[Apollo 11]

Directly from the Personal Collection of Apollo 11 Lunar Module Pilot Buzz Aldrin

FLOWN TO THE LUNAR SURFACE ON APOLLO 11. This checklist sheet details the completion of Rendezvous Radar testing and the beginning of the Abort Guidance System (AGS) calibration, from the personal collection of Lunar Module Pilot Buzz Aldrin, "Dr. Rendezvous" and the first LMP to operate AGS in Lunar landing himself.

Two copies of the Apollo 11 LM Systems Activation Checklist, the Launch Operations Checklist and the Entry Operations Checklist were were carried to the Moon in the Command Module Columbia, and then both copies were transferred from the Command Module into the Lunar Module Eagle and then carried down to the Lunar surface, were both Armstrong and Aldrin made notations on both copies. One of these two copies was supposed to have been jettisoned and left on the Lunar surface (and indeed the Apollo 11 Stowage List lists a quantity of 2 being loaded into the CSM for launch, a quantity of 2 being transferred to the LM from the CSM for the descent, and then a quantity of only one be transferred back into the CSM from the LM for the return ) but Aldrin decided to keep both copies. (The complete copy that was to be jettisoned was sold in these rooms in 2022, as lot 16 in the "Buzz Aldrin: American Icon" sale for $567,000)

BUZZ ALDRIN'S provenance letter reads, in full:

"Enclosed with this letter is a sheet numbered ACT-58 and ACT-59 from the Apollo 11 LM Activation Checklist. The entire checklist was carried to the Moon on the flight of Apollo 11 during July 16 to 24, 1969. Then the checklist, including this sheet, was taken to the surface of the Moon in Lunar Module Eagle during the first lunar landing on July 20, 1969.

Sides ACT-58 and ACT-59 refer to the end of the completion of Rendezvous Radar (RR) on board the Lunar Module Eagle and the beginning of the Abort Guidance System (AGS) calibration. Both procedures were absolutely crucial to complete before Neil and I could safely undock Eagle from Columbia and continue to the lunar surface. The Rendezvous Radar was an essential tool for Neil and I to reunite with Mike in Columbia to return home, so it was important to test that it was in working order before the spacecraft separated.

ACT-58 also involves the calibration of the Abort Guidance System (AGS). The AGS was our system backup in case the Primary Guidance and Navigation System (PGNS) failed. The only use of the AGS was to get Eagle to a safe orbit if PGNS failed. One of my main tasks as LMP was to operate the AGS, comparing the AGS information of our trajectory with the information given by the PGNS. Mike maneuvered to the angles written on the page, and we stayed steady as a rock for the time it took the AGS to calibrate, doing no other tasks or checks to keep from jolting the spacecraft. The ICDU refers to the Inertial Coupling Data Unit. These were electronic packages that took signals from the resolvers on the LM gimbals in the Inertial Measurement Unit (IMU) and translated them into angles that the computer could read. 

The AGS accelerometers also have to be calibrated during this process. The AGS was inherently prone to drift. Any reading of acceleration by the accelerometers when the LM was in freefall could be used to indicate their bias and therefore could be compensated for as we proceeded. Side ACT-59 refers to the calculation of this bias.

This LM Systems Activation Checklist sheet from Apollo 11 is from one of the few documents used both in lunar orbit and on the Sea of Tranquility. It is a rare example of an astronaut flight-certified object used on the first landing on the Moon."

REFERENCES:

NASA. Apollo 11 Stowage List. Mission AS 506 CM 107/LM-5. Houston, Texas: Manned Spacecraft Center, July 15, 1969, pp. 3, 51, 57, 74, and 83