Apollo 11 LM 5 computer words printed log of Apollo 11 landing telemetries - jumpjack/Apollo11LEMdata GitHub Wiki
In january 2022 the VirtualAGC team discovered a precious, ancient document: the printing of telemetries sent by the onboard computer (Guidance Computer) of the Lunar Module 5 ("LGC", LM Guidance Computer), the descent stage of Apollo 11. Its title is "Apollo 11 LM-5 computer words", and is made of 71 pages, structured as follows:
- 1-10: Registers (102:31:25 - 102:48:09)
- 11: ALPHAR, ALPHAQ, CSMMASS, LMMASS (102:45:01 - 102:46:45)
- 12-13: TLRRNG, LRRNG DP, CDUYLRR, CDUZLRR, CDUXLRR (102:38:09 - 102:46:33)
- 14: TTF/8, DELTAH, LSVECX, LSVECY, LSVECZ, LSPOSX, LSPOSY, LSPOSZ (102:17:49 - 102:39:19)
- 15-23: TLAND, DDPSTHR, VTHACCEL, TTOGO, CMDECA (102:32:27 - 102:48:37)
- 24-30: FAILREG 0,1,2 , RSBBQ 0,1 , CADRFLSH 0,1,2 (102:36:09 - 102:46:13)
- 31-33: Channels 30-33 (102:17:17 - 102:49:20)
- 34-42: Channels 11-14 (102:17:17 - 102:49:20)
- 43: Flagwords 0-3 (102:17:17 - 102:49:20)
- 44:45: Flagwords 4-7 (102:17:17 - 102:49:20)
- 46: DAPTAB+11d, IMODES30, IMODES33, RADMODES (102:17:17 -102:18:58)
- 47-48: Flagwords 8-11 (102:17:17 - 102:49:20)
- 49-51: DAPBOOLS (102:17:17 - 102:49:20)
- 52-69: CDUX, CDUDX, CDUY, CDUDY, CDUZ, CDUDZ, RRCDUS, RRCDUT (~102:30:00 - 102:45:48)
- 70,71: Channels 30-33 (102:17:18.070 - 102:38:58.070)
Telemetries grouped by topic
Alphabetical list (name/page)
| ALPHAQ | 11 |
|---|---|
| ALPHAR | 11 |
| CADRFLSH 0 | 24 |
| CDUDX | 52 |
| CDUDY | 52 |
| CDUDZ | 52 |
| CDUX | 52 |
| CDUXLRR 12 | |
| CDUY | 12 |
| CDUYLRR | 12 |
| CDUZ | 12 |
| CDUZLRR | 12 |
| CMDECA | 14 |
| CSMMASS | 11 |
| DAPBOOLS | 49 |
| DAPTAB+11d | 46 |
| DDPSTHR | 14 |
| DELTAH | 15 |
| FAILREG 0 | 24 |
| IMODES30 | 46 |
| IMODES33 | 46 |
| LMMASS | 11 |
| LRRNG DP | 12 |
| LSPOSX | 15 |
| LSPOSY | 15 |
| LSPOSZ | 15 |
| LSVECX | 15 |
| LSVECY | 15 |
| LSVECZ | 15 |
| RADMODES | 46 |
| RRCDUS | 52 |
| RRCDUT | 52 |
| RSBBQ 0 | 24 |
| TLAND | 14 |
| TLRRNG | 12 |
| TTF/8 | 15 |
| TTOGO | 14 |
| VTHACCEL | 14 |
Time coverage
Following image shows the coverage of each group of telemetries: almost everyone covers the landing (vertical green bar), but telemetries on page 14 and on page 46; pages 70-71 apparently contain same telemetries of pages 31-33 (channels 30-33):
Telemetries acronyms explanation
This repository of AGC/LGC source code for just Apollo 11 mission can help finding descriptions fot each acronyms without providing too many false positive; for a deeper search in all sources of all version of AGC/LGC source code, VirtualAGCrepository is a better resource.
Alphabetical list and description
| Telemetry name | From page | Possible meaning | Description in paper |
|---|---|---|---|
| ALPHAQ | 11 | Accel about z body axis | |
| ALPHAR | 11 | Accel about Y body axis | |
| CADRFLSH 0 | 24 | Octal address | |
| CADRFLSH 1 | 24 | Octal address | |
| CADRFLSH 2 | 24 | Octal address | |
| CDUDX | 53 | Desired CDU-X | |
| CDUDY | 53 | Desired CDU-Y | |
| CDUDZ | 53 | Desired CDU-Z | |
| CDUX | 53 | CDU-X value | |
| CDUY | 12 | CDU-Y value | |
| CDUYLRR | 12 | CDU-Y at Landing Radar Range "RD"? | Y CDU AT LR RNGE RD |
| CDUZ | 12 | CDU-Z value | |
| CDUZLRR | 12 | CDU-Z at Landing Radar Range "RD"? | Z CDU AT LR RNGE RD |
| CMDECA | 15 | Throttle | Thrt. Output counter |
| CSMMASS | 11 | Mass of CSM | CSMMASS LGC estimat of CSM mass |
| DAPBOOLS | 49 | (see table) | |
| DAPTAB+11d | 46 | (see table) | |
| DDPSTHR | 15 | Descent Power System Thrust? | DPS thrust |
| DELTAH | 14 | Differennce beyween radar measured altitude and LGC calculate altitude | LR-LGC Altitude |
| FAILREG 0 | 24 | Alarm register 0 | |
| IMODES30 | 46 | (see table) | |
| IMODES33 | 46 | (see table) | |
| LMMASS | 11 | Mass of Lunar Module | CSMMASS LGC estimat of LM mass |
| LRRNG DP | 12 | Landing Radar Range for Descent Propulsion? | D.P. LNDNG RADAR SLANT RANGE |
| LSPOSX | 14 | X comp. Landing sit stb mem coord | |
| LSPOSY | 14 | Y comp. Landing sit stb mem coord | |
| LSPOSZ | 14 | Z comp. Landing sit stb mem coord | |
| LSVECX | 14 | X component of speed w.r.t. landing site? | X comp landing sit lunar coord |
| LSVECY | 14 | Y component of speed w.r.t. landing site? | Y comp landing sit lunar coord |
| LSVECZ | 14 | Z component of speed w.r.t. landing site? | Z comp landing sit lunar coord |
| RADMODES | 46 | (see table) | |
| RRCDUS | 53 | Rendevouz Radar Shaft CDU angle | RR SHAFT CDU ANGLE |
| RRCDUT | 53 | Rendevouz Radar Trunnion CDU angle | RR TRUN CDU ANGLE |
| RSBBQ 0 | 24 | Calling address to restart routine | Calling add to restart routine |
| RSBBQ 1 | 24 | Q register content | |
| TLAND | 15 | Calculated future time of landing | Time of landing |
| TLRRNG | 12 | TM OF CDU'S FOR LR RANG READING, R12 | |
| TTF/8 | 14 | Time to phase end | |
| TTOGO | 15 | Time to ignition of descent engine (= to start of PDI) | Time to ign on engine cut off |
| VTHACCEL | 15 | Vehicle accel |
Additional resources
- Link to other formats: https://archive.org/details/apollo_11_computer_words
- High resolution, single JP2 images: https://ia802308.us.archive.org/view_archive.php?archive=/27/items/apollo_11_computer_words/apollo_11_computer_words_jp2.zip