Originally Posted by
rickair7777
I wouldn't recommend going green needles 30 miles out with a fed in the JS.
The localizer is only certified out to 18NM...that's why it's so squirrely way out there. Legally you don't have a valid nav signal.
Use the FMS that far out or ask for a vector.
The reception range of the localizer is at least 18 NM within 10 degrees of the on-track signal. There are some places that the signal strength is stronger and can be received further out with better accuracy and includes localizer fixes beyond 18NM, (Rwys in SLC, LAX, SFO, and ATL ) to name a few.
You may hear controllers say "Intercept the Approach Course for 27L" vs. "Intercept 27L Localizer" so be sure what they are saying because this too leaves it up to the discretion of the pilot on how he/she is going to do that. An FMS may work better until the localizer is needed for the published approach segments.
I would agree with rickair777 that 30NM is a tad bit too far.