A Russian surveillance plan recently flew over several US military bases, including area 51, perhaps America's most secretive military site.
The aircraft, a Tupolev 154, was first seen in Northern California last week, according to CBS Sacramento. The news in the flight mission, which took place under the Open Cloud Treaty and took place on March 28, was first reported by The Drive.
Under the agreement, which was first proposed by President Dwight Eisenhower in July 1955 and finally signed in 1992, the treaty "allows each state party to carry out short-term, unarmed, reconnaissance flights across the other territories to collect data on military forces and activities. "
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"The Treaty is also aimed at creating trust and confidentiality among state parties through their participation in the transfers", according to a description of the agreement. There are 34 members of the Treaty, including the United States, Russia and Germany. In particular, China is not a member.
Every observer must give "the host country's minimum 72 hours notice" before departure. The host country has 24 hours to acknowledge the request and must ask the observer whether it can use its own aircraft or to deliver.
In addition, the flight plan must be delivered to the host country (which has 4 hours of notification) and the only changes that can be requested are for security or logistical reasons.
Both the Air Force and the Defense Ministry have not yet responded to a request for comment on this story from Fox News, but an air force spokesman told the CBS News the aircraft was in line with the treaty before it departed on its journey. There were also US observers on board the aircraft to monitor the flight.
The aircraft's transponder shows that it flew over Sacramento, as well as other military sites on the west coast, including Edwards Air Force Base, Coronado Island, Camp Pendleton and Nevada test site now known as Area 51
Final years of speculation, in 2013, the US government finally recognized the existence of the secret area 51, after a number of declassified documents were released.
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