"* Boeing B-52 Stratofortress"@en . "Canceled"@en . "3000"^^ . . . . "Conroy Virtus"@en . . "* Antonov An-225 Mriya\n* Scaled Composites Stratolaunch\n* C-5 Shuttle Carrier"@en . "1.25E7"^^ . . . "300"^^ . "* Myasishchev VM-T\n* Shuttle Carrier Aircraft"@en . "22166"^^ . . "45800"^^ . . "Lowther 2012"@en . "The Conroy Virtus was a proposed American large transport aircraft intended to transport the Space Shuttle. Designed beginning in 1974 by John M. Conroy of the Turbo-Three Corporation, it was to incorporate a pair of Boeing B-52 Stratofortress fuselages to form a new craft utilizing existing parts for cost-savings. While the project was seriously considered, it proved impractically large, and NASA chose to develop the Boeing 747-based Shuttle Carrier from surplus commercial aircraft instead."@en . "35000"^^ . . "United States"@en . "Pratt & Whitney JT9D-3A"@en . . . "4"^^ . "850000"^^ . "high-bypass turbofans"@en . . . . . "450"^^ . . . "Outsized cargo aircraft"@en . . "The Conroy Virtus was a proposed American large transport aircraft intended to transport the Space Shuttle. Designed beginning in 1974 by John M. Conroy of the Turbo-Three Corporation, it was to incorporate a pair of Boeing B-52 Stratofortress fuselages to form a new craft utilizing existing parts for cost-savings. While the project was seriously considered, it proved impractically large, and NASA chose to develop the Boeing 747-based Shuttle Carrier from surplus commercial aircraft instead."@en . . . "9"^^ . "imp"@en . . . .