Big Gemini (or "Big G") was proposed to

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

McDonnell Douglas McDonnell Douglas was a major American aerospace manufacturing corporation and defense contractor, formed by the merger of McDonnell Aircraft and the Douglas Aircraft Company in 1967. Between then and its own merger with Boeing in 1997, it produ ...

in August 1969 as an advanced version of the

Gemini Gemini may refer to: Space * Gemini (constellation), one of the constellations of the zodiac ** Gemini in Chinese astronomy * Project Gemini, the second U.S. crewed spaceflight program * Gemini Observatory, consisting of telescopes in the Northern ...

spacecraft system (albeit actually having little in common). It was intended to provide large-capacity, all-purpose access to

space Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually consider ...

, including missions that ultimately used

Apollo Apollo, grc, Ἀπόλλωνος, Apóllōnos, label=genitive , ; , grc-dor, Ἀπέλλων, Apéllōn, ; grc, Ἀπείλων, Apeílōn, label=Arcadocypriot Greek, ; grc-aeo, Ἄπλουν, Áploun, la, Apollō, la, Apollinis, label= ...

or the

Space Shuttle The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program na ...

Big Gemini

The study was performed to generate a preliminary definition of a logistic

spacecraft A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, p ...

derived from Gemini that would be used to resupply an orbiting

space station A space station is a spacecraft capable of supporting a human crew in orbit for an extended period of time, and is therefore a type of space habitat. It lacks major propulsion or landing systems. An orbital station or an orbital space station i ...

. Land-landing at a preselected site and refurbishment and reuse were design requirements. Two baseline spacecraft were defined: a nine-man minimum modification version of the

Gemini B The Manned Orbiting Laboratory (MOL) was part of the United States Air Force (USAF) human spaceflight program in the 1960s. The project was developed from early USAF concepts of crewed space stations as reconnaissance satellites, and was a s ...

called ''Min-Mod Big G'' and a 12-man advanced concept, having the same exterior

geometry Geometry (; ) is, with arithmetic, one of the oldest branches of mathematics. It is concerned with properties of space such as the distance, shape, size, and relative position of figures. A mathematician who works in the field of geometry is c ...

but with new, state-of-the-art subsystems, called ''Advanced Big G''. Three launch vehicles-

Saturn IB The Saturn IB (also known as the uprated Saturn I) was an American launch vehicle commissioned by the NASA, National Aeronautics and Space Administration (NASA) for the Apollo program. It uprated the Saturn I by replacing the S-IV second stage (, ...

Titan IIIM The Titan IIIM was a planned American expendable launch system, intended to launch the Manned Orbiting Laboratory and other payloads. Development was cancelled in 1969. The stretched core stage was used on some versions of the Titan IIIB and the ...

, and

Saturn INT-20 The Saturn INT-20 was a proposed intermediate-payload follow-on from the Apollo Saturn V launch vehicle. A conical-form interstage would be fitted on top of the S-IC stage to support the S-IVB stage, so it could be considered either a retrofitted ...

(

S-IC The S-IC (pronounced S-one-C) was the first stage of the American Saturn V rocket. The S-IC stage was manufactured by the Boeing Company. Like the first stages of most rockets, most of its mass of more than at launch was propellant, in this case ...

/ S-IVB) were investigated for use with the spacecraft. The Saturn IB was discarded late in the study. The spacecraft consisted of a crew module designed by extending the Gemini B exterior cone to a 419-cm-diameter

heat shield In thermodynamics, heat is defined as the form of energy crossing the boundary of a thermodynamic system by virtue of a temperature difference across the boundary. A thermodynamic system does not ''contain'' heat. Nevertheless, the term is al ...

and a cargo

propulsion Propulsion is the generation of force by any combination of pushing or pulling to modify the translational motion of an object, which is typically a rigid body (or an articulated rigid body) but may also concern a fluid. The term is derived from ...

module. Recovery of the crew module would be effected by means of a gliding parachute ( parawing). The parametric analysis and point design of the parawing were accomplished by Northrop-Ventura Company under a subcontract, and the contents of their final report were incorporated into the document. The landing attenuation of the spacecraft would be accomplished by a skid landing gear extended from the bottom of the crew module, allowing the crew to land in an upright position. The propulsion functions of transfer, rendezvous, attitude control, and retrograde would be performed by a single liquid propellant system, and launch escape would be provided by a large Apollo-type

launch escape system A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, suc ...

. In addition to the design analysis, operational support analysis and a program development plan were prepared. The concept was given serious consideration. In 1971, faced with budget cuts which rendered the development of a fully-reusable space shuttle infeasible, NASA administrator George Low lamented that shuttle development might have to be delayed until the 1980s, with "something like a "big G" approach and a cheap space station" filling in as an interim. The

Office of Management and Budget The Office of Management and Budget (OMB) is the largest office within the Executive Office of the President of the United States (EOP). OMB's most prominent function is to produce the president's budget, but it also examines agency programs, pol ...

was much more favorable to the idea than NASA, concluding in a staff paper that Big Gemini launched aboard an uprated Titan III would be a more cost-effective option than any shuttle design. Ultimately OMB Deputy Director Caspar Weinberger helped to broker a compromise where Big G was taken off the table and NASA was given the greenlight for immediate development of a partially-reusable thrust-assisted orbiter shuttle.

Specifications

* Crew size: 9 to 12 * Length: * Maximum diameter: * Habitable volume: * Mass: * Payload: * Launch vehicles: Titan 3M, Saturn IB, Saturn S-IC/S-IVB.

References

External links

Big Gemini – Encyclopedia Astronautica

{{Gemini program Crewed spacecraft Cancelled space missions Project Gemini

Big Gemini

Specifications

See also

References

External links