astronautix.com | Lunar Orbit Gemini |
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Gemini/Transtage-LEO Translunar Gemini with Double Transtage - LEO Configuration Credit: © Mark Wade. 4,989 bytes. 635 x 251 pixels. |
On June 24, 1965, McDonnell-Douglas and Martin Marrietta provided a detailed proposal to launch a refurbished, modified Gemini around the moon by April 1967 for $ 350 million. The Gemini would have 521 kg of mass deleted, half of it by removing the solid fuel retrograde rockets used to initiate re-entry (the liquid fuel Orbital Manoeuvring System would be reengineered to increase its reliability). The Titan 2-launched Gemini would rendezvous and dock with a Titan 3C-launched 'Double Transtage'. The Double Transtage consisted of an unmodified first Transtage that would place itself and a second Transtage into low earth orbit. The first Transtage retained the navigation and manoeuvring systems necessary to move the assembly to the rendezvous orbit with Gemini. The second Transtage would be stripped of unnecessary equipment (the orbital manoeuvring system) but was equipped with an Agena-type docking collar.
![]() | Gemini Variants - Modest modifications of Gemini proposed by McDonnell Douglas as a follow-on to the basic program (927 x 723 pixel version). Credit: McDonnell Douglas. 43,356 bytes. 927 x 723 pixels. |
![]() | Lunar Orbit Gemini - Lunar Orbit Gemini. In this version a Gemini docks with a Titan 3C-launched transtage, which maneuvers the Gemini into a lunar orbit and then returns it to earth. Credit: McDonnell Douglas. 11,822 bytes. 469 x 164 pixels. |
![]() | Gemini/Transtage-TLI - Translunar Gemini with Transtage - Translunar Configuration Credit: © Mark Wade. 3,548 bytes. 437 x 223 pixels. |
Craft.Crew Size: 2. Design Life: 14 days. Total Length: 11.7 m. Maximum Diameter: 3.0 m. Total Habitable Volume: 2.55 m3. Total Mass: 15,200 kg. Total Propellants: 10,600 kg. Primary Engine Thrust: 7,257 kgf. Main Engine Propellants: N2O4/UDMH. Main Engine Isp: 311 sec. Total spacecraft delta v: 3,600 m/s. Electric system: 2.20 total average kW. Electric System: 150.00 total kWh. Electrical System: Fuel Cells.
Gemini contractors proposed to launch a refurbished, modified Gemini around the moon by April 1967 for $ 350 million. The Titan 2-launched Gemini would rendezvous and dock with a Titan 3C-launched 'Double Transtage', which would propel the Gemini into a circumlunar trajectory. McDonnell-Douglas and Martin Marrietta's proposal was suppressed by NASA as a threat to the Apollo program.