14.30 When both NDB's and VOR's are available, is one preferable over the other?
From FlightSim
NDB's in the US are only used mainly as approach aids. They are commonly colocated with the outer marker of an ILS or LOC approach. This is called a Locater Outer Marker. In this case the NDB will have the first two letters of the associate localaizer as it's id. For example, the localizer to runway 35R at OKC is I-RGR, so the GALLY LOM ID is RG. An LOM is used as the initial approach fix in a non-radar environment. Many NDB's are also located on an airport, allowing an NDB approach to that airport.
A clearance to an LOM is usually accompanied by your approach clearance. As an example, a sample clearance might be, "Arrow 43F is cleared direct GALLY, cleared for ILS 35R approach." There's an adventure in FS where you fly an ILS into an island on Long Island (ISP?) In this case you are cleared to the LOM for the ILS. When you reach the LOM you are expected to establish yourself inbound on the localizer. This requires a procedure turn (that's another can of worms).
Also, there might just not be a VOR placed where you need to go!
MDK
Or it might be out of range. There are also still a FEW locations in the US
that have ONLY an NDB approach, but they're getting scarce since the advent of
GPS approaches.
Larry N.
