PRIMUS
r
1000 Integrated Avionics System
A28--1146--112--00
Troubleshooting
9-2
Rule 1
states that system conditions must be considered before the
writeup is made. To aid in determining these conditions, the following
type of questions must be answered.
D
Are any flags in view or fault annunciators lit (obvious problems)?
D
Is the problem in pitch, roll, or yaw axis or a combination thereof?
D
Is the problem present in all modes or only under specific conditions
such as:
-
Flaps or gear up or down, or speed brakes in or out
-
Certain aircraft power configuration
-
Certain speed
-
Certain altitude
-
Two or more modes
-
Certain sequence in mode selection
-
Specific radio frequencies (NAV or COM)
-
When keying a transmitter
-
When weather radar is operating
-
Certain electrical configurations (are all circuit breakers in)?
D
Does the autopilot follow the commands as shown by the flight
director command cue and horizontal situation indicator lateral
deviation bar?
D
Can the pilot fly the flight director commands with the autopilot
disconnected?
D
Does some problem exist with autopilot engaged in a heading hold
and pitch hold mode?
D
In radio modes, are certain conditions, such as another aircraft in
front of LOC or GS transmitter (overflight disturbances), VOR beam
scallops, etc., present?
Rule 2
states that an adequate description must be made when making
a writeup. The description should define the problem and should always
include the specific conditions under which the problem exists, such as:
D
Flags showing (which ones, if any)
D
Mode or modes selected.
D
The IAS present when the problem occurs
D
Period and magnitude of any oscillations
D
Do any inputs fail to work (such as heading bug when in HDG
mode)?
NOTE:
The preceding paragraphs are not intended to cover every
possible system problem. They should be used as guides in
preparing a pilot writeup.