The history of in-flight security began in March 1971 when the US Federal Aviation Administration (FAA) directed a program to combat airplane hijackings.
In response to the September 11 attacks, the commonwealth instituted an air security officer (ASO) program under the Australian Federal Police in December 2001.
[5] The ASO Program provides a discreet anti-hijacking capability for Australian civil aviation by putting armed security personnel on board aircraft.
Pilots and flight attendants are advised of their presence and the officer is authorized to physically intervene should an unauthorized person attempt to gain control of an aircraft.
[13] Following the September 11 attacks, private operators like Air Sahara also introduced sky marshals on some flights and stated plans to increase these.
The ASF was established in 1976 under the Airports Security Force Act LXXVII of 1975, initially as the directorate within the Department of Civil Aviation.
After the hijacking of a Pakistan International Airlines aircraft in March 1981, sensing the contradictory requirements of security and facilitation, the ASF was separated, and, in December 1983, was placed under the folds of the Ministry of Defence.
Members are usually from either the air marshal unit, the security command or the special tactics and rescue (STAR) of the Singapore Police Force.
An armed Air Marshal program began operating in the United Kingdom in 2002, it was in response to growing threats to civilian passenger aircraft.
Under the Visible Intermodal Prevention Response (VIPR) system, started around 2005, federal air marshals began to patrol non-aviation sites like bus terminals and train stations.