Results of the October 8 Apollo Spacecraft Software Configuration Control Board (ASSCCB) meeting

See list attachedOctober 16, 196868-FM-T-225FM/Deputy ChiefResults of the October 8 Apollo Spacecraft Software Configuration Control Board (ASSCCB) meeting

In this memo I will briefly describe some of the highlights of the subject meeting:

1. There was a long discussion regarding the effects of CDU tran- sients on AGS alignments while on the lunar surface. It appears there are some fairly simple procedures for making sure unacceptable errors are not introduced into the system. A matter that was not discussed was what sort of problems we can have in the AGS alignment while on coasting flight where spacecraft attitude changes make checking very difficult. We will have to pursue these matters in the mission techniques development.

2. There were four PCR's approved that I would like to call your attention to. They are:

a. PCR 546 (LUMINARY): Delete V50N25 display in P68. Crew must insure a stable LM before “proceed” response to V06N43. The V50N25 dis- play is not necessary. Attitude storage can be done after crew response to previous V06N43.

b. PCR 547 (LUMINARY): Delete V37N57 display at end of P68 and add “Do final automatic request terminate routine (R00).” Chapter 4 incorrectly shows P68 terminating with V37N57.

c. PCR 551 (LUMINARY): Reduce normal maximum commanded rate from 20°/sec. to 14°/sec. since maximum commanded rate of ACA normal scaling is too high for manual lunar landing. Reduce normal and fine scaling by a factor of 7 for the CSM-docked case since normal and fine scaling of ACA are too high for manual lunar landing.

d. PCR 552 (COLOSSUS): Add P22 assumption to read as follows: The first mark obtained by this program cannot be the landing site. Coding in P22 cannot accept landing site as first mark.

3. Since all of DPS guided burns on the currently planned missions terminate at 40% thrust or less, it was decided to place the DPS tailoff for 40% in memory rather than full thrust.

4. MIT requested that we approve a change (PCR 494), which would put the LGC value of landing site location (RLS) on the ascent and descent downlink format. I am not sure why they want this unless it is for systems testing purposes. Note: We have no capability of reading it out in the control center in real time right now.

5. PCR 250 to put SPS mass flow rate (M DOT) into erasible memory of COLOSSUS 1A was approved.

6. PCR 245 to permit use of planets in P23 and R53 was approved for COLOSSUS II but will not be in COLOSSUS 1A.

7. Just so there is no misunderstanding on this, MIT has been directed to delete the rendezvous radar acquisition routine (R29) from the LGC descent program (P63) completely.