Precise satellite navigation could remove the need for aircraft to fly longer routes that were partly designed around the old system of ground-radio beacons.

ECONOMIST: A jam at 32,000 feet

Each probe can pick up GPS signals and signals from eLoran, an enhanced version of Loran, the ground-based terrestrial radio-navigation system first used by the American and British navies during the second world war.

ECONOMIST: GPS jamming

It has been discovered that the Airwave radio system's signal is variable on the ground floor.

BBC: Suffolk Police radio fault at Landmark House in Ipswich