Verification of LGC when powered-up in space

The other day at MIT, when we were discussing the alternate mission AS-278B, the question came up of how the astronaut assures himself that the contents of the erasable memory is as it should be when he first powers-up the computer in space. Since there seemed to be some confusion or uncertainty at MIT, I suppose that situation is the same throughout the universe. We were told, or at least I think we were told, that when first turning on the computer after it has been completely powered-down there is no assurance that the contents of the erasable memory will be the same as it was when powered-down. Since on every manned LM mission the computer must be brought on line from a completely dormant state, some procedure must be established for checking this portion of memory, I suppose. Is anyone within the sound of my voice working on that? In fact, who is supposed to? I guess we ought to ask MIT to do something, and we will.

Terms & Abbreviations


AS-207/208 (also known as AS-278) was to have been the first test of the LM in Earth orbit. It was also to have be a dual mission with the command and lunar modules launched on separate Saturn 1Bs. The mission was cancelled after the Apollo 1 fire and the Saturn 1Bs were used to launch Skylab 3 (AS-207) on July 28, 1973 and Skylab 4 (AS-208) on November 16, 1978. The LM was first tested by Apollo 5 in January 1968.


see AS-207/208

Erasable memory

The Apollo Guidance Computer had a small amount of "erasable memory" analogous to the RAM in a modern computer.


Lunar Module. Earlier it was known as the Lunar Excursion Module and abbreviated “LEM.” Even after the name change, it continued to be pronounced “lem.”


Massachussets Institute of Technology. In these memos, MIT is shorthand for the MIT Instrumentation Laboratory, created and led by avionics pioneer Charles Stark Draper. It is now known as the Charles Stark Draper Laboratory and became independent of MIT in 1973.