During our discussion at MIT last week, the question came up as to whether it is necessary to have trajectory integration techniques in the LCG for the trans-earth phase of the mission as well as the lunar phase. The argument is that if we are serious about using the LM descent propulsion system to back…
Category: Transearth coast
Apollo spacecraft guidance navigation modes currently planned for AS-503 and AS-504
I am afraid there is a bit of confusion as to what navigation modes are being provided in the AS-503 and AS-504 Apollo spacecraft computer programs. I am sure I have contributed to this confusion myself, and the purpose of this memorandum is to try and clear it all up….
Prelaunch DAP initialization
During our review of the lunar landing GSOP’s, the question of prelaunch DAP initialization was brought up. As far as I can see, there is no use for the DAP until after TLI, isn’t that right? For example, the contingency orbit insertion maneuver does not use the DAP nor does CSM guidance of the S-IVB….
Data Priority meetings schedule
In order to get a little bit more orderly in our conduct of the Trajectory Control Data Priority business, it’s evident that we must schedule meetings on a pre-established, periodic basis. Accordingly, the Ascent and Descent meetings will take place on alternate Tuesday afternoons; Rendezvous meetings will be held of Wednesdays, one mission in the…
Spacecraft computer program orbital integration
This is just another little golden nugget for your files….
Lunar Reentry Mission Techniques meeting – March 21
On March 21 a small group of us ???? ??????? the logical flow charts TRW produced based on our ??? Lunar Reentry Mission Techniques meeting a couple of weeks ago. A couple of things came up that I should probably pass around….
April 9 Lunar Reentry Mission Techniques meeting
Almost the entire April 9 Lunar Reentry Mission Techniques meeting was spent in discussion of the second and third midcourse correction maneuvers made on the way back from the moon. Ron Berry presented some really interesting data which I think gives us an insight into the character of these maneuvers needed to assure the techniques…
No special visual reference will be provided for the final transearth midcourse correction maneuver
On May 7 we reviewed the need for an RTCC program change to provide a special visual reference for the crew during the last transearth midcourse correction maneuver on a lunar mission. We concluded it is not needed and that no new programming or displays are required….
Transearth midcourse maneuvers are getting easier and cheaper all the time
On June 6 we had a Transearth Midcourse Maneuver Mission Techniques meeting at which we discussed implementation of the philosophy as described in my June 3 memo. The technique proposed, you recall, involves making a number of small RCS burns using the SCS, solely for the purpose of corridor control. I have discussed this with…
Need to know some transearth midcourse correction (MCC) ΔV costs
I think we have pretty well established the transearth MCC maneuver philosophy now. As you know, it involves making small corridor correction maneuvers as their need becomes apparent. Nominally they will be made with the RCS propulsion system utilizing the SCS control system. Very large attitude errors may be tolerated during the burn….