The newspaper said on Monday that the Gulfstream V turbojet has been seen at US military bases around the world, often loading up hooded and shackled suspects and delivering them to countries known to use torture.
The daily investigated the ownership of the jet, tail number N379P, which has been spotted in Afghanistan, Indonesia, Iraq, Jordan, Kuwait, Libya, Morocco, Pakistan, Saudi Arabia and Uzbekistan, according to the newspaper.
The officers of the plane's corporate owner, Premier Executive Transport Services, are all listed with dates of birth in the 1940s, 1950s and 1960s, but with social security numbers issued since 1998.
However, the newspaper was unable to locate any further business or credit information on them or on the company.
The CIA refused to comment, but such "proprietary" or front corporations are standard procedure for the agency, former operatives told The Washington Post.
The "rendering" of suspects to countries that employ interrogation techniques banned in the US is worrying and could violate the UN Convention on Torture, World Organisation for Human Rights USA executive director Morton Sklar said.
The article confirmed much of a 14 November article published in the British weekly newspaper The Sunday Times which obtained flight plans for the plane, which, it said, always departed from Washington and had visited the US navy base at Guantanamo Bay, Cuba, where about 550 suspects are held.
Rights groups say Guantanamo
Bay is a concentration camp
Swedish television programme Cold Facts reported that in December 2001, the jet took hooded prisoners to Egypt, according to The Washington Post, which confirmed the Swedish report independently.
The paper said the plane, with hooded crew members speaking with US accents, loaded two Egyptian nationals and took off at 4.30am for Cairo.
It said airport officials and amateur plane spotters, some using binoculars, had logged multiple sightings of N379P at several US military airports and fuelling stations.