How the Eagle Landed: Grumman Construction Log, and a message to space (Apollo 11)

On the anniversary of Apollo 11, Steve Jurvetson posted an amazing, never-before-seen series of space artifacts. He writes:

On July 20, 1969, Eagle landed on the moon. These are the handwritten notes from the Grumman engineers as they pushed to complete Lunar Module LM-5 in 1968. On the last page, they learn than this particular Lunar Module would be the one to bring the first humans to the moon.

The Grumman Engineering Log served not only as an engineering notebook but also as an intercom between the day and night shift – separate teams that needed to push the ball forward from where the other left off. So we are offered a rare peek into the concerns, uncertainties and conversations that might have otherwise been quietly undocumented.

This log has informed the writing of Pellegrino’s book Chariots for Apollo, but only a few scholars have had access to these pages to date. Heritage reported that this original document is the only one in existence, with no copy on file anywhere. So I thought it would be good to make a color scan of the entire book, and make it available to all. So, here is the PDF file (8MB).

My hope is that we can collectively decode some of its mysteries, or better yet, find some of the engineers to see if it jogs their memories. There is a list of all of the engineers on p.2. We only have first initial and last names. So any insights to the full names or their whereabouts would be appreciated.

I am also hoping that space historians who come across interesting passages can share what they know in the comments below (with reference to date or page number). Are any of the part numbers significant, especially those swapped between the Apollo 9,11,12 and 13 Lunar Modules? I will also add a glossary of acronyms below as we decode them. Also, if anyone can OCR the hybrid handwriting, please do. Our attempts with free OCR tools have failed so far.

Here's the Flickr page, with lots more details, and lots more links.

At left, Steve with a prototype build of the first flagpole assembly on the moon.

"I brought it to Buzz Aldrin, and his eyes went wide," he says. "But from what I learned, there probably is no Apollo 11 flag on the moon today."

How exciting. Happy space-a-versary, everyone!

And here's another amazing artifact photographed by Steve, below: a silicon disc, FROM PLANET EARTH.

On the Flickr page for this photo, Steve writes:

On this day in 1969, Apollo 11 took flight to the moon. In the days that preceded the launch, the U.S. scrambled to pull together the messages from Earth that would be left behind on the moon. This is the Apollo Goodwill Disc, and it was engineered to last long after the U.S. flag was destroyed."

This silicon disc contains etched letters (scanned and reduced 200x) from the leaders of the world’s nations. This is one of the discs produced by Sprague and retained by a Sprague manager; a second resides in the Smithsonian, and a third rests on the Moon's Sea of Tranquility, deposited there by Buzz Aldrin.

(Does anyone know if other builds remain intact? A Sprague press release says that of the handful of discs made, one was given to President Nixon and one to President Johnson).

It is a tricky subject matter for photography. I wanted to capture the angle-dependendent iridescence of the semiconductor thin films. The overhead light source reflects off the leather seat cushion, revealing the shift from green to purple that occurs at oblique angles.

This comes from the early days of the semiconductor industry, when Apollo consumed 50% of global production, and wafers were just 2” wide (the ultimate disc was cropped around the 1.5” metallized ring and placed in a aluminum case).


  1. Three-ring binders… slide rules… duct tape… The world of Apollo was a nation on the cutting edge of technology, pushing every part of it, using what seems to us today to be antiquated techniques. Imagine that the computers that sent the Saturn V into orbit, the CSM and LM to the Moon, and assisted Neil and Buzz in their descent to the lunar surface were not constructed from silicon chips, but wires looped through copper rings, that had to be woven — by hand! — in a certain fashion or they would not work properly. When anyone wants to point to something America can truly be proud of, it should be the Apollo program, because it showed how science, industry, and the coming together of hundreds of thousands of Americans could accomplish one of the truly amazing feats of the 20th Century.

        1.  The Germans they were copying initially from were the ones building the new rocket. The Saturn V is waaay more advanced than any V-2 of the Germans.

      1. There were hundreds of thousands of hard engineering issues to resolve in order to land a man on the moon and bring him safely home. Your implied dismissal of this mammoth undertaking with a glib comment reveals a profound ignorance.

      2. Really?  The British had a rocket capable of going to the moon in 1969?  I did not know that.  You guys should have spoken up.

    1. The technique is still relevant today. Fermilab uses software that around the lab is referred to as the “logbook”. It’s basically a web tool to enter notes, images, and random thoughts as the experiment runs. Shifters use it to pass knowledge to the next shift and make note of strange happenings so they can be investigated in detail later.

      Entries are never deleted.. it’s basically a giant rolling notebook that goes back ~20 years. A physicist can look up an entry by date and gain some insight on the status of the detector on that day. 

      There are also entire shelves filled with three ring binders that were populated prior to the existence of the software.

    2.  re: “but wires looped through copper rings, that had to be woven — by hand!”

      Rope memory! I thought I was the only one who knew that little known space fact.

    3.  The Apollo 15 lunar module landed in a valley surrounded by mountains. The flight control system had a terrain model of the landing site which consisted of five vectors, each vector representing one point in space. These days you would probably model every single rock.

    4. A couple of inaccuracies there. The computer did in fact use silicon chips for the logic. It was the woven memory that was constructed by hand but the rings were made of ferrite. Copper is not magnetic, it wouldn’t have transferred the pulse. It is quite astounding how programs were recorded in patterns of these thousands of beads. Imagine if the programmers make a mistake, the poor ladies would have have to do it again.

