There is some concern about the capability of the AGS to safely perform an abort from hover without a PGNCS alignment during the Hohmann transfer. This concern stems from the results of Monte Carlo analyses which indicate that the mean minus three sigma for perilune altitude of an AGS controlled abort from hover is less than 30,000 feet (the safe orbit limit), and from single error analyses which indicate that an initial misalignment slightly larger than three sigma results in an unsafe orbit……
Category: Mission phases
PGNCS Alignment During Hohmann Transfer
The attached IOC presents an analysis which estimates the increase in the probability of an unsafe AGS abort if the PGNCS alignment during Hohmann transfer is not performed. The analysis shows that given that PGNCS fails, the probability of an unsafe AGS abort from hover is increased by less than 0.001……
“D” Rendezvous Mission Techniques meeting of July 22
We cleaned up a lot of stuff at the subject meeting. Attached are updated “Ground Rules, Working Agreements, and other things,” and another list of open items to be discussed at our next meeting currently scheduled for September 6, 1968, or whenever the crew is available after that….
“D” MISSION RENDEZVOUS NAVIGATION MISSION TECHNIQUES PANEL
Objectives of the panel are to establish the following rendezvous navigation mission techniques……
“D” RENDEZVOUS MISSION TECHNIQUES OPEN ITEM LIST
July 25, 1968…
Procedure for LM aborts immediately after landing are terrible!
Clarke Hackler of Guidance and Control Division uncovered a rather alarming situation which we’ve discussed a little at our Descent Abort Mission Techniques meetings. He briefly states the problem quite nicely in the attached memo, which I thought should be brought to your attention….
Requirement for pre-PDI IMU alignment has been deleted
After extensive Mission Techniques Panel review, it has been established that a PGNCS IMU alignment immediately prior to Powered Descent is not required for any reason. It is, in fact, undesirable at this critical time in the mission when lighting conditions couldn’t be worse (local high noon!)…
Procedures needed for the AS-503 TLI maneuver
This note is to back up our telephone conversation (2/5/67) in which I requested you to prepare our recommendation as to how the AGC should be used during the simulated translunar injection maneuver on AS-503. It’s certain the crew will want to monitor the progress of this large SIVB maneuver, even though it’s controlled by…
Lunar Landing Guidance and Control Modes
Gentlemen:…