Archived files show Soviet Union used civil airliners to conduct secret Cold War spying missions over Britain
Aircraft would veer off their approved flight paths to carry out missionsDefence Secretary said RAF was monitoring monthly flights through UK
09:13 GMT, 28 December 2012
Defence Secretary John Nott in 1982, who informed prime minister Margaret Thatcher in December 1981 that the RAF was monitoring the hundreds of monthly flights through UK airspace by Warsaw Pact airliners
The Soviet Union used civil airliners to conduct secret Cold War spying missions over Britain, according to newly published Government files.
Some aircraft would switch off their transponders, alerting air traffic controllers to their position before veering off their approved flight paths to carry out aerial intelligence-gathering missions over sensitive targets, papers released by the National Archives under the 30-year rule show.
In a memorandum marked Secret for UK US Eyes Only, Defence Secretary John Nott informed prime minister Margaret Thatcher in December 1981 that the RAF was monitoring the hundreds of monthly flights through UK airspace by Warsaw Pact airliners.
'One incident of particular interest
took place on 9th November, when an Aeroflot IL62 made an unauthorized
and unannounced descent from 35,000 ft to 10,000 ft just below cloud
level, to fly over RAF Boulmer, a radar station currently being
'It subsequently climbed back to 37,000 ft,' he wrote.
'During this manoeuvre its Secondary
Surveillance Radar which automatically broadcasts the aircraft's height
was switched off, though it was on before and after the incident.
'It must, therefore, be assumed that it was switched off intentionally to conceal a deliberate and premeditated manoeuvre.'
'Our investigations have now revealed
it was the same aircraft which over flew the USN base at Groton when the
first Trident submarine was being launched. You will recall that as a
result of this incident the President banned Aeroflot flights over the
USA for a short period.'
But that was not the only example of bad behaviour by enemy spies that year.
In August 1981 the Second Secretary at the USSR embassy VN Lazin became the first Soviet diplomat for a decade to be expelled for 'activities incompatible with his status'.
The Foreign Office informed No 10 that Lazin, actually the senior member of the scientific and technical intelligence section of the KGB in London, was arrested during a 'clandestine meeting' with a Portuguese national.
'He developed his relationship with the Portuguese national over several months and sought to obtain technical and scientific information in the UK from him and to use him as an agent with the possibility of eventually placing him in a Nato post,' the Foreign Office noted.
The Soviets responded in traditional fashion with the tit-for-tat expulsion of the British cultural attache in the Moscow embassy.
Margaret Thatcher, pictured, was made aware that the Soviet Union was using civil airliners to conduct secret Cold War spying missions over Britain
More was to follow six months later in February 1982 when MI5 decided to call time on the espionage career of another Soviet, Vadim Fedorovich Zadneprovskiy, a member of the Soviet trade delegation whom for the previous five years operated as a KGB agent-runner.
His recruits included a British businessman who was given the codename court usher.
'Since 1977 he has been observed on many occasions taking prolonged and complicated anti-surveillance precautions during journeys in the London area and he has made frequent journeys lasting some hours to the outer reaches of the free travel area for Soviet officials for no apparent reason, usually indications of agent-running or other intelligence activity,' the Foreign Office reported.
'He has tasked COURT USHER to cultivate contacts in GCHQ and in areas of electronic research and development, to obtain various embargoed items and to provide sensitive information on equipment and procedures used by Special Branch and the Security Service (MI5).
'He has also used COURT USHER on two occasions to deliver equipment in a thoroughly clandestine manner in Vienna to a KGB officer who was expelled from the UK in 1971.'
MI5 allowed Zadneprovskiy to operate from 1980 in an attempt to find out how much the KGB knew about UK surveillance equipment and techniques but after hopes of 'turning' him to work for British intelligence were abandoned, it was decided that he too should be declared 'persona non grata'.