(h) Deletion of Data. Most data entry
fields may have the associated data deleted by
entering a in the scratchpad and pressing the line
select adjacent to the desired field. In some cases,
the dash entry causes the data to revert to a fixed
default value (e.g., wind to 360º/0).
(3) System Annunciations and Scratchpad
Messages. The CDU will alert the crew of avionics
failures, degraded operations, system modes of
operation or operator entry errors via the CDU
annunciation line and scratchpad. The following three
methods are used:
1. Annunciations on the annunciation
line of the CDU.
2. Scratchpad messages only displayed
locally on the CDU causing the
3. Master CDU alert annunciation is
provided as an external alert in the
pilots primary field of view.
Table 3B -9 provides a list of CDU annunciations
and scratchpad messages.
The scratchpad messages are displayed in
uppercase letters. Some of the messages alternate
with the entered data that caused the message. If a
scratchpad message is simultaneously displayed with
data, the first CLR key activation will clear the
scratchpad message and the next CLR will clear the
Annunciations are displayed in lowercase letters.
annunciation at a time; however, a + marker will
appear to indicate when multiple annunciations are
present. The priority of annunciations is shown in
unacknowledged and lower priority annunciation is
generated. Annunciations are acknowledged by
pressing the CLR key and cycling through the
currently active annunciations.
annunciation is non-clearable and if the CDU master
alert annunciation is also set by the associated
condition. For clearable annunciations, use the CLR
key to clear. If data or scratchpad messages are in
the scratchpad, the CLR key will first clear the
scratchpad before clearing the annunciation line.
Table 3B -10 shows the priority of the CDU
annunciations (highest priority at top of list).
Table 3B-9. CDU Annunciations and Scratchpad Messages
ACTIVE CHANNEL Attempting to perform an
ERF on a hopset that is the
currently tuned preset on
An alternate flight plan has
been selected to be added
to the flight plan.
Clear key or
insertion of the
plan into the flight
ALTN FPLN FULL
Attempt to insert more than
60 legs into the alternate
Attempt to tune to an anti-
jam preset that contains a
Have Quick net when the
V/UHFs preset contains a
SINCGARS net, and vice