The nail in the coffin: TIS and Mode-S

Paul Tomblin wrote:
If you were using WAAS, you should get to know the WAAS satellite coverage
areas. I think they fixed the problem, but for a while there the coverage
was **** poor is in New Hampshire and Maine.

I don't know if I'd call it "**** poor", but much of Maine and
ocasionally the rest of New England lose LPV coverage often.
Southern California often loses out, too. Here's a real-time
coverage map:

http://www.nstb.tc.faa.gov/vpl.html