So come on some one must have a view about how FM interference would manifest itself while tracking a VOR and whether the pilot would spot the problem and what he would do about it.
The aircraft I fly is FM immune, it also mode S all done before any of this became mandatory and all at substantial cost. I sometimes wonder why particularly when I often ask for verification of my mode S and have yet to find anyone able to do so - the usual comment is "we only wish we could".
If I rented an aircraft and found the VORs were placarded not FM immune and I had to fly IFR outside controlled airspace would I - I think I would
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