• Vertical Flag (VERT): Notes:

  On those aircraft that have only 2 VHF Nav receivers, the VHF Nav XFR switch is labeled "Both On 1" or "Both On 2." The results previously described using the XFr switch should be the same.

  
  VERT Flag In-view (HSI SW in VOR/ILS, ILS Freq tuned):

  1.With the HSI selector switch on the glareshield in the VOR/ILS position, observe the G/S flag on the ADI directly above the HSI with the VERT flag inview:
  
  2.If the G/S flag is not in-view on the ADI, then the problem is with the HSI. To further verify move the VHF Nav XFR switch on the P5 overhead panel to "Capt On Aux" or "F/O On Aux" and observe the VERT flag:
  
  2a.If it stays in-view with a different nav source then its the HSI is at fault.
  
  2b.Run the ILS self-test on the VHF Nav control panel and observe the indications on both the ADI and HSI. If the HSI VERT flag is in-view throughout the test but the ADI G/S flag is not then the HSI is bad.
  
  3.If the VERT flag on the HSI and the G/S flag on the ADI above it are both in-view, then you have a source problem. Do the following to verify:
  
  3a.Run the ILS self-test on the VHF Nav control panel and observe the indications on both the ADI and HSI. If both the ADI and HSI do not indicate a proper glide slope test results then the nav source is the problem. Proceed to trouble shoot the VHF nav receiver.
  
  3b.You can move the VHF Nav XFR switch on the P5 overhead panel to "Capt On Aux" or F/O On Aux" and run the self-test again using a different nav receiver in place of the normal source.

  
  ADI INFORMATION:

  

  
  Circuit Breakers:

  VOR/LOC #1: P18-1 = A1.

  VOR/LOC #2: P6-1 = A15.

  Glide slope 2: P6-1 = A16.

  Glide slope 1: P18-1 = A2.

  F/O XFMR (ALT): P18-2 = B4.

  Capt cmps xfmr (ALT): P6-1 = B12.

  Instrument Transformer 2: P6-1 = A12.

  Instrument Transformer 1: P18-2 = A1.

  
  
  Notes:

  With HSI switch in VOR/ILS position and a VOR frequency set (108.00) the vert flag should be biased out of view. With a ILS frequency set (108.10) the vert flag will be in view without a valid glide slope signal being received. Must perform a ILS nav head test or grab a tic30 box while on ground.

  
  Applicable deferrals 34-17=VHF ILS System.

Training Only