Conroy Virtus

Virtus
Artist's concept of the Virtus
Role	Outsized cargo aircraft
National origin	United States
Designer	John M. Conroy
Built by	Turbo-Three Corporation
Status	Canceled
Primary user	NASA
Unit cost	US$12.5 million (est.)
Developed from	Boeing B-52 Stratofortress

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.

The Space Shuttle was originally designed to utilize on-board turbofan engines for propulsion within the atmosphere, both upon re-entry and for ferry flights between landing sites, such as Edwards Air Force Base, the White Sands Missile Range, or contingency landing sites such as Easter Island, to the launch site at Kennedy Space Center at Cape Canaveral. When the air-breathing engines were deleted from the Shuttle design due to cost and weight concerns, a requirement arose for a transport aircraft capable of carrying the Shuttle from landing sites back to the Kennedy Space Center. 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.