      1. Core memory, while persistent in the absence of power, was RAM as we know it: no need to re-weave to fix mistakes.

  2. The HBO miniseries From The Earth to the Moon had an entire episode (Episode #5) about the design and development of the Lunar Lander. It’s a fantastic display of teamwork, design, innovation and working around tough constraints. Highly recommended for engineering and design students or anyone looking for inspiration:

    1. That episode is probably the best illustration of the ‘design process’ ever made. They should screen it in design schools.

  3. OCRing would be a good crowd-sourcing job.  Get a bunch of people to volunteer to do one page or use the Amazon Mechanical Turk.

  4. pg 4 transcript

    Grumman Aircraft Engineering Corporation


    Page No. 73052
    Engineer A. Hecht
    Project LM-5
    Location Plt 5
    Time 8am/6pm day shift
    Title —–
    Date 6-5-68

    (1) Mod 14 to TPS 70010 prep was issued last night, deleting ECS Control Unit & all assoc. cables (because P/J 765 cannot be mated due to absence of ECS relay Box).

    (2) Generated dev. #8-11 to incorporate Mod 14 change into OCP (temporary).

    (3) Attended LM5 Mtg: Heard following statement: DO NOT USE Bag of OLD CB Guards delivered to vehicle yesterday. They may be TIGHT FIT.
    Delivery of NEW CB guards promised for 6/10 (Mon)

    (4) Waited for QC coverage to transfer stamps fr. 70010 Prep TPS to OCP from 0915 until 1430. No QC coverage available.
    Advised Pad Supervisor, Don Getnost(QC), D. De Martino, R. Valdez (QC), Meeting at Command post (incl. Al Beauregard), and Milt Cohen.
    Result: At 1430 still no QC, no promise except “We’ll try for tonight”. Pad supvsr will call X6111 if when QC becomes available. Returned to plt 39.


    (5) Checked 1730 w. pad supervisor for QC assignment. He suggested we call back after 1815 to get QC coverage (ask for Vinnie Mackel, pad supvsr).

    ok now someone please proofread this and do the next page, thanx!

      1.  Your formatting is preferable I think – also you can spell “Aircraft”, “absence”, “try” and “17:30” correctly, and I apparently can’t. Agree my “for” is more correctly “fr.” (meaning “from”).  And yay! I love that you realised that scribbled out thing said ‘if’ – that adds a LOT that I totally missed!

        You have “supervisor” in one place where I think the original says “supvsr”, and I think we’re both wrong: what I put as “pet 39” and you as “PH 39” should be “Plt 39” (platform 39?) and the location at the top of the page should be “Plt 5”. Yup, confirmed from page 5.

        In sum, I feel your transcription is considerably more faithful to the original to mine, but a wiki would really be the best place for this if we could get one.

        1. yeah I agree with you about a wiki. but I thought, ah why not, this might turn out to be an interesting thread project. we could race the flickr page :)

          your QC was implemented, thank you good sir

  5. Here’s an interesting tidbit from p.73064 on the Master Alarm:

    Vehicle powered-up, and back on line with TPS 35-923.
    TPS completed 1600. Conclusions –
    1. 35uF at P/J 148 pins C&D seemed just at the verge of preventing the master alarm when switching from “Off” to “Inv 1”.
    2. With 50 uF, the master alarm never came on, in 10 cycles of switching from “Off” to Inv 1″ and to “Off” again.
    3. With the 50 uF, the master alarm came on – as it should – when the AC bus was de-energized.

    It’s no wonder that the alarm would trigger randomly, if they were
    changing an electrolytic capacitor value by 30% to stop it happening. Electrolytic capacitors
    are known to have widely varying values, even the god ones that NASA

    The conclusion that I reach from this is that the design needed to be redone to use different methods of detecting problems, so it wouldn’t depend on component values being just ever so.

  6. Amid the technical entries there are notes from everyday life, like this one from 6/20/68 (page No 73066 – page 18 of the PDF). A Hecht wrote “Please note that my pay check was locked up and unavailable to me, forcing me to come in tomorrow during the day in order to get cash at a bank before closing (& before returning to work). It would be well if night shift personnel could have their checks brought to the ACE Station in the future, the avoid similar inconvenience.”

  7. I just found out this year that for Apollo 15, 16 and 17 the top hatch of the LM was opened and the Commander was basically standing  up with his head out “teenager in a limo style”  for the final descent. WOW. What a fan-freaking-tastic view that must have been.

    1. Commander was basically standing  up with his head out “teenager in a limo style”  for the final descent.

      No thats wrong. You can read more in the Apollo Lunar Surface Journal. In all, landings the commander had manual control of the vehicle at touchdown and viewed the lunar surface through the left front window. This notion may have come from Apollo 15 where the crew did a Stand Up EVA after landing. To do that they decompressed the LM and opened the top hatch. One of the crew climbed up and stuck their head out of the hatch. It was done to get panoramic photos of the landing site with a long lens, and to survey the landing site for the first main EVA with the rover.

        1. You may be thinking of proposed versions of the lander that were never built. Very interesting book by Robert Godwin called “The Lunar Exploration Scrapbook,” which had a ton of wild designs and concepts. It’s on Amazon if you’re interested: The Lunar Exploration Scrapbook : A Pictorial History of Lunar Vehicles

  8. Steve, this is great stuff!  Come by some time and I will show you some of the design and test data for the original Saturn V.  As far as I know it is the only copy in existence as I got it from the wife of an Apollo engineer that died and she didn’t want any of it.

Comments are closed.