NASA Office of Logic Design

NASA Office of Logic Design

A scientific study of the problems of digital engineering for space flight systems,
with a view to their practical solution.

Apollo Software and Related Items

Hugh Blair-Smith from the MIT Instrumentation Laboratory
Hugh Blair-Smith from the MIT Instrumentation Laboratory
discussing his software at the 2004 MAPLD International Conference.

Some of the documents on this page are posted here courtesy of MIT and are for the use of researchers, engineers, historians, and interested readers.  Thus, not all documents are not in the public domain and distribution must be approved by MIT. 

I have organized the documents, extracted abstracts, and will maintain them and improvements to the quality of documents.  Please send comments and suggestions to


LEM Guidance Computer Programs to be Supplied by MIT

David G. Hoag
November 1965
AG: 937 -65

Introduction (excerpt)

This document is being submitted by MIT for approval by the Apollo Guidance Software Control Panel.  The document defines the test programs which will be supplied by MIT to support checkout of the LEM flight vehicle system, GAEC radar integration tests, and GAEC flight control integration tests.  These programs will be incorporated into the basic Block 2 computer service program designated as AURORA by MIT.  It was agreed at NASA Coordination Meeting # L18A and GAEC/MIT Checkout Work Group Meeting #14 that these programs, which were outlined in the above meetings, would satisfy all of the LGC program requirements for the above checkout and integration tests.

Apollo Guidance Software Development and Validation Plan

The Guidance Software Validation Committee
NASA Manned Spacecraft Center
October 4, 1967 

Purpose and Scope
     This report documents the general plan for verification of the Apollo flight software. The plan defines the necessary steps for control and verification of the software to be contained in the Command Module Computer (CMC), LM Guidance Computer (LGC), and the computer in the LM Abort Guidance Section (AGS). Included in this plan are the software development; software verification; simulation model control; software review, approval, and change control; and representative schedules. The general plan is summarized, and conclusions and recommendations are presented in Section 2.
     The scope of this plan is limited to the existing Apollo software procedures and status. The AGS software procedures differ from those for the CMC and LCC in a minor respect but this plan is general enough so that it, applies to all three Apollo software development efforts. Specific differences between the AGS software development and the CMC and LCC software development will be noted only when it is deemed necessary for clarification .
     Software, as defined in this report, means only the contents of the computer which is more normally called the computer program. In the context of this report, qualification means that it has bean demonstrated by the contractor that the software meets the requirements set forth in the specifications and verification means that it has been demonstrated independent of the software contractor that the software meets the requirements set forth in the specifications. Software development is included in this plan to identify the development procedures necessary for delivery and Verification of a program.

A Comprehensive Digital Simulation for the Verification of Apollo Flight Software

F. K. Glick and S. R. Femino
January 1970

The flight software for the on-board Apollo Primary Guidance, Navigation and Control System provides attitude and trajectory control, recursive navigation, targetting, inertial subsystem moding and alignment, prelaunch checkout, crew interaction and telemetry processing for each spacecraft. To develop and flight qualify this complex software package, an all-digital, instruction-by-instruction simulation of the on-board computerís operation has been implemented, along with a powerful set of software diagnostics. This computer simulation is coupled to a comprehensive digital simulation of the computerís environment, including the sensor systems. The simulator is described and design considerations, advantages and limitations are discussed. A simulated powered flight maneuver is compared with telemetry obtained during the actual performance of the maneuver in flight. The telemetry data revealed a potentially significant effect which had not been modeled. As a result the environment simulation was upgraded to more accurately represent the flight environment.

An Automated Documentation Technique for Integrating Apollo Crew Procedures and Computer Logic

J. C. Dunbar, R. A. Larson and P. T. Augart
May 1966 

This paper describes a document devised by MIT, which relates 1) on board computer activity, 2) related ground computer activity, and 3) sequencing of airborne systems intimately related to the guidance and navigation (G&N) system, to human operator activity during the Apollo Mission G&N operations. The document serves as a tool for computer programmers, provides a testing device for evaluating mission operations in the various simulators and also serves as a training device. The crew checklist used to define G&N and related airborne system operating procedures is in a form that could be directly used for flight operations. The documentation technique evolved allows rapid information retrieval and updating. Various forms of the data can be extracted for use in mission planning, computer programming, operations analysis, or crew training.

The Compleat Sunrise being a description of Program Sunrise (Sunrise 33 - NASA DWG# 1021102)

R. Battin et al.
September, 1964

Note: Fix page 1, upside down.

SUNRISE (SUNRISE 33 - NASA DWG # 1021102) is a computer program which has been prepared for the Apollo Guidance Computer and is intended for operation with, at least, Apollo Guidance and Navigation Systems 4 through 7. The objectives of SUNRISE are to:
  1. provide the groundwork in terms of input/output, control and utility programs for all subsequent Apollo Guidance Computer programs;
  2. provide the necessary tools for proofing guidance systems 4 through 7;
  3. demonstrate the efficacy of an all-digital simulation as a checkout tool; and
  4. demonstrate rapid turn around time for manufacture and checkout of core ropes.

YUL System - Pass 0

Hugh Blair-Smith


Luminary 131

December 19, 1969

Apollo LUMINARY 131 (1C)
Program Source Code Listing


Control of Flight Software Development Costs

March 11, 1971


Software Is Expensive
Schedules Are Difficult to Predict and to Meet
Cost and Schedule Overuns Are Common

Future Programs Will Be 10 Times Larger Than Past Programs
How Can Software Costs Be Kept Under Control?

Colossus Assemble Revision 249

October 28, 1968



Charles A. Muntz
April 1965

A description is given of the AGC/LGC (Apollo and LEM  Guidance Computers) algebraic interpreter, a language in which Apollo Mission computer programs may be conveniently prepared.


Apollo Documentation Master Page

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Last Revised: February 03, 2010
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