luke strawwalker
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Here's an interesting study from the late 60's- detailing the MEM, or Mars Excursion Module. This was essentially an Apollo capsule upscaled to 31.5 foot diameter, and totally reworked on the inside to incorporate a small ascent module with staged tanks in the upper center portion of the vehicle, surrounded by landing fuel tanks and equipment around a toroidal living area and laboratory for Mars surface operations. The vehicle had a single high-thrust landing engine under the heatshield in the center of the vehicle. Deorbit burn to Mars entry was by a solid motor retropack (similar to how Mercury capsules retroed back to reentry) which was jettisoned prior to entry interface. After Mars entry, the vehicle would jettison its heat shield and either deploy a ballute or supersonic parachutes to slow down, then jettison those and switch over to propulsive descent and landing, with a 2 minute hover capability. Landing was via six build in landing legs which conformed to the shape of the underside of the capsule. Crew size was for four men, for either 4 or 30 days. Upon Mars departure, the crew entered the small ascent cabin in the upper portion of the MEM, which then blasted off from the lower portion which was left behind, with the living space, lab, equipment, etc. The ascent stage would burn through its first stage propellant tanks, which would jettison as they emptied, and switch over to its second stage propellant tanks (using the same engine-- only the tanks were jettisoned like the ET). The vehicle would enter Mars orbit and return the crew to the awaiting transit spacecraft for return to Earth, and the ascent stage would be jettisoned. The MEM remained unmanned during its transit to Mars, as the crew were housed in the transit spacecraft.
This study outlines a series of test flights, to simulate the heat shield and abort conditions at Mars using Earth's extreme upper atmosphere to simulate the low density Mars atmosphere, and booster rockets to lift the MEM to those regions and accelerate it to the requisite speeds to simulate the Mars entry conditions of the specific tests. Test vehicles, depending on the nature of the test, ranged from uprated Saturn I's, to two-stage Skylab style Saturn V's (launched manned and unmanned) to Saturn S-IC first stages from Saturn V used as a single stage vehicle to launch the MEM to high altitude suborbital tests, to a new SRM powered "Super Little Joe II" designed not to the 154 inch diameter Apollo Command Module, but to the 31.5 foot diameter MEM... sort of an "uber Little Joe", which would have been launched out of White Sands. Both unmanned and manned landing tests would have been conducted at White Sands, with the MEM landing propulsively under its own power (if the heat shield were designed to Earth entry standards, which was the recommendation) and also there was a plan for a possible "all up" test mission rehearsal landing the MEM on the moon. There was also a possible plan to do a half scale MEM using an Apollo module, which would be almost perfectly half-scale, adapted to simulate the functions of the MEM (but of course its internal layout would have been markedly different....) this would have been launched unmanned by a single Saturn V to Trans-Mars Injection, and the Service Module would have provided Mars Orbit Insertion propulsive braking. The modified Apollo "MEM half scale" vehicle would have then separated from the SM, and entered Mars atmosphere and performed EDL just as the MEM was designed to do. After a suitable surface stay, the vehicle would then fire its half scale ascent stage back to orbit. Such a mission would be an excellent design for a Mars sample return, if we still had the Saturn V around to launch it!
Anyway, it's an interesting idea-- too bad it never happened. If it had, history might have recorded the first Mars landing in 1982 instead of *maybe sorta someday perhaps hopefully might kinda think about it study and make plans to maybe do it* in about 30 years or so FROM NOW...
Later! OL JR
View attachment NASA Study Summary- Definition of Experimental Tests for a Manned Mars Excursion Module.txt
This study outlines a series of test flights, to simulate the heat shield and abort conditions at Mars using Earth's extreme upper atmosphere to simulate the low density Mars atmosphere, and booster rockets to lift the MEM to those regions and accelerate it to the requisite speeds to simulate the Mars entry conditions of the specific tests. Test vehicles, depending on the nature of the test, ranged from uprated Saturn I's, to two-stage Skylab style Saturn V's (launched manned and unmanned) to Saturn S-IC first stages from Saturn V used as a single stage vehicle to launch the MEM to high altitude suborbital tests, to a new SRM powered "Super Little Joe II" designed not to the 154 inch diameter Apollo Command Module, but to the 31.5 foot diameter MEM... sort of an "uber Little Joe", which would have been launched out of White Sands. Both unmanned and manned landing tests would have been conducted at White Sands, with the MEM landing propulsively under its own power (if the heat shield were designed to Earth entry standards, which was the recommendation) and also there was a plan for a possible "all up" test mission rehearsal landing the MEM on the moon. There was also a possible plan to do a half scale MEM using an Apollo module, which would be almost perfectly half-scale, adapted to simulate the functions of the MEM (but of course its internal layout would have been markedly different....) this would have been launched unmanned by a single Saturn V to Trans-Mars Injection, and the Service Module would have provided Mars Orbit Insertion propulsive braking. The modified Apollo "MEM half scale" vehicle would have then separated from the SM, and entered Mars atmosphere and performed EDL just as the MEM was designed to do. After a suitable surface stay, the vehicle would then fire its half scale ascent stage back to orbit. Such a mission would be an excellent design for a Mars sample return, if we still had the Saturn V around to launch it!
Anyway, it's an interesting idea-- too bad it never happened. If it had, history might have recorded the first Mars landing in 1982 instead of *maybe sorta someday perhaps hopefully might kinda think about it study and make plans to maybe do it* in about 30 years or so FROM NOW...
Later! OL JR
View attachment NASA Study Summary- Definition of Experimental Tests for a Manned Mars Excursion Module.txt