Post-insertion alignment is lower priority than rendezvous navigation

It has been agreed that it is more important for the LM to obtain rendezvous navigation tracking data than to complete the platform realignment after insertion into orbit if problems occur which prolong it. The point is, an accurate CSI maneuver is vital but it is recognized that bad angle data does not substantially degrade that solution. Thus, even though the lunar surface platform alignment may not be red hot it should be adequate to support the rendezvous navigation; if the crew experiences difficulty in realigning, they should terminate that effort to insure they get an adequate amount of rendezvous radar data. Specifically, they should complete or terminate the P52 by 30 minutes before CSI. If they do fail to complete the alignment, they should add one into their timeline immediately after CSI and depend on the CSM for their plane change targeting.

I would like to emphasize that this is a contingency procedure since everyone anticipates that adequate time has been provided to do this alignment.

Terms & Abbreviations

CSI

Co-Elliptic Sequence Initiation. One of the maneuvers performed by the LM after ascent from the lunar surface to rendevouz with the CSM.

CSM

Command-Service Module.

LM

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.”