See list belowAUG 8 196767-FM-T-58FM/Deputy ChiefVHF ranging by CSM for ascent monitoring
1. Attention everyone!! As far as I can tell, everyone wants to get that VHF ranging device on the CM and there's a big effort going on right now to put together the proposal and justification for it. Most attention to date has been given to its use for rendezvous. It is obvious that it should be extremely valuable in saving RCS fuel and, doggone it, just helping the crew figure out what's going on during the braking maneuvers. The thing I want to make sure everyone knows is that this device also has the potential for getting us out of another problem that may be even more serious. And that is lunar ascent monitoring for switchover from PNGS to AGS.
2. Current planning calls for using the LM radar to obtain range rate (CM cs. CSM) data which, when combined with the MSFN, permits the ground to evaluate performance of the two systems. But the LM radar data is going to be hard to get. Reacquisition is almost certainly going to be required during powered flight and assistance from the LM computer is going to be tough to provide — even if the crew has time to fool with it.
3. Transferring this task to the relatively inactive CM via the VHF ranging could really bail us out if it can to the job—and it provides further justification for the VHF ranging as if that were needed!!