft was previously in the inner
band. It also flashes for 2.0 seconds the first time the aircraft crosses the Selected Altitude after
being in the outer band.
2.8.3 TRIM RUNAWAY ALERTING
When a trim failure is detected by the trim runaway monitor, the FCC provides a continuous alert
tone (500 ohms and tone alert) until the AP DISC switch is pressed. The tone then ceases. If PFT
detects a failure of the trim runaway monitor, it also produces the same alerting tone and ensures
that the monitor is left in the failed state (to provide a remote TRIM FAIL annunciation).
Revision 2, Dec/2002
CS:15574F02.IDU
BENDIX/KING
KAP 140
Page 2--11