The MoD has informed Ofcom of the following GPS jamming exercise:

Dates: Jamming will be conducted on a maximum of 3 week-days in the period 10-21 July 2011.Times: 0900 -1730 BST.

Location: Jamming aircraft will orbit at 10,000ft above mean sea-level (AMSL) along a 50nm flightpath on a heading of 270°T from Kirkwall, starting 10nm to the west of Kirkwall and ending 60nm to the west of Kirkwall

Possible areas affected: The GPS jamming is likely to affect civilian Standard Positioning Service (SPS) receivers over a large area. A minimum jammer to signal vulnerability of 30dB has been assumed for a civilian receiver. Signal theory suggests that a SPS civilian receiver should have approximately 32dB of jamming resistance.

Safety of Life Operations: Safety of life operations will take precedence over exercise activities at all times. To this end, the AWC is open to further discussion with any official recipient on the potential implications of this jamming exercise.