Spacecraft computer program flow chart status

1. Just a note to you cats who are interested in flow charts for the spacecraft computer programs. MIT has had a small group headed by John Venize who have done what appears to be an excellent job of establishing standards to be followed in the development of flow charts. A group of SDC people have been given the job of taking the program listings and rough flow charts from the programmers and turning those into the final product. We were given a schedule defining when various portions of the Sundisk earth orbital command module computer programs will be completed. It should be finished no later than November 17. Substantial portions will be finished sooner than that, of course, available for distribution. It has been our goal to do those processors of most immediate interest first. Anyone interested in the actual schedule should get in touch with Jack Williams of the Flight Software Branch.

2. I really think we’ve got this thing moving well now (finally!) and will be interested in your comments. It was our intention to set up some system of discrepancy reporting in which we will encourage you to participate. The intent is to inform MIT people of differences between the program listing and the flow charts and the GSOP’s such that they may be corrected. This should also provide an incentive for the programmers to thoroughly check the flow charts before release, since we are requiring that they sign off on them as being responsible for their accuracy. Naturally, we intend to execute any programmer whose flow charts contain a significant number of errors.

Terms & Abbreviations


see Guidance System Operations Plan

Guidance System Operations Plan

The GSOP was essentially the specification for how the guidance computer and its software where required to work for a specific mission. Many of GSOP’s are available online including the GSOP for the cancelled AS-207/208 mission


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.