A terrain awareness warning system (TAWS) is a standard fit in all newly delivered aircraft from Airbus and Boeing. The manufacturers decided to do this well before the US Federal Aviation Administration and the UK Civil Aviation Authority made it compulsory to install the equipment, which they have done during the past nine months

Aircraft collision avoidance systems (ACAS) became compulsory for all users of Europe's controlled airspace this year, and the traffic alert and collision avoidance system (TCAS) has been compulsory in US skies since the early 1990s.

The global positioning system (GPS) has become more or less standard in all airliners. In general aviation aircraft, where it is not normally standard except in the corporate sector, the pilots usually carry their own receiver.

Source: Flight International