Those who participated in the STAC presentation already know this, but perhaps some of you, like me, had not heard. It is currently proposed that on the lunar landing mission the first two hours on the lunar surface will be devoted to spacecraft systems checks and launch preparations which, for all practical purposes, simulates the…
Category: Lunar ascent
Ascent newsletter
This memo is to report several interesting things regarding lunar ascent, both nominal and after a descent abort….
Some alternate ways of figuring out where the LM is on the moon will be available
For some months we have been concerned with the problem of determining the LM’s location after its landing on the lunar surface. This information is essential in order to do a decent job of Ascent targeting and, in fact, a significant error can even influence crew safety. Primary modes already implemented in the Control Center/RTCC…
Manual Ascent revisited
On July 2 we had another meeting regarding Manual Ascent. As I have pointed out previously, the consensus is that the crew should have an excellent chance of achieving a safe orbit by manually steering the LM from the lunar surface if they have a rate command attitude control system by using the horizon view…
PGNCS operations while on the lunar surface
During our March 27 Lunar Surface Mission Techniques meeting I think we finally settled how we think the PGNCS should be operated. How many times have I said that before? This memo is to broadcast a few new items that might be of general interest….
The Apollo rendezvous can be shortened by 2 hours
As you no doubt are aware, there is a movement afoot to shorten the Apollo rendezvous by 2 hours. This would be done by eliminating the CSI and CDH maneuvers and executing TPI about ½ hour after insertion. I thought the reason this was being considered was to reduce the crew’s workday, which has been…
Let’s drop one of the lunar surface RR tests
During our review of the G Mission Lunar Surface Mission Techniques Document on April 10, we came to a conclusion which may interest you. It deals with the need, or really lack of need, for the crew to do some things that are in the current flight plan. Specifically, in the crew LM timeline, we…
LM rendezvous radar during Ascent is about to go over the brink.
It turns out providing justification for obtaining LM rendezvous radar data during Ascent from the lunar surface is as difficult as getting the data itself. This memorandum is to let you know that unless some sharp cookie comes along with sufficient justification we ain’t gonna get it!…
Does the landing radar mess up?
This memorandum is to request that you look further into the business of how the use of landing radar observations in the spacecraft computer during descent influences the onboard determination of the final landing point. Hopefully, the landing point is essentially fixed prior to processing of the landing radar data but that may not be…
CSM orbit determination using the LEM radar
Apparently it is planned to use the LEM radar while that spacecraft is sitting on the lunar surface to determine the CSM’s orbit. I am told that the radar angle data accuracy is so poor it will not even be used; the command module’s orbit determination will be carried out with range and range rate…