See listFEB 23 196767-FM1-20FM/Deputy Chief, Mission Planning and Analysis DivisionStar/landmark navigation exercise preflight planning
A call from Mr. C. C. Kraft the other day drew my attention again to the spacecraft guidance system navigation tests planned for the AS-503 mission. He had received indications that the planning for this exer- cise was rather haphazard. Specifically, he recommended that MIT be brought into the mission planning in this time in order to insure their satisfaction, since they are probably as much or more concerned than any other organization in evaluating performance.
This memo lists a number of jobs which need to be done. Perhaps they should be coordinated and formalized by ATSO. Specifically:
1. The Mathematical Physics Branch, working with MIT through the Flight Software Branch, should establish precisely the mission planning requirements for carrying out the star/landmark and star/horizon obser- vations during high altitude orbits such as planned for AS-503. These requirements should include the identification of stars and landmarks to be used and the lighting conditions which are necessary. Since it is currently planned to fly the AS-503 mission with the AS-278 programs, you are reminded that actual update of the state vector onboard the spacecraft may not be possible. As a result, some thought must be given as to how the postflight data processing shall be carried out. It would be disastrous if, as a result of lack of foresight, insufficient data were collected during the exercise, making it useless. Since there is a good possibility of carrying out this type of exercise after the AS-504 program has been completed, some thought should also be given to what modifications to the exercise would be called for in that event.
2. Obviously, the Mission Analysis Branch must work closely with the people on the above task, giving proper emphasis in the mission design to the requirements for this exercise. They will certainly conflict with other mission constraints, and the compromises which will be necessary must ultimately be MAB's responsibility to identify and make.
3. I suppose it is up to the Mathematical Physics Branch to make sure that they and/or MIT have the proper programs prepared to carry out the postflight analysis. This preparation, of course, includes provision of the capability of accepting the data as it will be provided to them after the mission, as well as selection and formulation of program output formats most suitable for analyzing the results. It is to be emphasized that we will be looking for answers relatively quickly, since I anticipate the missions will start to follow one another fairly rapidly by the time this exercise is carried out and little time will be available to modify the spacecraft computer programs if that is found to be neces- sary.
A task assignment, in the TRW format, should be prepared for transmit- tal to MIT for whatever work it is we feel they should do. For one thing, MIT should be requested to formally submit to us their post- flight data requirements.
It seems to me the most important thing right now is to insure that the mission planning is compatible with the needs of this exercise. Since the mission plans for the carious Apollo missions are in such a state of flux, I would recommend that wherever possible the exercise be planned independent of the specific mission such that it could be inserted as a package into whatever missions it is ultimately felt it should be included.
- Feb 28, 1969 – There will be no VHF ranging data collected while tracking the LM on the lunar surface (3.3σ)