Becker BD406 - Course Deviation Indicator (CDI) - Beacon;Navpoint Detailed Menu; Figure 42: Mission Mode - CDI, Angular Definition for Fixed Position in Beacon;Navpoint Detailed Menu; Figure 43: Mission Mode - CDI, Distance Definition for Fixed Position in Beacon;Navpoint Detailed Menu

Operation
Becker Avionics
94 BD406/PBD406 DV16401.03 Issue 04 May 2021
Course Deviation Indicator (CDI) – Beacon/NavPoint detailed Menu
-60 FROM
0 FROM
60 FROM
30 FROM
45 FROM
O
O
O
O
O
Indicator TO
is active
Indicator FROM
is active
-30
TO
O
-90
TO
O
90
TO
O
0
TO
O
45
TO
O
Current BD406 Position (updated
continuously from GPS)
Fixed Position
(previously
stored BD406 position)
CDI value
Target (Beacon or NavPoint)
Figure 42: Mission Mode - CDI, Angular Definition for Fixed Position in Beacon/NavPoint detailed Menu
Target (Beacon or NavPoint)
CDI = 0 km FROM
Current BD406 Position (updated continuously from GPS)
Fixed Position (previously stored BD406 position)
CDI = 17 km FROM
CDI = 20 km TO
CDI = 0 km TO
CDI = 14 km TO
CDI = -17 km
FROM
CDI = -20 km TO
CDI = -10 km TO
CDI distance
Figure 43: Mission Mode - CDI, Distance Definition for Fixed Position in Beacon/NavPoint detailed Menu
Course Deviation Indicator (CDI) in Beacon/NavPoint detailed menu shows angular difference
between two courses:
• Defined between coordinates of fixed position and coordinates of the target (beacon or
NavPoint).
• Current coordinates of the device and coordinates of the target.
CDI belongs to range [-90, 90] deg. details see "Figure 42: Mission Mode - CDI, Angular Definition for
Fixed Position in Beacon/NavPoint detailed Menu" page 94.
Indications are not related to the device velocity – only position is in the account.
CDI shows valid values only if target and GPS source supply valid data. If CDI value is valid – a value
of deviation can be calculated in kilometer or nautical miles, details see "Figure 43: Mission Mode -
CDI, Distance Definition for Fixed Position in Beacon/NavPoint detailed Menu" page 94.