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….
Category: Lunar surface abort
Spacecraft computer program – things dealing with lunar descent and aborts from it
I spent an interesting morning at MIT on May 16 with George Cherry, Dan Lickly, Norm Sears, and Craig Schulenberg talking about Luminary how it works and some things that really haven’t been defined yet. It primarily dealt with lunar descent and aborts from lunar descent….
Lunar lift off shall be planned at discrete times only.
During our December 21 Ascent Phase Data Priority meeting we concluded that a continuous launch window for lift off from the lunar surface is not a requirement. That is, all mission planning, procedures and program development associated with the nominal lunar landing mission should be based on the assumption that one or more discrete lift…
The LM can handle big Descent plane changes but required protection against APS abort fuel depletion
We have recently verified that the LM has a substantial capability to translate out of its initial orbital plane during powered Descent at very little cost. That is, whereas previously a limit of 0.3° had been quoted, it now appears that 1° or more is probably possible without effecting the performance of the guidance equations,…
Manual Steering for LM Ascent
Over the years various groups have attacked the problem of if and how the crew can manually steer the LM back into orbit from the lunar surface. These studies were started before GAEC was even selected to build the LM and some analysis is still going on to define the optimum pitch attitude profile, which…
“Any time” LM lift off is an unnecessary constraint
No big deal, but I’d just like to point out that I don’t agree with something in the memorandum to TA/Director of Science and Applications, dated March 19, 1968, subject: Operational constraints for the fourth lunar landing mission, which you signed. It stated in part, “It is the opinion of the Flight Operations Directorate that…
Ascent with busted guidance and control systems
On June 11 we had a Mission Techniques meeting to discuss manual ascent from the lunar surface. The term manual ascent, though, is somewhat misleading since most of our discussion had to do with how the guidance systems should be operated if certain of its components failed prior to ascent. In summary, I think everyone…
How we will handle the effect of mascons on the LM lunar surface gravity alignments
What do we do if one of those big damn lumps of gold is buried so near the LM that it screws up our gravity alignment on the lunar surface? Without exception, the calculations of all the various far-flung experts predict that mascons should have no significant effect on our lunar surface gravity alignments. In…
Descent Aborts and subsequent Rendezvous Mission Techniques
On April 28, 1969 we reviewed the Descent Aborts and subsequent Rendezvous Mission Techniques with the crew and the rest of the world. I think most of this is quite complete and agreeable to everyone concerned, with one major exception. I was shocked and ashamed to find that I had badly misunderstood the situation regarding…
Descent Data Select procedures are finalized
On July 7 and 8 we held a final review of the Data Select procedures and Flight Controller interface during the Descent phase of the lunar landing mission. This lengthy memo is to describe briefly some of the items discussed, all of which are being thoroughly documented before the flight….