Hijacking is the unlawful seizure of a vehicle, plane, or boat, by force or threat. Recently, hijacking has become synonymous with skyjacking, and especially refers to those who skyjack to make a political point, to seek asylum, to gain revenge or the release of prisoners, or to obtain other concessions. The safety of persons and property is jeopardized, and the operation of air services is seriously affected. Often, under ransom terms, prisoners are released. Increased security measures on the ground and in the air, although apparently successful, may well result in increased cunning, resourcefulness and determination to thwart such measures.
Fantasies of flying, flight, defying the force of gravity, etc, seem to be widespread and to predispose some individuals to carry out dramatic acts such as skyjacking; and certain physical conditions such as vestibular system (inner ear) anomalies may contribute to such predisposition.
The first known skyjacking was in 1930, the next in 1947, but from then on it became far more common. Between 1930 and 1960 (30 years) there were 33 skyjackings; between 1961 and 1965 (5 years) there were 22. In 1971 alone there were 87. It is clear that the two decades from 1960 to 1980 have seen the emergence of a worldwide threat to air travel, with great increases from 1968 onwards. By 1970, the occurrences of violent acts such as unlawful seizure of aircraft and other forms of unlawful interference with civil aviation had reached dangerous proportions, although there has been a downward trend since then: there were 17 "successful" skyjacks in 1984, and 17 failed, compared with 373 failed hijacks in 1973.
The problem could be alleviated in four possible ways: (a) [Prevention], through society's unwillingness to contribute to the crime by paying of ransom, feeding suicidal appetites or pandering to urges for notoriety. (b) [Control], through a collection of airport-related techniques to detect potential offenders or produce fear within them so they do not go through with a planned act (guards, personal searches, magnetometers). (c) [Management] - overt behaviour of crew members to manipulate environmental factors known to them. (d) [Disposition] - the legal and/or psychiatric treatment of the offender, and the discovery of any common factors leading to such aberrant behaviour.