SPACE IN MINIATURE

In 1962 and 1963, Lockheed Missiles and Space Company (LMSC) examined the man-to-the-planets problem under NASA's EMPIRE (Early Manned Planetary-Interplanetary Round-trip Expeditions) study. A baseline requirement was that the missions would be launched on Saturn V, or upgraded Saturns, with or without nuclear upper stages. Use of Apollo equipment was also emphasized to reduce cost and development time.

LMSC proposed a manned artificial-gravity flyby ship, suitable for manned missions to Venus or Mars. Missions past Venus in 1974 would take 370 to 450 days, and past Mars 670 to 750 days, depending on upper stages and launch time. The flyby trajectory would propel the spacecraft into a near grazing encounter of the target planet, returning to Earth with no major propulsive changes.

The flyby missions would provide "a total integrated system of data sensing, processing, correlation, and evaluation geared to supply planetary data for future designs related to manned landings and exploration of Mars." Also "The planetary flyby best-use might be for operational testing of future-mission equipment and possibly accurate insertion of a reliable unmanned reconnaissance orbiter or lander." * Possible sample return was also studied in 1965.

The LMSC proposal was based on a three-man crew using a modified Apollo Command Module as a launch carrier and Earth entry vehicle. A new Retro Module would be used for crew transfer, capture of surface material from a sampling probe, and delta V at mission end to reduce Earth entry speed to manageable G-loads on the crew and thermal loads on the CM. This combination is known as the CRM.

The three spoke rotating craft would provide 3/8 G using a 25-meter long radius and rotation of 3.8 rpm. This was selected to keep spoke lengths short, but place the crew out of the danger of disturbing Coriolis forces and dizziness. **

Due to the rudimentary nature of solar cells in 1963 and the great distance from the Sun as the craft flew past Mars, a nuclear power source was proposed. The craft would use the 8-kilowatt SNAP 8 system, with an active thermal cooling loop using liquid sodium. Located far from the hub on it's own spoke, and behind a shadow shield, the reactor would provide all power for the mission. Electrical power conditioning equipment would fill the rest of the spoke.

The crew would live in the 12 meter long x 3.8 meter diameter Mission Module. About the size of a large house trailer, the Mission Module would contain the crew quarters, closed-loop life support system, wardroom, and gym.

A de-spun Survey Pallet would carry the planetary encounter cameras, a large reflecting telescope, radiometers, and the Earth communications antennas. The survey instruments would also be used after passing Mars to survey the inner Asteroid Belt.

The hub would provide a docking port for the CRM, airlock, the de-spun Survey Pallet, storage, and external storage for planetary probes.

This model shows two small landers in aeroshells, and a larger probe designed to capture a small surface sample, and rocket it back to the passing mother ship. The CRM would undock from the de-spun ship, rendezvous and capture the sample, then return.

The Propulsion Module is based on an S IV-B; same diameter, but shorter. A modified Apollo Service Propulsion System would be mounted in the aft end.

The Model

The Command Module is modified from the 1/200 scale AMT Man-In-Space kit, but the Retro Module is scratch built, as I wanted to get rid of the Block I details and needed a shorter module. I cut the RCS thrusters from the AMT Service Module, then added them and new styrene radiator panels to the RM. The CM is covered with Ultra Bright Bare Metal Foil, the RM with aluminum BMF.

The rest of the model is built from Plastruct tubing and hemispheres, ¼-inch aluminum tubes, one-inch diameter PVC pipe, and styrene featured sheet. The hub and modules are painted gloss white. The Propulsion Module is painted similar to the Saturn V in black and white, with gold foil on the ends.

The Survey Module is built of basswood, brass and aluminum tube, with the antenna made from a Solo drink lid bubble. Copper candy foil models the multi-layer insulation.

The SNAP 8 reactor and radiator are brass and styrene, and are painted flat black. The planetary probes are cones turned from dowels on a lathe, then covered with gold foil. Paper decals were made on a color printer.

Sources:

• * Ordway, F. I., et al; "EMPIRE - Background and Initial Dual-Planet Mission Studies"; IAA-90-632; 11 October 1990
• ** Parker, J. F. and West, V. R.; Bioastronautics Data Book, 2nd Edition; SP-3006; NASA; 1973; pages 601 - 609
• Davis Portree; Humans to Mars - Fifty Years of Mission Planning; NASA SP-2001-4521; 2001