The Conroy Virtus was a proposed American large transport aircraft intended to carry 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 using existing parts for cost-savings.
[1][2] 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.
[4] One early design for a shuttle carrier aircraft was proposed by John M. Conroy, developer of the Pregnant Guppy and Super Guppy oversized cargo aircraft, in cooperation with the NASA Langley Research Center; named Virtus, a contract was issued for design and development work in 1974.
[6][7] Data from Lowther 2012[5]General characteristics Performance Related development Aircraft of comparable role, configuration, and era