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2 Answers

OBS setting ILS Localizer

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Instrument Rating

Im working on an instument rating with one ILS vor I was taught to set obs with the radial of the ILS at the bottom of the dial. Many of the approaches have me intercept 4 or five radials to identify intersections or for a missed approach trails . Ive been setting all radials to bottom making it easier to navigate to the radials. I getting to where i can fly with all the radials I need on the bottom. Making it easy to dial them in. I then go to instrument check ride in FSX and tells me I didnt set obs corectly. Is this a bust on a checkride? 

2 Answers



  1. EAD on Jul 02, 2017

    I think someone may be teaching you backwards or I am misunderstanding what you are saying. My response is based on the former.

    The ILS will indicate properly regardless of what you have the OBS set to, but good practice is to set the inbound course at the TOP of the VOR so that it would match the heading on your DG while you are tracking inbound (I’m ignoring crab angles from wind, of course). I.E. You’re tracking the localizer inbound on the ILS for runway 18, your DG should read 18 (or S) and your VOR should have “18” at the top.

    Tracking VOR radials is a little more complex of an answer since it depends if you are heading inbound or outbound from the VOR along the radial. If you are south of the VOR heading inbound to the VOR along the 180 radial (you are flying a heading of 360) then your VOR should have “0” at the top, “18” on the bottom, and the to/from flag should indicate “TO” until passing the station where it would automatically flip. You still

    If you have “18” at the top but you are flying a 360 heading, you will have reverse sensing so a “fly right” indication would mean the radial is actually to your left (a good way to get lost).

    As for if this would be a fail, I would assume so.
    Task IR.V.A.S3 from the Instrument ACS states “Set and correctly orient to the course to be intercepted.” Improperly setting the course by 180 degrees (and not recognizing or correcting the error) would likely cause a disqualification.

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  2. alaslistas on Jul 04, 2017

    Here is an old post AdamFrisch
    20th Mar 2012, 16:42
    I just recently learned this myself during my instrument training in my aircraft. My old twin only has one VOR/ILS, so I have to switch frequency constantly on the same instrument to catch cross radials. It’s a crazy archaic way to do it, but it will have to do for now until I install more fancy stuff. But on my first ILS approaches I set the track in the OBS, then switched and turned the OBS for my stepdown radials. My instructor just said don’t bother setting the ILS track (but know it), just set the next cross radial, as the ILS will be the same whatever you put in. It was a great revelation and it reduced my workload from insanity, to just crackers..;)

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