THE Ministry of Defence ordered an investigation of thousands of UFO sightings in the 1990s to examine whether alien spaceship technology could be exploited to build advanced engines for the RAF, according to a new official history.

The book, based on the ministry’s “X-files” of thousands of sightings, shows that an unnamed wing commander initiated the project in 1993 because he believed it was wrong to assume extra-terrestrial craft did not exist.

Nick Pope, who has written on UFOs and was a colleague of the officer at the MoD, confirmed the book’s account: “I remember him saying he believed there was evidence of an exotic propulsion system and the bottom line was that if they had it, we sure as hell wanted it.” Pope would not disclose the man’s name.

Official documents from the wing commander are quoted in the book, written by David Clarke, senior journalism lecturer at Sheffield Hallam University.

The officer wrote that while most of the phenomena would have rational explanations, “if the sightings are of devices not of this earth then their purpose needs to be established as a matter of priority”.

He added: “There has been no apparently hostile intent and other possibilities are 1) military reconnaissance; 2) scientific; and 3) tourism.”

Alien engines, if they existed, were apparently “stealthy” and “do not use conventional reaction propulsion systems”. The wing commander wanted to explore possibilities for “technology transfer”.

The new book, The UFO Files: The Inside Story of Real-Life Sightings, is published by the National Archives in Kew, west London, and is based largely on MoD files released there. It traces the story of UFO sightings in Britain from the first decade of the 20th century.

Through much of the past 100 years, thousands of sightings by people ranging from RAF pilots to police officers and children have been collated by the MoD who believed they could yield evidence of advanced foreign aircraft of which Britain had no knowledge.

Some remain hard to explain, such as foo fighters, the name given to balls of fire that seemed to pursue RAF bombers in the second world war.

It was only in the 1990s, partly at the wing commander’s prompting, that the MoD finally did a systematic analysis of UFO sightings, called Project Condign.

Most were explained by everyday objects, such as airships, clouds or even chinese lanterns, being mistakenly identified as alien craft, or by unusual atmospheric phenomena. No evidence of aliens was found.

A retired senior official at the defence intelligence staff, where the wing commander was employed, said: “Some people had bees under their bonnet ... whenever UFOs were raised at the weekly directorate meetings it was in a fairly light-hearted and dismissive way.”

Clarke’s book shows sightings are still frequent. In 2007 the MoD opened a file on an incident over the sea near Guernsey in which pilots of two planes saw a “sparkling yellow object shaped like a long, thin cigar”.

Last year the MoD’s directorate of air staff logged 285 UFO sightings. The ministry runs a UFO hotline at RAF High Wycombe in Buckinghamshire which the public can telephone with details of sightings. The number is 01494 496 254.

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