Today my local paper, the Findlay COURIER, published an only slightly edited version of an article I wrote for them. The online version is available only to subscribers and the TOS prohibits me from posting a photograph of the text. At 500 kB max, that might be too grainy anyway.
The text is mine, anyway, so I thought I'd share it here:
APOLLO ACCELERATED MODERN ENGINEERING
As I pop a huge two-pound, six lens, wide angle eyepiece into my homemade 10" reflector to look at the beauty of the entire moon, I am humbled and awed by the extraordinary growth of engineering spawned directly by the Apollo Program of the 1960s.
Telescope optics, like that in my hand that deliver crisp, undistorted wide angle views seen comfortably even through eyeglasses were inspired by the optical designs of landing simulators developed in the 1960s and 1970s for the U.S. government. When Texas Instruments invented the first solid state calculator in 1966, more than 60% of integrated circuits, the precursors to modern computer chips, were being made for the Apollo Program. President Kennedy had given us the challenge to travel to the moon and to return safely, a challenge made more than four years prior to even the invention of the pocket calculator!
The Lunar Lander of the Apollo 11 mission had a 70 pound "microcomputer" on board to perform most of the landing maneuvers automatically for the first time ever. On board Buzz Aldrin punched numbers in "noun-verb" combinations into this computer to initiate programs and receive critical data on a single numeric display line.
When the computer was being overloaded during the critical minutes of powered landing, it displayed "1202" and "1201"error codes. This signalled that it had to prioritize its functions and could not presently calculate the variance in altitude from plan Buzz Aldrin was then requesting. Mission Control seamlessly offered to verbally provide that "Delta h" during descent by performing calculations from about a quarter of a million miles away. This was typical of the human-machine integration throughout this program.
Minutes before landing, the Apollo 11 lunar module was aproaching the surface of the moon at least 20 feet per second horizontally faster than planned and was overshooting the targeted landing site. After several incredibly precise rocket burns, this situation was a surprise to all involved. It was only later learned that in undocking from the command module some residual air not completely evacuated in the connecting tunnel had provided unexpected thrust between the command and lunar modules, like a cork popping from a bottle.
As the lander rotated towards vertical and Neil Armstrong saw the new "DLP" or Designated Landing Position, car-sized boulders littered the area. It may be hard for those today who are accustomed to such things as automobile back up cameras to even fathom the technology of 1969. Aldrin read calculated angles from the single line of the computer display while Armstrong sighted through corresponding calibrated lines on his triangular window to sight the anticipated touchdown location. Again and again he pushed forward until landing was acheived with only eighteen seconds of fuel remaining. That eighteen seconds was estimated back at mission control by a man with a stopwatch with tape marks on it who was taking into account Armstrong's variation at the throttle since the low fuel indicator had come on.
The mission had come within seconds of an abort command from one of hundreds of controllers who were of average age 26. In the uncharacteristic structure of Mission Control, authority was granted at the lowest possible levels for the best decision-making.
While previous space programs including the Gemini Mission had about 400 core employees, the Apollo Missions had grown to about 400,000 contributors, including contractors. President Kennedy's challenge to land on and return from the moon by the end of the decade had been responded to.
So much of the engineering of this program affects us to this day. Two of those contributors deserve special recognition in the opinion of this amateur astronomer and mechanical engineer.
Don Eyles, fresh out of college, wrote the code for that early computer used on the Lunar Module for the Massachusetts Institute of Technology Instrumentation Lab.
MIT got the first and only University contract with the Apollo program at a time that software engineering didn't even exist. Eyles had the brilliance to program in such a way that the computer could prioritize multiple tasks with its limited memory, even turning off the display to attend to critical functions.
Al Nagler, a native of the Bronx and an amateur astronomer to this day, was the optical engineer who created the landing simulator that Armstrong and Aldrin trained in for more than 2000 hours.
This simulator projected a combined image that appeared infinitely far away through the small triangular windows in the model of the lunar module. It was done with mirrors - six foot mirrors, and a series of optics ending with a three foot diameter lens. The image of the lunar landscape was actually recorded by a television camera in an adjacent room pointed at the "lunar" ceiling.
The star field they saw beyond or instead of the landscape was actually 1000 ball bearings of differing sizes on a hemisphere, illuminated by a hidden light. Al Nagler, in his characteristic attention to detail, even had some of these ball bearings gold plated to represent the redder stars.
Software engineering became a discipline because of the efforts of the very few, like Mr. Eyles on this project.
Computer hardware from the time quickly evolved into what we use today. Mr. Nagler dreamed big after such projects and has since founded Televue Optics, which makes the best eyepieces for astronomers to this day.
Many people think of the first moon landing as a huge cultural event. It certainly was, but I see the whole process leading up to it being a huge catalyst for almost all aspects of engineering today.
I'm glad I've been able to meet "Uncle Al" in person at several astronomy events and to thank him for his pioneering in eyepiece design and for his vision in providing the astronauts with "the right stuff".
-- J. T. SENGHAS is a mechanical engineer who lives in Bloomdale and is the Vice President of The Millstream Astronomy Club in Findlay
Edited by jtsenghas, 19 July 2019 - 06:31 PM.