This just in:
To: All airlines operating into the United Kingdom
Dear Colleagues,
This message is being circulated to highlight an amendment to the UK AIP with regard to the requirement for use of Squawk A2000 on ground with effect from 12 February 2009. In essence the change seeks to harmonise the use of Squawk A2000 on ground as follows:
"Unless otherwise instructed by ATC, Mode S transponder equipped aircraft on the aerodrome surface should select Mode A code 2000 when under tow; or parked and prior to selecting OFF or STDBY."