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ADF?? HELP PLEASE!!

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jdog4592:
For those of you who play FSX (Flight Simulator X) The ADF (Automatic,Direction,Finder) is an instrument i havnt quite figured out how to use or more importantly... what it does. If you can help me or show me a site that can that would be wonderful. im 16 and trying to prepare for a carrier of aviation.(probably US ARMY)

KSYR-pjr:
The NDB (non directional beacon) is a ground-based navigational aid akin to a simple radio tower.  In other words, the tower transmits a "non-directional" radio signal, very similar to an AM radio station broadcast.  In fact, the ADF instrument on-board, which is used to point to an NDB, can also be used to tune AM radio stations.

For an excellent explanation of NDBs and ADF instruments, see here:  http://www.navfltsm.addr.com/howitbegan.htm

It is important to note that, at least here in the US, GPS is slowly taking over for all ground-based navigation (with the exception at this time of replacing existing ILS approaches).  The first casualty in this technological paradigm shift is the NDB/ADF, with VORs soon to follow.   The FAA has been decommissioning NDBs across the US at an accelerated pace.   Many aircraft these days are not even equipped with ADF instruments.

Therefore, in my opinion if I were you I would concentrate on understanding GPS rather than ADF, since the ADF will soon be totally extinct.

captray:
I don't play FSX but I am a pilot and instructor. So here goes; The ADF needle points to the station, it can be an AM radio station too. It does not account for wind drift. It will only let you home to the station. Homing is when you keep turning the airplane to keep the needle on the nose. You will eventually arrive at the station but it will be a circuitous route.
There is another instrument that some aircraft have, it's called an RMI (Radio Magnetic Indicator) what it does is that it puts the ADF needle on top of a DG (directional gyro) this was considered way cool when it first came out.
If you don't have a RMI then mentally you must put the ADF needle over the DG to get a picture of what is happening outside.
There are many tricks to keeping on course, but I will try to keep this simple. If you are headed towards the station (needle pointed forward) and you hold a constant heading, in no wind you will be spot on.
If the wind is from the left the needle will point left as you drift off course. To correct you need to turn into the wind (left) how far depends on how strong he wind is.
A good rule is double the degrees off course. So if you are 10 degrees right of course (wind pushing from the left) turn left 20 degrees. When the needle settles at 20 degrees right of course take out 10 degrees of correction and you should stay on course. The 10 left will be your wind correction.

Belive it or not I still have to do NDB approaches in the G4 as there are some that are not in the FMS database. It was and is a cheap reliable navigational aid.

KSYR-pjr:

--- Quote from: captray on March 15, 2009, 11:53:22 AM ---Belive it or not I still have to do NDB approaches in the G4 as there are some that are not in the FMS database.

--- End quote ---

NDB approaches here in the US or in other countries?  It seems from your avatar that you are all over the globe with that G4.

captray:
Mostly Caribean, some in Canada and India. The FMS won't do anything that is a circle to land. Only does DME arcs and straight ins.

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