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sky marshal also air marshal or flight marshal

noun [countable]

a police officer who is responsible for the safety of passengers flying on a commercial passenger aircraft

'But just as the Government's willingness to put sky marshals on flights to America in defiance of British pilots' wishes before Christmas sent soothing signals, it will be seen in Washington as a symbol that Britain remains serious about dealing with global terrorism.'

The Observer 22nd February 2004

'The life of an air marshal is a lonely one, says David Adams, who has worked undercover on American flights for two years. "The typical day is spent 30,000 feet in the air protecting 200 passengers with no back-up" …'

The Observer 4th January 2004

You're on a flight from London to New York, and as you take a quick trip to use the bathroom, you notice a smartly-dressed man sitting on one of the rear seats. Well, you wouldn't have noticed him, were it not for the fact that you suddenly caught sight of him attending to what looks like a … pistol? Before you start to panic, an explanation suddenly dawns on you – of course, he's there to protect you, not threaten you, he's a sky marshal.

a sky marshal is an 'undercover' police officer, not usually assigned to react to a specific threat, but randomly placed as a deterrent

Not even a full year into the 21st century, and the terrorist attacks in New York on September 11th 2001 heralded a major preoccupation for the new millennium – the war on terrorism. It is in this climate that the term sky marshal has gained considerable ground over the last few years. It refers to an armed guard placed on an international flight for security purposes, and equivalent terms are air marshal and flight marshal. At the time of the 2001 terror attacks, there were only 33 federal sky marshals in the United States. By 2006, this figure had risen to over 1,000. The expression entered more global awareness in December 2003, when a US directive stated that planes using American airspace would be required, when considered necessary, to place sky marshals on designated flights. The move met with considerable opposition in the United Kingdom, notably from the British Airline Pilots' Association. However, though sky marshals are still unusual on British-operated flights, they are used in many other countries, including Germany, Switzerland, India, China, Canada and Australia.

A sky marshal is an 'undercover' police officer, not usually assigned to react to a specific threat, but randomly placed as a deterrent. In theory, passengers should not know whether a sky marshal has been put on a flight or not.

Background – sky marshal

Sky marshals are not a completely new phenomenon and have been used in the United States for over 40 years. Concerned about the growing threat of aircraft hijacking (or skyjacking, a blend of sky and hijacking coined in the early sixties), President John F. Kennedy set up the Sky Marshal Program in 1961. Subsequent presidents boosted the number of sky marshals, including Richard Nixon during the seventies and Ronald Reagan in the eighties, in the aftermath of a serious hijacking (TWA flight 847) in June 1985. But when terrorists started bombing aircraft rather than hijacking them, attention turned to security on the ground, and the number of sky marshals steadily declined – until the terrorist attacks of September 2001.

The term sea marshal is used for similar officers placed on ocean-going cruise ships.

by Kerry Maxwell, author of Brave New Words

This article was first published on 25th June 2007.

Open Dictionary


a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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