Tindallgrams

MIT currently has plans for supplying a number of different modes for using their basic orbit determination program. (MIT calls this process “navigation,” so I will, too.) These modes differ in that there is a variety of types of observational data used during different mission phases.

In our attempt to simplify the AS-504 spacecraft computer program, we are reviewing the overall situation to determine that no unnecessary modes are included. For example, there is no need to perform orbit navigation while in earth orbit for the lunar mission or any recognized contingency situation. This particular orbit navigation mode was to utilize star/landmark observations along with other earth orbital service routines and special initialization capabilities to determine the spacecraft state vector prior to the translunar injection maneuver. Since this program is not required for the lunar mission, MIT will be directed not to include it in the AS-504 program. Since we do not intend to implement any programs especially for AS-207, unless directed otherwise, it will be dropped from the AS-207 computer program as well, which means that the CSM will not have the capability of determining its own orbital elements during that mission.

Accordingly, it will not be possible to satisfy that mission objective as referenced in TRW document 2132-H008-R8-000, “Mission Requirements for Apollo Spacecraft Development Mission AS-207/208” dated March 7, 1966, classified Confidential.

Terms & Abbreviations

504

see AS-504

AS-207/208

AS-207/208 (also known as AS-278) was to have been the first test of the LM in Earth orbit. It was also to have be a dual mission with the command and lunar modules launched on separate Saturn 1Bs. The mission was cancelled after the Apollo 1 fire and the Saturn 1Bs were used to launch Skylab 3 (AS-207) on July 28, 1973 and Skylab 4 (AS-208) on November 16, 1978. The LM was first tested by Apollo 5 in January 1968.

AS-504

Before the Apollo 1 fire, the mission referred to as AS-504 was originally scheduled for December 1967. AS-504 eventually launched as Apollo 9, March 3 1969.

CSM

Command-Service Module.

MIT

Massachussets Institute of Technology. In these memos, MIT is shorthand for the MIT Instrumentation Laboratory, created and led by avionics pioneer Charles Stark Draper. It is now known as the Charles Stark Draper Laboratory and became independent of MIT in 1973.