• Heading (HDG) Fail Flag: INFO:

  On the Horizontal Situation display the amber HDG flag is displayed. The compass rose, drift angle, and course bug are removed.

  
  

  On the Nav Data Display (ND) the amber HDG flag is displayed. The compass rose, heading, and track line are removed.

  
  
  Note:

  If the Nav Data Display is in the MAP mode a TRK fail flag is shown in place of a HDG Flag.

  
  
  Heading (HDG) Fail Flag Possible Causes:

  Before replacing any component perform BITE if available. (ADIRU-Current Status or Inflight Faults)

  
  

  1.ADIRU

  
  

  2.DEU

  
  

  3.Wiring from the ADIRU to the DEUs

  
  
  Heading (HDG) Fail Flag:

  

  
  

  

  
  Circuit Breakers:

  ADIRU Left (AC): P18-1 = E7.

  ADIRU Left (DC): P18-1 = E5.

  ADIRU Left EXC: P18-2 = E8.

  ADIRU Right (AC): P6-1 = C14.

  ADIRU Right (DC): P6-1 = C17.

  ADIRU Right EXC: P6-1 = C15.

  DEU#1 HOLD UP: P6-1 = D10.

  DEU#1 PRIMARY: P18-2 = D5.

  DEU#2 HOLD UP: P6-1 = D9.

  DEU#2 PRIMARY: P6-1 = D11.

  
  
  Applicable deferrals MEL 34-35 = Inertial Reference System (IRS) and IRS Features
  

Training Only