Some interesting background reading on a selective spoofing of GPS from 1996

http://www.iflyamerica.org/gps-were-hooked.asp

Note that the pilot who couldn't find the runway received a false GPS signal, not a blocked GPS signal. It's odd that only now MOD is testing spoofing when USA has been known to have that capability for donkeys years.

"Day VFR flight from Wilmington to Avery County Airport Spruce Pine, NC. Filed VFR flight plan and closed in Hickory, NC. We landed Hickory, NC, and called Avery County Airport for wx into Avery County. Report was minimum haze, good visibility. We departed Hickory with about one hour 45 minutes fuel. We were unable to find the Avery County Airport because of poor visibility. Our GPS told us we were over Avery Airport, but could not see it. New Bern flight watch did not tell us about a NOTAM that all gps systems were inaccurate due to the missile attack on Iraq."

"Here’s a GPS NOTAM issued recently. Note the very large area that could be affected.

GPS 04/009 ZDC GPS IS UNRELIABLE AND MAY BE UNAVAILABLE WITHIN A 275 NM RADIUS OF 2958N/0791500W AT FL400. DECREASING IN AREA WITH A DECREASE IN ALTITUDE TO 229 NM RADIUS AT FL250, 163 NMR RADIUS AT FL100, AND 120 NM RADIUS AT 4000 FT AGL. THE TEST AREA IMPACTS THE WASHINGTON, JACKSONVILLE AND MIAMI ARTCC AIRSPACE. WEF 0604201800-0604202100"

Jammin' GPS - I knew it was a 'cool' invention, but didn't realise just quite how cool!

I'll turn right to get my coat.

With my work address. It's fairly relevant to what I do.