F Mission Techniques – LM Checkout

See list attachedDecember 9, 196868-PA-T-270APA/Chief, Apollo Data Priority CoordinationF Mission Techniques – LM Checkout

On December 6 we had our first F Mission Techniques meeting dealing with pre-DOI activity. It resulted in a lot of things I never expected, since I thought the timeline and procedures for LM checkout and CSM landing site tracking were pretty well organized and acceptable with just minor tune-up. At this meeting we really shook up the world and are now looking into substantial changes in overall concept as well as changes to the detailed techniques. The two most significant proposals under consideration now involve the following:

a. There are good reasons – and a strong desire on the part of the crew – for manning and checking out the LM prior to putting on their bunny suits (PGA's). The significance of this as I understand it is that the crew feels they can perform their tasks much easier with- out the suits on – including moving from one spacecraft to the other quickly and easily and then suiting up at some convenient time integrated in with the other activity just prior to DOI.

b. Everyone is now seriously looking into the benefits and dis- advantages of scheduling a period of LM checkout prior to DOI Day. The idea is to see if it is possible to shorten DOI Day by manning, powering up and checking out many of the LM systems, and then powering it down again prior to LOI (actually before the last translunar midcourse correction) or immediately after LOI₂ before the rest period. Of course, it must be determined that checkout carried out at this time need not be repeated after powering down the LM and that the time and energy spent during this earlier period is not too expensive. It must be emphatically stated that our decisions must be based on G mission constraints since they may be tougher to meet than the F mission. The point is that we certainly do not want to set up a special technique just for F since one of our primary objectives is to use F as a dress rehearsal for G.

If we schedule a pre-LOI period for LM activation and checkout, the configuration on DOI Day will be:

a. LM will be pressurized

b. Drogue and probe will be stowed in the CSM (any structure or c.g. problem for LOI?)

And the following system checks will have been made:

a. S-Band steerable has been checked

b. VHF B simplex checked

c. COAS and AOT lighting checked

d. LR checked

e. LM S-Band (PRN) ranging DTO accomplished

f. Cabin regulator checked

g. DPS throttle checked

h. Oxygen purge system checked

i. RCS cold firing (requires LGC and IMU powered up)

j. Gimbal drive test (requires LGC and IMU powered up)

k. PGNCS gyro drift checked

l. PIPA gyro drift checked

m. CES rate gyro checked

n. LGC E-memory dumped and checked – and reloaded if necessary

Again, the major reason for doing this is to reduce the pre-DOI timeline since on both F and G the DOI Day has grown excessively long. Speci- fically, the current timeline provides about 10 hours between wake-up and the DOI maneuver. More than one-half the day is gone before they even start doing anything.

So you see quite different than my naive pre-meeting impression, we have a lot of things to do to get this thing squared away, but before we can even do that we have to get some fairly significant decisions on the two items noted above. Of course, we must do enough work to supply the data required to get these decisions, unless someone wants to arbitrarily choose our course of action. We intend to get together again on Friday, December 13 to continue our deliberation. In the meantime, we are hoping to get some opinions from around the country whether this is an insane approach or not.