Violations of Controlled Airspace - Special Study 1997

A VCA occurs when a pilot enters controlled airspace without a
clearance. Controlled airspace is a section of airspace surrounding
an airport with a tower, and/or airspace up to a certain altitude
overlying Australia. This airspace may or may not be radar
monitored. The controller needs to be aware of all aircraft within
hisher section of controlled airspace so as to provide a complete
traffic service. Pilots are required to request a clearance before
entering the airspace.